Nanocatalyst converts greenhouse gas into green fuel
doi:10.1038/nindia.2020.128 Published online 26 August 2020
Researchers from the Tata Institute of Fundamental Research (TIFR) in Mumbai have synthesised ‘nanosilica’, a silica-based, reusable metal-free nanocatalyst that can convert carbon dioxide into methane, a potential green fuel1.
This nanocatalyst could potentially be used to reduce the levels of atmospheric carbon dioxide, a potent greenhouse gas that contributes to global warming.
Methane can be produced through reactions between carbon dioxide and hydrogen. But, existing methods require expensive catalysts for such methane-producing reactions.
In search of an efficient and cheaper method, the TIFR scientists, collaborating with researchers from the Indian Association for the Cultivation of Science in Kolkata, prepared the metal-free silica-based nanocatalyst using a specific process that creates structural defects on its surface. They then tested the nanocatalyst’s efficiency in converting carbon dioxide into methane.
The researchers, led by Vivek Polshettiwar, found that the defects in the catalyst acted as catalytic sites and played vital roles in producing methane from carbon dioxide.
The catalyst, they found, can be regenerated simply by heating it in the air. After every 24-hour reaction cycle, the regenerated catalyst’s catalytic activity increased significantly. The catalytic activity saturated after eight regeneration cycles, when the methane production rate was more than double that of the initial production rate.
The nanosilica remained active and stable for more than 200 hours. Such activity and stability were much better than conventional metal catalysts.
1. Mishra, A. K. et al. Defects in nanosilica catalytically convert CO2 to methane without any metal and ligand. P. Natl. Acad. Sci. USA. 117, 6383-6390 (2020)