About this Abstract |
Meeting |
2025 TMS Annual Meeting & Exhibition
|
Symposium
|
Advances and Discoveries in Non-equilibrium Driven Nanomaterials and Thin Films
|
Presentation Title |
Ordered nanocrystals induced efficient phase transformation in atomically-thin 2D-MoS2: A new paradigm of hydrogen generation and molecular sensing |
Author(s) |
SANTANU DAS, Ummiya Qamar |
On-Site Speaker (Planned) |
SANTANU DAS |
Abstract Scope |
We synthesized ordered gold-copper (Au3Cu) alloy nanocrystals (~10 nm) and utilized them in the phase transformation of atomically thin large-area 2D-MoS2. Comparing overpotential and Tafel slopes for the Hydrogen Evolution Reaction, we observed a reduction in overpotential by 83.2 mV and a decrease in Tafel slope by ~58.25 mV/decade for Au3Cu/MoS2 under light irradiation. This enhancement in electrocatalytic activity of Au3Cu/MoS2 resulted from the transformation of semiconducting to a metallic phase under light, which altered the surface electronic structure, increased carrier concentrations and reduced the free energy of H* adsorption/desorption. We also demonstrated that the Au3Cu/MoS2 can be used for methylene blue and dopamine detection. DFT calculations and surface characterizations further demonstrated that the ordered nanocrystals induced phase transformation in 2D-MoS2, resulting in more durable metallic characteristics, enhanced surface electrical conductivity, reduced surface potential and Gibbs free energy, and improved kinetics of the photoelectrocatalytic performance of the hybrid structure. |
Proceedings Inclusion? |
Planned: |
Keywords |
Thin Films and Interfaces, Nanotechnology, Electronic Materials |