Research Article Synthesis and Characterization of Highly ...downloads.hindawi.com/archive/2014/126103.pdf · of nanocomposites to the mixture of reducing agent and dye (.MNaBH 4and

Research ArticleSynthesis and Characterization of Highly Efficient NickelNanocatalysts and Their Use in Degradation of Organic Dyes

Nazar Hussain Kalwar1 Sirajuddin1 Razium Ali Soomro1 Syed Tufail Hussain Sherazi1

Keith Richard Hallam2 and Abdul Rauf Khaskheli13

1 National Centre of Excellence in Analytical Chemistry University of Sindh Jamshoro 76080 Pakistan2 Interface Analysis Centre School of Physics University of Bristol Bristol BS8 1TL UK3Department of Pharmacy Shaheed Mohtarma Benazir Bhutto Medical University Larkana 77150 Pakistan

Correspondence should be addressed to Razium Ali Soomro raziumsoomrogmailcom

Received 10 October 2013 Revised 4 January 2014 Accepted 9 January 2014 Published 27 February 2014

Academic Editor Sepperumal Murugesan

Copyright copy 2014 Nazar Hussain Kalwar et al This is an open access article distributed under the Creative Commons AttributionLicense which permits unrestricted use distribution and reproduction in any medium provided the original work is properlycited

The present study describes the synthesis of highly active and ordered structures of nickel nanocatalysts by a facile green andeconomically viable approachThe study reveals efficient catalytic activity for the degradation of a number of toxic organic dyes suchas eosin-B (EB) rose bengal (RB) eriochrome black-T (ECBT) and methylene blue (MB)The stable ordered nickel nanostructure(Ni NSs) arrays were prepared via a modified hydrazine reduction route with unique and controlled morphologies in a lyotropicliquid crystalline medium using a nonionic surfactant (Triton X-100) Characterization and optimization studies for the fabricatedNi NSs involving their surface binding interactions size and morphologies were carried out using UV-Vis spectroscopy Fouriertransform infrared (FTIR) spectroscopy X-ray diffraction (XRD) and scanning electron microscopy (SEM)

1 Introduction

The widespread interest in the synthesis of metal nanomate-rials has largely been driven by their potential applications invarious fields ranging from sensors and optical switches tocatalysis [1] Similarly the control over pollution especiallycontamination of the aquatic environment due to industrialeffluents has become an increasingly important and complexissue of present day research concern The existence ofindustrially important dyes in drinking water may pose aserious threat to human health Since there are both envi-ronmental and health concerns in this particular issue thereis a need to introduce efficient and inexpensive protocolsfor the treatment of waters and effluents [2] A variety ofmethodologies have been developed for investigation of envi-ronmental contaminants which exploit the reactivity of targetmolecules with suitable reagents alone or in the presence ofcatalysts ultimately resulting in degradation removal or safe

disposal of environmental and aquatic pollutants [3 4] Someof the water treatment methods include adsorption method[5 6] biological discoloration [7] and advanced oxidationprocesses such as the photo-fenton reaction [8] photo-catalytic degradation by UV irradiation [9] visible light [10]and microwave discharge lamps [11 12] are well regarded forthe removal or degradation of dyes from wastewaters

However each of these technologies exhibits their ownlimitations For example dyes cannot always be completelyeliminated by biological methods because most dyes arerecalcitrant molecules the pollutants are not degraded byadsorption but are just transferred from one phase to theother and advanced oxidation processes are limited due tohigh energy requirements and expensive operating costs [1314] The UV-induced degradation of industrially importantazo dyes such as methyl orange (MO) and methyl red(MR) has been carried out by employing different catalystsThe reduction for MO was 38 for nh-ZnO 89 for

Hindawi Publishing CorporationInternational Journal of MetalsVolume 2014 Article ID 126103 10 pageshttpdxdoiorg1011552014126103

2 International Journal of Metals

ZnO Aldrich and 95 for h-ZnO Further the percentagereduction for MR was 54 for nh-ZnO 93 for ZnOAldrich and 100 for h-ZnO all these were obtained after120 minutes [15] Degradation and decolorization of acidblack 26 dye have also been studied through a heterogeneouscatalytic approach It was established that in the presence ofTiO2particles alone acid black 26 (dye 0071mM H

2O2

0023mM) was degraded to a greater extent than TiO2

coated sackcloth fiber after 60min They observed thatit took 3 h to effectively decompose all dye molecules insolution using TiO

2-coated sackcloth fiber [16] In another

report Ag-HDx-g-PAM nanocomposite was used for thereduction of pollutants like aromatic nitro compounds andphenosafranine (PS+) dye It was seen that after the additionof nanocomposites to the mixture of reducing agent and dye(001MNaBH

4and 005mMPS+) the solution changed from

light pink to yellowish brown due to reduction of the dyeThey observed complete reduction of the dye in 30min afteraddition of 00065wt of Ag-HDx-g-PAM nanocomposite[17] The role of MnFe

2O4mesoporous composites in the

degradation of methyl orange (MO) dye was investigatedThe MO solution was completely degraded by MnFe

2O4

mesoporous composites after 420min using 20mg of thecatalyst [18]

In a previous study it has been reported that the catalyticreduction of dyes was carried out by using gelatin stabilizedgold nanoparticles (GNPs) where the entire reduction pro-cess was completed in 150 s at room temperature with only012mg GNPs [19] In another report it has been describedthat nanoscale nickel particles (Ni NPs) are highly efficientcatalysts for reduction of congo red (CR 20 120583M) dye fromaqueous medium where 100 reductiondegradation of dyewas observed in a very short time (50 s) by the additionof only 02mg Ni NPs in the presence of reducing agent(100mM NaBH4) [20] Hence the literature demonstratedthat nanostructured Ni catalysts are highly efficient andimportant alternative to the already available catalysts whilebeing able to be easily recovered for use through several cycleswithout loss of catalytic efficiency Further studies have beencarried out giving much attention to probing control overthe morphology and growth patterning of Ni NSs and theeffect of different parameters on catalytic efficiency in termsof reaction kinetics However the prime objective of thispresent study is to explore the synthesis of Ni NSs and theircatalytic activity for the degradation of environmentally toxicand hazardous organic dyes

