This project focused on developing and testing advanced 2D transition metal compound (TMC) catalysts for efficient hydrogen production via water splitting, exploring materials such as WS2/Ti3C2, Mo2S3-WS2, and TM1/3NbS2. Key activities and achievements are outlined below:
1. Synthesis of 2D TMC Catalysts
Synthesized WS2/Ti3C2 and Mo2S3-WS2 using chemical methods, enhancing charge transfer and catalytic efficiency.
Developed TM1/3NbS2 (TM = Fe, V, Cr, Mn, and Co) via chemical vapor transport, incorporating various metals to optimize performance.
2. Electrochemical Testing
WS2/Ti3C2: Demonstrated low overpotentials (92-260 mV for HER, 430-690 mV for OER at 100-500 mA/cm²) and photocatalytic activity (~33 μA/cm² for HER, ~120 μA/cm² for OER).
Mo2S3-WS2: Achieved low overpotentials (145 mV HER, 420 mV OER electro; 92 mV HER, 310 mV OER photo) and high current density (1 A/cm² at 2.07 V, RT).
Fe1/3NbS2: Delivered exceptional bifunctional activity with stable high current densities (0.5 - 2 A/cm²) and low cell voltages, maintaining performance over 700 hours (RT) and 220 hours (60 °C).
Long-Term Stability: An AWE single-stack system in a zero-gap configuration, utilizing Mo2S3-WS2 electrodes, demonstrated exceptional stability over 500 hours of continuous operation at 0.5 mA/cm² and that integrated with Fe1/3NbS2 maintained stable potentials at high current density of 1000 mA/cm² for extended durations of 700 hours at room temperature and 220 hours at 60 °C.
3. Integration with Renewable Energy Systems
• Coupled Mo2S3-WS2 electrolyzer with silicon solar cells, achieving ~0.8 A/cm² at 2 V, showcasing renewable energy compatibility.
4. Photocatalytic Activity Exploration
• Photocatalytic Testing: This project marked the first demonstration of photocatalytic hydrogen production using WS2/Ti3C2 and Mo2S3-WS2 TMCs.
Outcomes and Achievements
The project successfully demonstrated the following key outcomes:
Efficient Catalysts: Developed 2D TMCs exhibited superior bifunctional performance.
High Performance: Mo2S3-WS2 and Fe1/3NbS2 electrolyzers demonstrated high stability, scalability, and efficiency.
Renewable Energy Integration: Showcased feasibility of coupling hydrogen production with solar energy.
Photocatalysis: Pioneered light-driven hydrogen production with WS2/Ti3C2 and Mo2S3-WS2 (Also, first to report in these materials).
Conclusion
The project achieved significant advancements in 2D TMC catalysts, demonstrating high performance, stability, and scalability for hydrogen production, including integration with renewable energy systems. These developments position the materials as promising solutions for clean, sustainable energy.