Indian scientists discover new catalyst for energy-efficient hydrogen production
Indian scientists have identified a new catalyst that can efficiently oxidise urea and lower the energy demand for the generation of hydrogen by urea-assisted water splitting, thereby making way for improved production of green fuel.
In the backdrop of the importance of hydrogen energy in reversing climate change, the scientific community is intensifying efforts to revolutionise hydrogen production, a key player in the clean energy landscape. Electrolytic generation of hydrogen at the cathode, while inherently clean and green, has been hampered by the energy demands of the oxygen evolution reaction at the anode (counter electrode).
A viable solution emerges from replacing the oxygen evolution reaction with other anodic processes like urea electro-oxidation reaction (UOR) possessing lesser overall cell potential. Adding urea to water has practically been shown to reduce the energy demand for electrochemical hydrogen production by about 30%, the Science and Technology Ministry of India said in a press release.
A team of scientists from the Centre for Nano and Soft Matter Sciences (CeNS) in Bengaluru Nikhil N. Rao, Alex Chandraraj, and Neena S. John have demonstrated a non-noble metal catalyst, Ni3+-rich – Neodymium Nickelate (NdNiO3) with metallic conductivity, that efficiently oxidises urea, thereby lowering the energy demand for hydrogen generation by urea-assisted water splitting.
The team used neodymium nickelate as an electro-catalyst for UOR, and using techniques such as X-ray absorption spectroscopy, electrochemical impedance spectroscopy and Raman spectroscopy performed operando (under operating conditions), substantiated that the catalyst drives the reaction specifically through a 'direct mechanism'.
The direct mechanism exhibited by electrochemically activated neodymium nickelate stands out for its minimal catalyst degeneration and reconstruction, contrasting with the indirect mechanism requiring regeneration after each cycle of UOR that prevails in Ni2+-rich catalysts such as NiO.
The catalyst has superior reaction kinetics (making the reaction faster), and enhanced stability during prolonged electrolysis, which are the attributes of a good electro-catalyst.
Published in ACS Catalysis, a journal dedicated to publishing experimental and theoretical research on catalytic materials, this work could direct future studies. "The marks a significant step towards sustainable and efficient hydrogen production," the Ministry said.