2 Experimental

21 Materials Used during Synthesis of TX-100 Stabilized NiNSs The nickel (II) chloride hexahydrate (97) hydrazinemonohydrate (99) Triton X-100 (100 the stabilizingagent) pellets of sodium hydroxide (99) hydrochloric acid(37) and sodium borohydride (98) were all purchasedfrom E Merck Due to possible oxidation of reagentsfresh solutions of chosen concentrations were prepared indeionized water for each experiment All these reagents

were analytical grade and were used without additionalpurification

22 Instruments Used during Characterization of TX-100 Sta-bilized Ni NSs The optimization studies of various param-eters were monitored by recording UV-Vis spectra on aShimadzu UV-160 digital spectrophotometer (Kyoto Japan)with a 1 cm quartz cuvette A Nicolet 5700 FT-IR spec-trophotometer was used to record FTIR spectra A Jeol JSM6380A SEM was used to image the nanostructures A BrukerD8 ADVANCE diffractometer was used to record X-raydiffraction patterns from 20∘ to 80∘ using CuK120572 radiation

23 Synthesis Procedure of TX-100 StabilizedNiNSs A typicalexperiment was performed by mixing NiCl

2sdot6H2O (05mL

0033M) NaOH (03mL 01M) N2H4sdotH2O (10mL 02M)

and Triton X-100 (05mL 05M) at room temperature thesolution was then diluted to 10mL with deionized water Asthe reaction proceeded after a few minutes a light blue colorappeared as sufficient quantities of reducing agentwere addedthat gradually became deeper with increase in the quantity ofreducing agent

24 Catalytic Test of TX-100 Stabilized Ni NSs Investigationof the catalytic efficiency of newly synthesized Ni NSs fordegradation of a number of organic dyes has been carried outfresh samples of Ni NSs were prepared and deposited on glasscover slips for each experiment For efficient adhesion of NiNSs onto glass surfaces the deposited catalyst was thermallytreated on the cleaned surface of an electric hotplate at 150∘Cfor 10min The supported catalyst of suitable quantity wasplaced in a quartz cell and then inside a cuvette in oppositionto the light beam to monitor in situ the course of reaction byUV-Vis spectroscopy

A typical catalytic test of Ni NSs for degradation oforganic dyes was carried out under normal laboratory con-ditions Organic dyes such as eosin-B (EB) rose bengal(RB) eriochrome black-T (ECBT) and methylene blue (MB)were selected as target compounds to check the efficiency ofthe catalyst All experiments were performed in an aqueousmedium using 20120583M concentration of the respective dyes001M NaBH

4(reducing agent) and 01mg quantity of Ni

NSs (catalyst) A similar experiment was also performed fora mixture of all four dyes with 20120583M concentration of eachdye 001M NaBH

4(reducing agent) and 01mg quantity of

Ni NSs (catalyst) UV-Vis spectra were recorded every 10 sduring the course of reaction

We observed that in the absence of Ni NSs there wasno reductiondegradation of MB and RB dyes and EB andECBT were degraded only to a small extent whereas all dyeswere completely degraded in a very short time when treatedwith NaBH

4in the presence of 01mg Ni NSs complete

degradation of RB dye was observed within 20 s EB degradedin 30 s other dyes such as ECBT and MB were degradedwithin 40 s and the mixture of all four dyes was degraded in60 s

The Ni NSs were reused several times to confirm theretained catalytic efficiency The experiments were carried

International Journal of Metals 3

out to observe complete reductiondegradation of 20120583Mconcentrations of each dye in very short times (ie 20ndash60 s)

3 Results and Discussion

Formations of mixed nickel nanostructures (Ni NSs) sheetsfoils cubes and spheres with controllable morphologies havebeen described using a nonionic surfactant (Triton X-100)as a stabilizing agent under normal laboratory conditions inan aqueous solution For nanosized Ni NSs prepared usinghydrazine as the reducing agent themechanism for reductionis similar to that of our previous report and further referencestherein [21]

Consider

2Ni2+ + N2H4+ 4OHminus 997888rarr 2Ni +N

2uarr + 4H

2O (1)

31 Characterization of TX-100 Stabilized Ni NSs

311 UV-Vis Spectroscopy of TX-100 Stabilized Ni NSs Thenanometer size regime of newly synthesized nickel structureswas spectrophotometrically monitored these exhibited acharacteristic absorption profile in the range 350ndash400 nm(Figure 1) in close agreement to previously reported work[21]

Depending on the nature of samplesolution Ni particlesgenerated an absorption edge in the UV-Vis spectral range374ndash422 nm corresponding to the surface plasmon reso-nance (SPR) band of nanosized Ni particles after reductiongenerated by Ni (II) ions [22 23] Optimization studies forreducing agent concentration surfactant concentration andpH were carried out to check their effect on the peak shapeto further help in the estimation of structuremorphologyand size of nanoscale metal particles The photoevolution ofNi particles suggests that the change in nature and profileof UV-Vis spectra is due to complete reduction of Ni (II)ions in surfactant solutions The stability of Ni NPs wasstudied by aging solutions for many days It was observedthat surfactant molecules impart stability to the colloidaldispersionsclusters and also control morphology and size ofthe crowded nanoparticlesstructures [17 24]

