A review on photochemical, biochemical and electrochemical transformation of CO2 into value-added products

Carbon dioxide (CO2), a greenhouse gas is considered to contribute significantly to climate change and global warming. Environmental changes require to minimize the measure of CO2 in air. The capture, storage and utilization of carbon based on photochemical, biochemical and electrochemical processes are the innovative proposed methods to decrease utilization of nonrenewables such as coal and oil. CO2 can be reduced chemically through either homogeneous or heterogeneous pathway. In general, photochemical transformation of CO2 involves formation of carrier charges followed by its separation, transportation and finally reduction of CO2 using generated photoelectrons. Photocatalytic reduction of carbon dioxide is a rising territory of research. Beginning from the premise of photocatalytic reduction, the investigations about different semiconducting frameworks like oxides, sulfides, and phosphides are considered in this review. Biochemical transformation deals with enzymatic conversion of CO2 and electrochemical reduction uses electrical energy for converting CO2 into its reduced form. The enzyme catalytic carbon dioxide change gives an eco-accommodating approach to make carbon-based chemical products. A few favorable circumstances related with enzymatic change incorporate high selectivity, high return, less quantity of waste, less response conditions however certain downsides, for example, staggering expense of catalysts and cofactors, and longer response times as contrasted and normal strategies. Some products obtained as a result of CO2 reduction includes methanol, formic acid, CO, methane, ethylene and gasoline. In this review, a overview on inalienably associated methodologies is given and ongoing advancement on the improvement, designing, and comprehension of CO2 reduction using photochemical, biochemical and electrochemical is outlined.