Liquid phase reduction of CO2 using metal-nano structured catalysts

The high increase in the greenhouse gas emissions and depleting fossil fuel reserves and the ever increasing need for more energy, set forth the path to the research on production of renewable fuels. The conversion of solar energy to chemical energy is one of the most sustainable routes for the future energy needs due to its high energy density, easy long-term storage and transport. This created, the opportunity for the research into the thermal, photo-catalytic, and photo-electro catalytic reduction of CO2 under solar irradiation which serves two purposes - 1) greatly increase carbon recycling, 2) reduce fossil fuel consumption. CO2 atmospheric concentration is steadily increasing at a rate of 2 ppm annually. So, it is high time we start reduction in the CO2 emissions. Currently, two ways of producing solar fuels - 1) Liquid phase system 2) Gas phase system are being explored. These two setups, lead to different products and show different efficiencies in the productivity due to the differences in the mechanism which underlay the reactions occurring. Gas phase CO2 reduction has advantages such as ease in recovery of products, no CO2 solubility issues, etc. On the other-hand, Liquid phase CO2 reduction yields in higher productivity. Liquid phase reactions are being performed in a novel modified photo-electro catalytic (PEC) cell. The liquid phase reduction of CO2 yielded formic acid, acetic acid as the major products and trace amounts of methanol. Initial experiments were conducted using copper thin film electrode to study the modified PEC cell. Metal based nano-structured catalysts using Fe, Sn, Cu, Zn, Ni are being synthesized in order to improve the productivity and also, to fine tune the selectivity in achieving longer chain hydrocarbon fuels. References: 1. Chiara Genovese, Claudio Ampelli, Siglinda Perathoner, Gabriele Centi, Journal of Catalysis, 308, 237–249, (2013) 2. Claudio Ampelli, Gabriele Centi, Rosalba Passalacqua and Siglinda Perathoner, Energy Environ. Sci., 3, 292-301, (2010) 3. Kendra P. Kuhl, Etosha R. Cave, David N. Abram and Thomas F. Jaramillo, Energy Environ. Sci., 5, 7050-7059, (2012)