World is facing problems of global warming as well as energy crisis. Both these problems can be solved to a reasonable extent by photoreduction of carbon dioxide. Here, photocatalysis enters the scene. Photocatalytic reduction to synthetic organic fuels like formaldehyde, methanol, formic acid, acetic acid, methane, etc. will provide a solution to the problem of energy crisis as it will give us alternate fuels, which can be burnt into fuel cells to generate electricity. Once we get electricity at the cost of carbon dioxide, one can convert this form of energy to any other form of energy. Secondly, it will give a solution to put a check on the increasing amount of carbon dioxide, which is the main culprit of global warming. Any conventional fuel on burring will add some molecules of carbon dioxide in the atmosphere, but synthetic fuels derived by photocatalytic reduction of carbon dioxide will not add even a single molecule of carbon dioxide in the environment. It can be considered as a short term loan of carbon dioxide from the atmosphere as the carbon dioxide molecules utilized in the synthesis of alternate fuels are generated back on burning it in fuel cell.
Selective visible-light driven highly efficient photocatalytic reduction of CO2 to C2H5OH by two-dimensional Cu2S monolayers