The appearance of the faint blue color of the samplesolution and progression of the spectral profile resulted ina blue shift in 120582max from 391 nm to 366 nm with gradualincrease in absorbance by increasing the reducing agentThis was observed by changing the concentration of thereducing agent gradually as 02mL 04mL 06mL 08mLand 10mL of 02M hydrazine hydrate solution (N

2H4sdotH2O)

the correspondingUV-Vis spectra recorded for these samplesare presented in Figure 1(a) The development of the spectralprofile of TX-100 stabilized Ni NSs recorded after increase inconcentration of surfactant (stabilizingcapping) is absolutelydifferent in the present scenario from that of previousresults as the present study reveals that gradual increasesin concentration of stabilizingcapping agent generated a redshift in 120582max from 382 nm to 393 nm as shown in Figure 1(b)due to the creation of a larger micelle network formed bysurfactant molecules in the adopted wet chemical method

These UV-Vis spectral results were obtained by stepwiseincrease in concentration as 025mL 05mL 075mL and10mL of Triton X-100 (05M) solutions Figure 1(b) Theformation of larger micelle networks at high concentrationsmight be due to the presence of attractive intermicellar inter-actionswhich lead to enhancedmicellar growth and potentialagglomeration of micelles to larger spherical particles [25]

In principle for practical increases in surfactant concen-trations the red shift in 120582max (from 382 nm to 393 nm) is lin-ear with concentration and can be credited to an increase inmicellar size The study shows that UV-Vis spectra recordedat different pH values of the samplessolutions exhibiteddistinctive absorption maxima as shown in Figure 1(c) thatexplore the formation of nanoscale nickel structures withdifferent size and shapes

The selection of samples at different pHwas carried out tosee the effect of pH on size and shapes of Ni NSs the lowestobserved 120582max value was from pH 94 Moreover due to theformation of highly aggregated nanoparticles (precipitates)there was no well resolved peak resulting from the solutionabove pH 94 hence it is estimated that the optimal pH was94 It is also understood that the surfactant molecules coverthe surface of nanoscale nickel particles giving them stablesize and shape shown schematically in Figure 2

Further studieswere carried out using FTIR spectroscopySEM and XRD for structural elucidation and rationalizationof interaction of surfactant molecules with particles to con-firm size and morphologies of the TX-100 stabilized Ni NSs

312 Fourier Transform Infrared (FTIR) Spectroscopy FTIRspectra were recorded to examine the interaction of TX-100 molecules with the surfaces of Ni NSs as presentedin Figure 3 which shows that extended complexity andfunctionality of the nanoscale systems are predictable fromefficient linkages employed by the OH group of TX-100molecules and Ni particles obtained in lyotropic liquidcrystalline medium

This study showed that a very strong absorption band at2870 cmminus1 in connection with a weak signal at 3480 cmminus1appeared in the FTIR spectra of absolute TX-100 (stan-dardpure) due to the presence of free OH groups in thesurfactant molecules whereas TX-100 derived Ni nanostruc-tures with nanosheet and nanosphere morphologies initiatedthe appearance of a weak but broad signal at 3260 cmminus1 at theoptimized pHof 94 Basic pH resulted in a band at 3260 cmminus1due to high concentrations of OH moieties in the productsThe additional signals in the FTIR spectra of the Ni NSsobtained at pH 73 and pH 42 (as shown in Figure 3) were dueto interactions of zwitterionic moieties with particle surfacesat nearly neutral pH while those obtained from acidic pHwere expected to be due to strong linkages imparted fromamino groups with particle surfaces

313 Scanning Electron Microscopy (SEM) of TX-100 Stabi-lized Ni NSs Fabrication of nanoscalematerials with orderedand controlled structures has been given intensive attentiondue to their fascinating properties because the performance


300 350 400 450 500000

005

010

015

020Ab

s (au

)

Wavelength (nm)02mL04mL06mL

08mL10mL

(a)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)

Wavelength (nm)

025mL05mL

075mL10mL

(b)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)

Wavelength (nm)pH 94pH 8pH 4

(c)

Figure 1 UV-Vis spectra recorded for (a) optimization of reducing agent (hydrazine monohydrate 02M) resulting in a blue shift in 120582maxfrom 391 nm to 366 nm with increase in absorbance at various concentrations (b) optimization of TX-100 (05M) at various concentrationsresulting in a red shift in 120582max from 382 nm to 393 nm with increase in absorbance and (c) (selected spectra) optimization of pH study wherewe observed a blue shift in 120582max from 391 nm to 357 nm with increase in absorbance Further detail is given in the experimental section

of such materials is mainly dependent on size and mor-phology [26] The present study describes the synthesisof Ni NSs with controlled morphologies via a modifiedhydrazine reduction route using three typical pH valuesSEM images show that Ni NSs samples prepared at pH 94consisted of mixed structures of hexagonal nanosheets withsmooth surfaces and well-dispersed spherical nanoparticleswith rough surfaces but uniform in size To determinethe dynamics of surfactant stabilized nanoparticle size and

growth patterning at different pH values in the lyotropicliquid crystalline medium SEM images were recordedsubsequent data are shown in Figure 4 and Figure S-1 toFigure S-2 of the supplementary data available online athttpdxdoiorg1011552014126103

These data demonstrate that mixed structures of finenickel nanosheets (Ni NSs) and rough-surfaced nickelnanoparticles (Ni NPs) are clearly seen at pH 94 Themethod is introduced for synthesis of mixed nanostructures


HO O OHO

OO

HOO

O

HO

OO

HO

OO

HOO

O

HOOO

HOOO

HO

OO

HO

OO

HO

OO

HOO

O

Figure 2 Schematic representation of the TX-100 stabilized Ni NSs

4000 3500 3000 2500 2000 1500 100000

05

10

15

20

(d)

