Efficient & Low-Cost Electro-Catalysts for Rechargeable Metal-Air Battery Developed from Fish Gills

Scientists at the Institute of Nano Science and Technology or INST, Mohali, which is an autonomous institute under the Department of Science & Technology, Government of India, have come up with an efficient, low-cost electro-catalyst from fish gills. This invention of scientists can help to develop environmentally friendly energy conversion devices.

Benefits of Low-Cost Electro-Catalyst from Fish Gills:

The bio-inspired carbon nanostructure can help to overcome the bottleneck in the realization of various renewable energy conversion & storage technologies like fuel cell, bio-fuel cell, & metal-air battery.

This present strategy enriches a route to synthesize low-cost, highly efficient bio-inspired electro-catalyst that is better than commercial Platinum on carbon (Pt/C) catalyst. It could also be utilized as next-generation non-precious carbon-based electro-catalyst for energy conversion and storage applications.

Its results have been recently published in the journal Inorganic Chemistry published by the American Chemical Society, 2020, (DOI: 10.1021/acs.inorgchem.0c00446).

Dr. Ramendra Sundar Dey with his team from INST have explored a highly active Oxygen Reduction Reaction (ORR) electrocatalyst based on binary transition metals Iron (Fe), Manganese (Mn) and N-doped porous carbon (Fe, Mn, N-FGC), derived from fish gills (FG) acquired as animal waste. It has a unique porous structure which could provide conductive carbon networks after heat treatment. At the same time, it could be an efficient electrode material. The catalyst was able to show active oxygen reduction reaction in a wide range of pH (pH < 1, 7, and >13) and outperformed the commercial Pt/C catalyst.

The team fabricated a homemade rechargeable Zn−air battery (ZAB) with the catalyst as an air cathode, & it showed almost stable charge−discharge voltage plateaus after rigorous cycling for a long duration. It also surpassed the commercial Pt/C based ZAB performance. The scientists has found that the reason behind the outstanding performance of this catalyst is due to the presence of Fe−Mn based binary moiety, which is actually beneficial for the Oxygen (O2) binding & boosting Oxygen Reduction Reaction (ORR) catalytic performances in alkaline medium by weakening the Oxygen-Oxygen bonds.

These researchers have suggested that the careful selection of transition metals & heteroatoms together with engineering the synthesis protocol can give a new way for exploring highly active low-cost electrocatalyst for environmentally friendly & efficient energy conversion devices.