Printing Silver Nanogrids on Glass: A Hands-on Investigation of Transparent Conductive Electrodes

Silver Nanogrid/Nanowire Importance

https://www.youtube.com/watch?v=UvzDBaXo2z8

The next generation of optoelectronic devices requires transparent conductive electrodes to be lightweight, flexible, cheap, and compatible with large scale manufacturing methods.

Kumar, A,. Zhou, C.; The Race to Replace Tin-Doped Indium Oxide: Which Material Will Win? ACS Nano, 4, 11-14.

Silver Nanowire Synthesis

Korte, K. Rapid Synthesis of Silver Nanowires. 2007 NNIN REU Program, Seattle, WA, 2007; 28-29.

Polyol Method: Silver nitrate is reduced by ethylene glycol in the presence of poly(vinylpyrrolidone) (PVP) and copper(II) chloride. PVP acts as a stabilizing agent, while the copper chloride likely controls the rate of silver reduction and initial seed formation.

Silver Nanowire Synthesis

Bentley, A. K.; Farhoud, A. B.; Ellis, A. B.; Lisensky, G. C.; Crone, W. C. J. Template Synthesis and Magnetic Manipulation of Nickel Nanowires. J. Chem. Educ. 2005, 82, 765-767.

Template-Assisted Nanowire Synthesis

1. To provide a simple and low-cost experiment that allows introductory nanotechnology students to become familiar with micro- and nanofabrication (direct-printing methods) with real-world relevance.

3. To introduce students to template modification.

2. To provide students with opportunities to use various characterization techniques.

Objectives

Microcontact-Printing of PVP GridENGR 1050: Introduction to Nanotechnology

Bright-Field MicroscopyMSE 1820: Fundamentals of Microscopy

Conductive AFMMSE 2320: Introduction to Scanning Probe Microscopy

Associated Labs

Publication

Sanders. W. C.; Fabrication of Polyvinylpyrrolidone Micro-/Nanostructures Utilizing Microcontact Printing. J. Chem. Ed. 2015, 92, 1908-1912.

Publication

Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

“Soft” organic materials are used to transfer patterns to substrates.

Conformal contact: Stamp is elastic enough to conform to the substrate.

Soft Lithography

10 g of silicone elastomer

0.9 g of curing agent

Mix for one minute

Preparing PDMS Stamps

Microcontact Printing Master

AFM image of compact disk.

1. Cut a CD square

2. Remove labels

3. Place CD in a shallow dish

4. Pour PDMS over CD*

5. Remove stamp from dish

*PDMS is cured on a hot plate for 15-20 minutes

Preparing PDMS Stamps

Binder in many pharmaceutical tablets.

Adhesive in glue and hot-melt sticks.

Used to increase the solubility of drugs in liquid and semi-liquid forms.

Found in personal care products (shampoos, toothpastes) and paints.

Polyvinylpyrrolidone

PVP/Silver Ion Interactions

M+

M+

M+

PVP has a strong tendency for complex formation with small molecules and readily interacts with metal cations in solution.

Khan, M. S.; Gul, K.; Rehman, N. U. Interaction of Polyvinylpyrrolidone with Metal Chloride Aqueous Solutions. Chin. J. Polym. Sci. 2004, 22, 581-584.

Challenge 1: PDMS/Solution Interaction

PVP is soluble in water and various alcohols.

Water on PDMS Alcohol on PDMS

Challenge 2: Humidity

Small amounts of water can result in the formation of beaded PVP structures.

Yuya, N.; Kai, W.; Kim, B. S.; Kim, I. S. Morphology Controlled Electrospun Poly(vinylpyrrolidone) Fibers: Effects of Organic Solid and Relative Humidity. J. Mat. Sci. Eng. with Adv. Tech., 2010, 2, 97-112.

Challenge 2: Humidity

The presence of water can also result in the formation of PVP films.

Yuya, N.; Kai, W.; Kim, B. S.; Kim, I. S. Morphology Controlled Electrospun Poly(vinylpyrrolidone) Fibers: Effects of Organic Solid and Relative Humidity. J. Mat. Sci. Eng. with Adv. Tech., 2010, 2, 97-112.

Small traces of water on the surface of stamps and substrates is removed by heating with a hot plate for approximately 10 minutes prior to the experiment.

Challenge 2: Humidity

Procedure:Spin Coat PVP

Procedure:Microcontact-Printing

Procedure:Microcontact-Printing

Procedure:Microcontact-Printing

Procedure:Sputter Coating with Copper

Comparison of cross-sectional data for a PVP grid with no copper layer, and

for the same PVP grid after addition of the copper layer suggests the

thickness of the copper layer is approximately 5 nanometers thick.

Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

Procedures:Metallization

4 Ag+(aq)+ C6H5O7Na3(aq) + 2 H2O(l) → 4 Ag0

(s) + C6H5O7H3(aq) + 3 Na+(aq) + H+

(aq) + O2(g)

Ratyakshi; Chauhan, R. P. Colloidal Synthesis of Silver Nano Particles. Asian J. Chem. 2009, 21, S113-116.

Silver Grid on Glass

Optical Images

Optical microscope image of PVP grid (40x objective)

Optical Images

Optical microscope image of silver grid (40x objective)

AFM Data:Physical Dimensions

Atomic force microscope images of copper-coated PVP grid before the

reaction with silver nitrate/sodium citrate solution (a) and after the reaction

(b). A cross-sectional profile of both AFM scans (c).

Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

SEM Data

EDS scan on and off the silver nanogrid pattern (a). EDS spectra of both

scans (b).Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

SEM Data

Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

Conductivity

Sanders. W. C., Valcarce, R., Iles, P., Smith, J. S.; Glass, G., Gomez, J., Johnson, G., Johnston, D., Morham, M., Beefus, E., Oz, A., Tomaraei, M.; Printing Silver Nanogrids on Glass. J. Chem. Ed. 2017, 94, 758-763.

Acknowledgements

SLCC Chemistry Department

SLCC Engineering Department

Dr. Peter Iles

Ron Valcarce

Dr. James Smith

Joven Calara

Gabe Glass

Jesus Gomez

Glen Johnson

Aimee Oz

Maclaine Morham

Mohammad Tomarei

Aubrey Lines

Myles Van Weerd

John Meyers

Davies Young

Cristofer Page

Kyle Salisbury

Dan Johnston

Elliot Befus