(b)

(c)

Abs

(a)

Wavenumber (cmminus1)

Figure 3 FTIR spectra of (a) standard TX-100 solution recorded onATR (b) TX-100 stabilized Ni NSs at pH 94 (c) TX-100 stabilizedNi NSs at pH 73 and (d) TX-100 stabilized Ni NSs at pH 42

containing highly ordered assemblies of 2D nanosheetsfoilswith smooth surfaces and thicknesses in the range of 24ndash240 nm while the mean thickness is 72 nm these nanosheetsare found to be 09ndash70120583m across averaging 31 120583m andthe size of spherical nickel nanoparticles ranged from 8 to300 nm with the observed average size of 45 nm in pH 94

These Ni NSs were used as heterogeneous catalysts forthe reductiondegradation of a number of organic dyes andfound to be highly active catalysts recoverable even afterseveral uses Such nanostructures may also be employedfor the development of innovative devices promising uniqueproperties in the fields of microelectronics and sensors

314 X-Ray Diffraction (XRD) Study of TX-100 Stabilized NiNSs The phase compositions of crystal structures of theseproducts were analyzed by X-ray diffraction Figure 5 showsthe XRD pattern of powdered Ni NSs which corresponds tothe formation of nanosheetsfoils

For the Ni NSs obtained by the modified hydrazinereduction route and separation by solvent evaporation atnormal temperature (noncentrifuged sample) a Ni(OH)

2

layer on the nanoparticle was predictable from the XRDresults of sample 1 (Figure 5) The XRD peaks (at 2120579 values of2201∘ 3072∘ and 3311∘) corresponding to the Miller indices(001) (100) and (101) respectively are consistent with thosereported elsewhere and attributed to formation of Ni(OH)

2

[27 28]The nanosized nickel showed only two characteristicpeaks of pure face centered cubic (fcc) nickel (at 2120579 valuesof 4489∘ and 5344∘) assigned to Miller indices (111) and(200) as depicted in Figure 4 Similar results have also beenobserved previously in the literature [29]

Further it can be seen from the XRD results that alldiffraction peaks of sample 2 collected by separating thenanosized particles from the aqueous medium by ultrahighcentrifugation (ie 22000 rpm) resulted from the formationof purely fcc phase nickel structures illustrating the existence


(a) (b)

(c) (d)

Figure 4 SEM images of TX-100 stabilized Ni NSs obtained at pH 94

20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs

Figure 5 XRD patterns of TX-100 stabilized Ni NSs obtainedby modified hydrazine reduction route sample (1) noncentrifugedproducts and sample (2) centrifuged products of the as-preparednanosized nickel structures

of onlymetallic nickel particles [30]Weobtainedmixed crys-tal structures with typical diffraction patterns indicating theformation of fcc phase Ni NPs for Ni-based nanosheetsfoils

similar to those proposed in the literature [31] and confirmedby surface morphology SEM images

4 Application of TX-100 Stabilized Ni NSs

41 ReductionDegradation of Dyes Further experimentswere performed for dye degradationreduction with NaBH

4

in both the presence and absence of nanoscale nickel cata-lysts To investigate the catalytic activity of Ni NSs the ratesof degradation for several organic dyes such as rose bengal(RB) eosin-b (EB) eriochrome black-t (ECBT) methyleneblue (MB) and mixture of all four dyes were measuredusing UV-Vis irradiation The results obtained from theseinvestigations are presented in Figures 6(a)ndash6(e) and thecorresponding initial results for an un-catalyzed reactions toaccess the capability of reducing agent along with dyes in asimilar sample environment are provided as supporting dataFigures S3(a)ndashS3(e)

Dyes were chosen because they produce different colorshades in degraded and undegraded formsThe study showedthat newly fabricatedNiNSswere excellent catalysts Progressof the degradation of each dye was followed by the decreasein absorbance at their respective 120582max values in the UV-Visspectral range similar studies have been reported previouslyfor the reduction of an organic dye [32] That study showedreduction of acridine orange in 30minusing Pdnanoparticlesvia a homogeneous catalytic approach [32] In contrastNi NSs were used as catalysts following a heterogeneous


450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)

Figure 6 UV-Vis spectral analysis for catalytic reductiondegradation of a variety of dyes (a) 002mM RB (b) 002mM EB (c) 002mMMB (d) 002mM ECBT and (e) mixture of all four dyes carried out in 40mL of deionized water with 001mM NaBH

4in the presence of a

fixed amount of TX-100 stabilized Ni NSs (02mg) obtained at pH 94


Table 1 Catalytic degradation of organic dyes using Ni NPs as catalyst

Dye Substrate Time (s) Rate (1198961) Yield TON TOF

RB Ni NPs 40 00549 96122 3733493 159EB Ni NPs 40 01143 98045 566989 331ECBT Ni NPs 40 00814 95558 641747 236MB Ni NPs 40 00382 97331 432865 111Mixture Ni NPs 60 00139 95504 mdash 403

0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles

Catalytic effiency of Ni NPs

RBEBMB

ECBTMixture

Figure 7 Histogram showing the recovery of TX-100 stabilized NiNSsNPs immobilized on a glass surface (the same catalysts) andused for five cycles that still resulted in fast reduction of the dyes(ie RB EB MB ECBT and mixture) with high yields

catalytic approach which is much more safe cost effectiveand advantageous allowing their use several times with goodefficiency The present study revealed that RB and EB dyeswere not reduced without the use of catalyst whereas MBand ECBT showed little decrease in absorbance with timeHowever in the presence of catalysts very fast degradation(ie 20ndash60 s) of all used dyes was observed

