Bengaluru scientists have found a toxic-free technique for converting carbon dioxide (CO2), the most prevalent greenhouse gas (GHG), to methane (CH4), the cleanest fossil fuel, a process that may successfully aid in decreasing atmospheric CO2 levels, which is a key climate change problem.
The transformed CH4 may be employed as a hydrogen carrier in fuel cells right away. It is also the principal component of natural gas, and it has the potential to replace coal in the creation of power and to give energy to renewable generators.
Scientists from Bengaluru’s Jawaharlal Nehru Centre for Advanced Scientific Research (JNCASR) did this utilising a non-metal catalyst, as opposed to current processes, which have been shown to produce harmful fumes throughout the process.
The scientists, lead by Professor Tapas Kumar Maji of JNCASR’s Chemistry and Physics of Materials Unit, have developed a cost-effective metal-free catalyst to accomplish conversion through visible light absorption.
CO2 may be decreased in a number of ways, including photochemical, electrochemical, photoelectrochemical, and photothermal processes. Solar light is used as a sustainable energy source in the photochemical process.
Light-harvesting property, separation proficiency, and the existence of a properly electrically oriented conduction band are some of the fundamental prerequisites for converting CO2 into value-added compounds like CH4, according to JNCASR scientists.
However, reducing CO2 to CH4 selectively and effectively is a hurdle. Only a few catalysts are capable of selectively and effectively reducing CH4, however, the majority of these catalysts involve poisonous and costly metals.
To address this issue, JNCASR researchers created a metal-free porous organic polymer that absorbs visible light while also catalysing the CO2 reduction process.
They accomplished this by creating a donor-acceptor combination that yielded a strong, thermally stable conjugated microporous organic polymer that they employed as a catalyst. In this case, a Ketone group with a carbon-oxygen double bond served as a catalytic site instead of other metal-based catalysts in which the metal component carried out the CO2 conversion to value-added products like CH4.
During the catalysis process, a chemical known as conjugated microporous polymer (CMP) was able to ingest CO2 onto its surface owing to its high CO2 intake capacity at room temperature, converting it to methane as a value-added product with no hazardous by-products.
Prof Maji and his colleagues believe that using this low-cost, metal-free technology with a high CH4 generation rate might lead to new strategic approaches to carbon capture and CO2 reduction. The Journal of the American Chemical Society has approved their paper for publication.
Source: The New Indian Express