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Photodeposition of Pd onto Colloidal Au Nanorods by Surface Plasmon Excitation
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Colloidal Phase Control in Plasmonic Metal Oxide Nanocrystals via Competitive Metal-Ligand Equilibria
Jiho Kang1, Dingwen Qian1, Jayoon Lee2
1McKetta Department of Chemical Engineering, University of Texas at Austin, Austin, TX, 78712, USA.
Angewandte Chemie (International Ed. in English)
|November 4, 2025
Summary
Researchers developed a new method to control colloidal nanocrystal gel properties using competitive coordination chemistry. This approach allows tunable infrared optical modulation by adjusting gelation temperature and network structure.
Area of Science:
- Materials Science
- Chemistry
- Nanotechnology
Background:
- Colloidal nanocrystal gels have tunable optical properties based on building blocks and arrangement.
- Reversible molecular linkers control gel phase behavior and structure via bond strength and lability.
- Precise control over these interactions is a significant synthetic challenge.
Purpose of the Study:
- To present a broadly tunable linking strategy for modulating nanocrystal gel phase behavior and assembly structure.
- To achieve programmable control over gelation temperature and network structure.
- To establish competitive coordination chemistry as a versatile platform for engineering dynamic, stimuli-responsive colloidal assemblies.
Main Methods:
- Leveraging competitive metal-ligand equilibria to modulate nanocrystal assembly.
- Tuning competitive metal-terpyridine and metal-halide equilibria in terpyridine-functionalized tin-doped indium oxide (ITO) nanocrystals.
- Utilizing kinetic Monte Carlo and optical simulations to understand structure-property relationships.
Main Results:
- Programmable control over gelation temperature and network structure was achieved by tuning metal and halide identity, concentration, and temperature.
- Wide-range infrared optical modulation was enabled.
- Weaker, more labile links facilitated particle crawling, leading to denser gel structures with enhanced plasmon coupling.
Conclusions:
- The developed strategy offers a simple, broadly tunable method for engineering colloidal nanocrystal gels.
- Competitive coordination chemistry provides a versatile platform for creating dynamic, stimuli-responsive materials.
- This approach eliminates the need for complex ligand or linker design in colloidal assembly.
Keywords:
Colloidal gelDynamic covalent bondingLocalized surface plasmon resonanceMetal coordinationPlasmon couplingMore Related Videos
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