The efficiency of TX-100 stabilized Ni NSsNPs for reduc-tiondegradation of the dyes (ie RB EBMB andECBT)wasmonitored Figure 7 demonstrates how Ni NPs immobilizedon a glass surface (the same catalysts) and used for five cyclesstill resulted in fast reduction of the dyes (ie RB EBMB andECBT) with high yields reaction progress was monitored byUV-Vis spectroscopy

In addition it was also observed that newly fabricated TX-100 stabilized Ni NSs catalyzed dye reduction to nearly 100in the presence of NaBH

4in a very short time that is 20ndash

60 s furthermore the same catalysts could be recovered andreused several times

42 Catalyst Efficiency The catalyst efficiency for degrada-tion of organic dyes was calculated by employing the equa-tions for measuring extent of degradation turnover num-ber (TON) and mean turnover frequency (TOF) [33 34]

Thedye degradation percentage ratiowas calculated using thefollowing formula

Degradation () = [Abs0minus Abs

119905

Abs0

] times 100 (2)

(Abs0) is the initial absorbance of dye and (Abs

119905) is the

absorbance of dye on time 119905 The turnover number (TON)describing the ratio ofmoles of product obtained to themolesof catalyst used was calculated using the following formula

TON = (moles dye convertedmole of catalyst

) times 100 (3)

The cumulative TON for dyes at given times (ie formaximum degradation) to estimate the efficiency of catalystsis presented in Table 1

The mean turnover frequency (TOF) was also calculatedthat is the rate of change of TON for a reaction in any givenrecycling sequence (reflecting reaction rate for a fixed catalystloading) and was determined as the ratio of cumulativeTONtime from formula (4) the results obtained are alsogiven in Table 1

Consider

TOF =minus1198961(119904minus1) times [Analyte]

119905=0(119872)

[Ni NPs] (119872) (4)

From the above illustrations and the calculated values forTONandTOF it can be seen thatNiNPs possess highly activesurfaces to degrade large number of molecules of each dyeper unit amount of the catalyst in a very short time TheseNi NPs once immobilized onto the glass surface can be usedmany times to get good yields Hence it is observed thatthe Ni NSs synthesized by a simple and inexpensive protocolshowed good catalytic efficiency for the degradation of bothindividual and mixed organic dyes and thus applicability forthe removal of pollutants from water systems

5 Conclusions

The new simple and cost effective method is introduced forsynthesis of mixed nanoscale nickel structures containinghighly ordered assemblies of 2D nanosheets with absolutelysmooth surfaces and sheet thicknesses in the range of 24ndash240 nm (average thickness is 72 nm) these nanosheets arefound to be 09ndash70120583m across averaging 31 120583m and the sizeof spherical nickel nanoparticles is in the range of 8ndash300 nmwith the observed average size being 45 nm The extended


complexity and functionality of the nanoscale systems arepredictable fromefficient linkages employed by theOHgroupof TX-100 molecules and Ni particles in a lyotropic liquidcrystalline medium These NSs were used for the reductionof organic dyes and found to be highly active and efficientcatalysts

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

The authors acknowledge the Higher Education Commis-sion Islamabad Pakistan for funding and the NationalCentre of Excellence in Analytical Chemistry University ofSindh Jamhoro Pakistan and the Interface Analysis CentreSchool of Physics University of Bristol Bristol UnitedKingdom for provision of laboratory facilities during thisresearch Special thanks go to Dr Sean Davis and Dr LorenPicco of the University of Bristol Bristol United Kingdomfor their kind assistance with microscopy studies

References

[1] M A Breimer G Yevgeny S Sy and O A Sadik ldquoIncor-poration of metal nanoparticles in photopolymerized organicconducting polymers a mechanistic insightrdquo Nano Letters vol1 no 6 pp 305ndash308 2001

[2] H He S Yang K Yu Y Ju C Sun and L Wang ldquoMicrowaveinduced catalytic degradation of crystal violet in nano-nickeldioxide suspensionsrdquo Journal of Hazardous Materials vol 173no 1ndash3 pp 393ndash400 2010

[3] R Andreozzi V Caprio A Insola and R Marotta ldquoAdvancedOxidationProcesses (AOP) forwater purification and recoveryrdquoCatalysis Today vol 53 no 1 pp 51ndash59 1999

[4] J M Hermann ldquoHeterogeneous photocatalysis fundamentalsand applications to the removal of various types of aqueouspollutantsrdquo Catalysis Today vol 53 no 1 pp 115ndash129 1999

[5] MH Liao K YWu andDHChen ldquoFast adsorption of crystalviolet on polyacrylic acid-boundmagnetic nanoparticlesrdquo Sepa-ration Science and Technology vol 39 no 7 pp 1563ndash1575 2005

[6] O Gezici M Kucukosmanoglu and A Ayar ldquoThe adsorptionbehavior of crystal violet in functionalized sporopollenin-mediated column arrangementsrdquo Journal of Colloid and Inter-face Science vol 304 no 2 pp 307ndash316 2006

[7] J J Jones and J O Falkinham III ldquoDecolorization of malachitegreen and crystal violet by waterborne pathogenic mycobacte-riardquo Antimicrobial Agents and Chemotherapy vol 47 no 7 pp2323ndash2326 2003

[8] F A Alshamsi A S Albadwawi M M Alnuaimi M A Raufand S S Ashraf ldquoComparative efficiencies of the degradationof Crystal Violet using UVhydrogen peroxide and Fentonrsquosreagentrdquo Dyes and Pigments vol 74 no 2 pp 283ndash287 2007

[9] M Saquib and M Muneer ldquoTiO2-mediated photocatalytic

degradation of a triphenylmethane dye (gentian violet) inaqueous suspensionsrdquo Dyes and Pigments vol 56 no 1 pp 37ndash49 2003

