Group meeting

Group Meeting

Literature

Emission Enhancement and Chromism in a Salen-Based Gel

SystemPeng Chen, Ran Lu, Pengchong Xue, Tinghua Xu, Guojun Chen,

Yingying Zhao

Ran Lu• Jilin University• State Key Laboratory of

Supramolecular Structure and Materials

• 130 papers on Sci-Finder• 9 Mater. Chem. Phys.• 5 Langmuir• 5 J. Mater. Research• Various other ACS papers

Emission Enhancement and Chromism in a Salen-Based Gel

System• Functional gelsenhanced charge

transport, fluorescence, catalysis, sensing abilities

• States that: “self-assembled properties of metal-salen complexes remains unexplored in the field of gels, although…”

J Aggregates

• Salphen aggregates exhibit J-bands (bathochromic shift)

• What about a gel system with thermochromism properties, based on salphen/salen type molecules with various metals?

The Molecule

• Cholesterol-containing salen-based gelator• Excellent organogelator in cyclohexane,

benzene, toluene, other mixed solvents

The SEM etc.

Reversible

• Cyclohexane gel = Colourless hot solutionyellow gel (as cooling)

• UV-Vis: Hot = 297 nm, 334 nm

• UV-Vis: RT = 480 nm

Reversible

Photochromism

• Irradiation of cyclohexane gel with 365 nm light with variable irradiation times

Fluorescence

• Fluorescence quantum yield is 600 times greater in gel than in solution 10-4 10-2

Summary

• New salen-based organogelator• Gels in several solvents• Moleculenanofibers3-D network• Aggregation-induced emission

enhancement (AIE) J-aggregates + no intramolecular rotation

• Solutionfaint blue; Gelbright green• Reversible chromism due to NH/OH

tautomerism

Supramolecular Assembly via Noncovalent Metal Coordination

Chemistry: Synthesis, Characterization, and Elastic

Properties

Christina Ott, Johannes M. Kranenburg, Carlos, Guerrero-Sanchez,Stephanie Hoeppener, Daan Wouters, Ulrich S. Schubert

Ulrich S. Schubert• 710 papers on Sci-Finder• 92 Polymer Pre-prints• 55 Macromol. Rapid Comm.• 20 Macromol. Chem. Phys.• 17 Macromolecules • 13 Adv. Mater.• 12 Soft Matter• 12 J. Mater. Chem.• 9 J. Comb. Chem.• 2 management assistants, 9 supporting

technical staff members, 9 guests (Dr.), 18 post-docs, 23 PhD students, 7 undergrads

Supramolecular Assembly

• Block co-polymers linked by Ru(II) complexes• Change elastic modulus of material by varying

chemical composition

Synthesis

• Styrene co-polymersinert atmosphere; 1,1-diphenylethylene + sec-butyllithium in cyclohexane (turn red) + styrene; then added 4’-chloro-2,2’:6’,2’’-terpyridine = SPSn-[

Synthesis A-Ru-B

Synthesis A-Ru-B-Ru-A

Micelles

• Polymers dissolved in THF and H2O added dropwise to induce aggregation of insoluble SPS block. More water added to “freeze” micelles.

• SPS39-[Ru]-PEG70

Structure-to-Function

• Flory-Huggins interaction parameter

• Volume fraction• Tailor mechanical properties by varying

block size

Structure-to-Function

Structure-to-Function

Structure-to-Function

• Indentation-load displacement response

Structure-to-Function• Increased % SPS = Increased stiffness• Decreased % [Ru], % PF6

- counterions• Humidity check