[10] J Hong C Sun S-G Yang and Y-Z Liu ldquoPhotocatalyticdegradation of methylene blue in TiO

2aqueous suspensions

using microwave powered electrodeless discharge lampsrdquo Jour-nal of Hazardous Materials vol 133 no 1ndash3 pp 162ndash166 2006

[11] Z He C Sun S Yang Y Ding H He and Z Wang ldquoPhoto-catalytic degradation of rhodamine B by Bi

2WO6with electron

accepting agent under microwave irradiation mechanism andpathwayrdquo Journal of Hazardous Materials vol 162 no 2-3 pp1477ndash1486 2009

[12] Y M Ju S G Yang Y C Ding C Sun A Q Zhang and LH Wang ldquoMicrowave-assisted rapid photocatalytic degrada-tion of malachite green in TiO

2suspensions mechanism and

pathwaysrdquo Journal of Physical Chemistry A vol 11 no 44 pp11172ndash11177 2008

[13] C C Chen H J Liao C Y Cheng C Y Yen and YC Chung ldquoBiodegradation of crystal violet by Pseudomonasputidardquo Biotechnology Letters vol 29 no 3 pp 391ndash396 2007

[14] K Banerjee P N Cheremisinoff and S L Cheng ldquoSorptionof organic contaminants by fly ash in a single solute systemrdquoEnvironmental Science amp Technology vol 29 no 9 pp 2243ndash2251 1995

[15] RComparelli E FanizzaM L Curri PDCozzoli GMascoloand A Agostiano ldquoUV-induced photocatalytic degradation ofazo dyes by organic-capped ZnO nanocrystals immobilizedonto substratesrdquo Applied Catalysis B vol 60 no 1-2 pp 1ndash112005

[16] M Vaez A Z Moghaddam N M Mahmoodi and S AlijanildquoDecolorization and degradation of acid dye with immobilizedtitania nanoparticlesrdquo Process Safety and Environmental Protec-tion vol 90 no 1 pp 56ndash64 2012

[17] P K Rastogi V Ganesan and S Krishnamoorthi ldquoMicrowaveassisted polymer stabilized synthesis of silver nanoparticles andits application in the degradation of environmental pollutantsrdquoMaterials Science and Engineering B vol 77 no 6 pp 456ndash4612012

[18] B Sahoo S K Sahu S Nayak D Dhara and P Pramanik ldquoFab-rication of magnetic mesoporous manganese ferrite nanocom-posites as efficient catalyst for degradation of dye pollutantsrdquoCatalysis Science amp Technology vol 2 no 7 pp 1367ndash1374 2012

[19] Z A Tagar Sirajuddin N Memon et al ldquoFacile synthesischaracterization and catalytic function of gelatin stabilized goldnanoparticlesrdquo Pakistan Journal of Analytical and Environmen-tal Chemistry vol 13 no 1 p 70 2012

[20] N H Kalwar Sirajuddin K R Hallam et al ldquoFabricationof small l-threonine capped nickel nanoparticles and theircatalytic applicationrdquo Applied Catalysis A vol 453 pp 54ndash592013

[21] N H Kalwar Sirajuddin S T H Sherazi et al ldquoSynthesis ofl-methionine stabilized nickel nanowires and their applicationfor catalytic oxidative transfer hydrogenation of isopropanolrdquoApplied Catalysis A vol 400 no 1-2 pp 215ndash220 2011

[22] K Nouneh M Oyama R Diaz M Abd-Lefdil I V Kitykand M Bousmina ldquoNanoscale synthesis and optical featuresof metallic nickel nanoparticles by wet chemical approachesrdquoJournal of Alloys and Compounds vol 509 no 19 pp 5882ndash5886 2011

[23] H Amekura Y Takeda and N Kishimoto ldquoCriteria for surfaceplasmon resonance energy of metal nanoparticles in silicaglassrdquo Nuclear Instruments and Methods in Physics Research Bvol 222 no 1-2 pp 96ndash104 2004

[24] D Liu S Ren H Wu Q Zhang and L Wen J ldquoMorphologycontrol in synthesis of nickel nanoparticles in the presence of


polyvinylpyrrolidone (PVPK30)rdquo Journal of Materials Sciencevol 43 no 6 pp 1974ndash1978 2008

[25] P S Denkova L van Lokeren I Verbruggen and R WillemldquoSelf-aggregation and supramolecular structure investigationsof triton X-100 and SDP2S by NOESY and diffusion orderedNMR spectroscopyrdquo Journal of Physical Chemistry B vol 112no 35 pp 10935ndash10941 2008

[26] L Qi ldquoColloidal chemical approaches to inorganic micro- andnanostructures with controlled morphologies and patternsrdquoCoordination Chemistry Reviews vol 254 no 9-10 pp 1054ndash1071 2010

[27] R Chen Q Wang Y Du W Xing and N Xu ldquoEffect ofinitial solution apparent pH on nano-sized nickel catalysts in p-nitrophenol hydrogenationrdquo Chemical Engineering Journal vol145 no 3 pp 371ndash376 2009

[28] F Tao M Guan Y Zhou L Zhang Z Xu and J ChenldquoFabrication of nickel hydroxide microtubes with micro- andnano-scale composite structure and improving electrochemicalperformancerdquoCrystal Growth and Design vol 8 no 7 pp 2157ndash2162 2008

[29] Y Du H Chen R Chen and N Xu ldquoSynthesis of p-aminophenol from p-nitrophenol over nano-sized nickel cata-lystsrdquo Applied Catalysis A vol 277 no 1-2 pp 259ndash264 2004

[30] L Bai F Yuan and Q Tang ldquoSynthesis of nickel nanoparticleswith uniform size via a modified hydrazine reduction routerdquoMaterials Letters vol 62 no 15 pp 2267ndash2270 2008

[31] B Zhang X Ye W Dai W Hou and Y Xie ldquoBiomolecule-assisted synthesis and electrochemical hydrogen storage ofporous spongelike Ni

3S2nanostructures grown directly on

nickel foilsrdquo Chemistry vol 12 no 8 pp 2337ndash2342 2006[32] S Nath S Praharaj S Panigrahi S Basu and T Pal ldquoPho-

tochemical evolution of palladium nanoparticles in Triton X-100 and its application as catalyst for degradation of acridineorangerdquo Current Science vol 92 no 6 pp 786ndash790 2007

[33] M C Rosu R C Suciu I Kasco S V Dreve E Indrea andT D Silipas ldquoA spectroscopic study of dyes decomposition byirradiated nanocrystalline TiO

2rdquo Journal of Physics Conference

Series vol 182 no 1 Article ID 012078 2009[34] Y Zhang and T Ren ldquoSilica supported ruthenium oxide

nanoparticulates as efficient catalysts for water oxidationrdquoChemical Communications vol 48 no 89 pp 11005ndash11007 2012

Submit your manuscripts athttpwwwhindawicom

ScientificaHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

CorrosionInternational Journal of

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Polymer ScienceInternational Journal of



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CompositesJournal of

NanoparticlesJournal of



International Journal of

Biomaterials


NanoscienceJournal of

TextilesHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Journal of

NanotechnologyHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Journal of

CrystallographyJournal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014


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Advances in

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Smart Materials Research



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MaterialsJournal of


Nano

materials


Journal ofNanomaterials


ZnO Aldrich and 95 for h-ZnO Further the percentagereduction for MR was 54 for nh-ZnO 93 for ZnOAldrich and 100 for h-ZnO all these were obtained after120 minutes [15] Degradation and decolorization of acidblack 26 dye have also been studied through a heterogeneouscatalytic approach It was established that in the presence ofTiO2particles alone acid black 26 (dye 0071mM H

2O2

0023mM) was degraded to a greater extent than TiO2

coated sackcloth fiber after 60min They observed thatit took 3 h to effectively decompose all dye molecules insolution using TiO

2-coated sackcloth fiber [16] In another

report Ag-HDx-g-PAM nanocomposite was used for thereduction of pollutants like aromatic nitro compounds andphenosafranine (PS+) dye It was seen that after the additionof nanocomposites to the mixture of reducing agent and dye(001MNaBH

4and 005mMPS+) the solution changed from

light pink to yellowish brown due to reduction of the dyeThey observed complete reduction of the dye in 30min afteraddition of 00065wt of Ag-HDx-g-PAM nanocomposite[17] The role of MnFe

2O4mesoporous composites in the

degradation of methyl orange (MO) dye was investigatedThe MO solution was completely degraded by MnFe

2O4

mesoporous composites after 420min using 20mg of thecatalyst [18]

In a previous study it has been reported that the catalyticreduction of dyes was carried out by using gelatin stabilizedgold nanoparticles (GNPs) where the entire reduction pro-cess was completed in 150 s at room temperature with only012mg GNPs [19] In another report it has been describedthat nanoscale nickel particles (Ni NPs) are highly efficientcatalysts for reduction of congo red (CR 20 120583M) dye fromaqueous medium where 100 reductiondegradation of dyewas observed in a very short time (50 s) by the additionof only 02mg Ni NPs in the presence of reducing agent(100mM NaBH4) [20] Hence the literature demonstratedthat nanostructured Ni catalysts are highly efficient andimportant alternative to the already available catalysts whilebeing able to be easily recovered for use through several cycleswithout loss of catalytic efficiency Further studies have beencarried out giving much attention to probing control overthe morphology and growth patterning of Ni NSs and theeffect of different parameters on catalytic efficiency in termsof reaction kinetics However the prime objective of thispresent study is to explore the synthesis of Ni NSs and theircatalytic activity for the degradation of environmentally toxicand hazardous organic dyes

2 Experimental

21 Materials Used during Synthesis of TX-100 Stabilized NiNSs The nickel (II) chloride hexahydrate (97) hydrazinemonohydrate (99) Triton X-100 (100 the stabilizingagent) pellets of sodium hydroxide (99) hydrochloric acid(37) and sodium borohydride (98) were all purchasedfrom E Merck Due to possible oxidation of reagentsfresh solutions of chosen concentrations were prepared indeionized water for each experiment All these reagents

were analytical grade and were used without additionalpurification

22 Instruments Used during Characterization of TX-100 Sta-bilized Ni NSs The optimization studies of various param-eters were monitored by recording UV-Vis spectra on aShimadzu UV-160 digital spectrophotometer (Kyoto Japan)with a 1 cm quartz cuvette A Nicolet 5700 FT-IR spec-trophotometer was used to record FTIR spectra A Jeol JSM6380A SEM was used to image the nanostructures A BrukerD8 ADVANCE diffractometer was used to record X-raydiffraction patterns from 20∘ to 80∘ using CuK120572 radiation

23 Synthesis Procedure of TX-100 StabilizedNiNSs A typicalexperiment was performed by mixing NiCl

2sdot6H2O (05mL

0033M) NaOH (03mL 01M) N2H4sdotH2O (10mL 02M)

and Triton X-100 (05mL 05M) at room temperature thesolution was then diluted to 10mL with deionized water Asthe reaction proceeded after a few minutes a light blue colorappeared as sufficient quantities of reducing agentwere addedthat gradually became deeper with increase in the quantity ofreducing agent

24 Catalytic Test of TX-100 Stabilized Ni NSs Investigationof the catalytic efficiency of newly synthesized Ni NSs fordegradation of a number of organic dyes has been carried outfresh samples of Ni NSs were prepared and deposited on glasscover slips for each experiment For efficient adhesion of NiNSs onto glass surfaces the deposited catalyst was thermallytreated on the cleaned surface of an electric hotplate at 150∘Cfor 10min The supported catalyst of suitable quantity wasplaced in a quartz cell and then inside a cuvette in oppositionto the light beam to monitor in situ the course of reaction byUV-Vis spectroscopy

A typical catalytic test of Ni NSs for degradation oforganic dyes was carried out under normal laboratory con-ditions Organic dyes such as eosin-B (EB) rose bengal(RB) eriochrome black-T (ECBT) and methylene blue (MB)were selected as target compounds to check the efficiency ofthe catalyst All experiments were performed in an aqueousmedium using 20120583M concentration of the respective dyes001M NaBH

4(reducing agent) and 01mg quantity of Ni

NSs (catalyst) A similar experiment was also performed fora mixture of all four dyes with 20120583M concentration of eachdye 001M NaBH

4(reducing agent) and 01mg quantity of

Ni NSs (catalyst) UV-Vis spectra were recorded every 10 sduring the course of reaction

We observed that in the absence of Ni NSs there wasno reductiondegradation of MB and RB dyes and EB andECBT were degraded only to a small extent whereas all dyeswere completely degraded in a very short time when treatedwith NaBH

4in the presence of 01mg Ni NSs complete

degradation of RB dye was observed within 20 s EB degradedin 30 s other dyes such as ECBT and MB were degradedwithin 40 s and the mixture of all four dyes was degraded in60 s

The Ni NSs were reused several times to confirm theretained catalytic efficiency The experiments were carried





Consider


2uarr + 4H

2O (1)





2H4sdotH2O)










300 350 400 450 500000

005

010

015

020Ab

s (au

)


08mL10mL

(a)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)

Wavelength (nm)

025mL05mL

075mL10mL

(b)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)


(c)






HO O OHO

OO

HOO

O

HO

OO

HO

OO

HOO

O

HOOO

HOOO

HO

OO

HO

OO

HO

OO

HOO

O


4000 3500 3000 2500 2000 1500 100000

05

10

15

20

(d)

(b)

(c)

Abs

(a)







2


2




(a) (b)

(c) (d)


20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs






4




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials







Consider


2uarr + 4H

2O (1)





2H4sdotH2O)










300 350 400 450 500000

005

010

015

020Ab

s (au

)


08mL10mL

(a)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)

Wavelength (nm)

025mL05mL

075mL10mL

(b)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)


(c)






HO O OHO

OO

HOO

O

HO

OO

HO

OO

HOO

O

HOOO

HOOO

HO

OO

HO

OO

HO

OO

HOO

O


4000 3500 3000 2500 2000 1500 100000

05

10

15

20

(d)

(b)

(c)

Abs

(a)







2


2




(a) (b)

(c) (d)


20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs






4




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




300 350 400 450 500000

005

010

015

020Ab

s (au

)


08mL10mL

(a)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)

Wavelength (nm)

025mL05mL

075mL10mL

(b)

300 350 400 450 500000

002

004

006

008

010

Abs (

au)


(c)






HO O OHO

OO

HOO

O

HO

OO

HO

OO

HOO

O

HOOO

HOOO

HO

OO

HO

OO

HO

OO

HOO

O


4000 3500 3000 2500 2000 1500 100000

05

10

15

20

(d)

(b)

(c)

Abs

(a)







2


2




(a) (b)

(c) (d)


20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs






4




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




HO O OHO

OO

HOO

O

HO

OO

HO

OO

HOO

O

HOOO

HOOO

HO

OO

HO

OO

HO

OO

HOO

O


4000 3500 3000 2500 2000 1500 100000

05

10

15

20

(d)

(b)

(c)

Abs

(a)







2


2




(a) (b)

(c) (d)


20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs






4




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




(a) (b)

(c) (d)


20 30 40 50 60 70 80

S-2

Inte

nsity

(au

)

S-1

2120579 (degrees)

lowast

lowast

Ni(OH)2lowastNi NPs






4




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials




450 500 550 600 65000

05

10

15

Abs

Wavelength (nm)

Fresh

Rose B

10 s20 s

30 s40 s

(a)

450 500 550 60000

05

10

15

Abs

Wavelength (nm)

Eosin B

Fresh10 s20 s

30 s40 s

(b)

550 600 650 700 750000

075

150

225

300

Abs

Wavelength (nm)

M Blue

Fresh10 s20 s

30 s40 s

(c)

300 400 500 600 700 80000

05

10

15

20

Abs

Wavelength (nm)

ECBT

Fresh10 s20 s

30 s40 s

(d)

300 400 500 600 700 80000

05

10

15

20

25 Mixture

Abs

Wavelength (nm)

Fresh10 s20 s30 s

40 s50 s60 s

(e)








0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials







0

20

40

60

80

100

1 2 3 4 5

Con

vers

ion

()

Number of cycles


RBEBMB

ECBTMixture










119905

Abs0

] times 100 (2)


119905) is the



) times 100 (3)



Consider


119905=0(119872)

[Ni NPs] (119872) (4)


5 Conclusions






Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials







Acknowledgments


References















2WO6with electron








































CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials


























CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials










CeramicsJournal of







Biomaterials




Journal of


Journal of





CoatingsJournal of

Advances in








MaterialsJournal of


Nano

materials



Documents

Research Article Synthesis and Characterization of Highly ...downloads.hindawi.com/archive/2014/126103.pdf · of nanocomposites to the mixture of reducing agent and dye (.MNaBH 4and