chemicals. Reduction reactions involving more than two electrons and two protons can produce formaldehyde (HCHO), methanol (CH3OH), and methane (CH4), which are also desirable as chemicals and fuels. For molecular electrocatalysts, more negative potentials than the equilibrium ones for CO2 reduction are generally required; the difficulty is that the equilibrium potentials for CO2 reduction are generally negative of the equilibrium potential for proton reduction to produce H2, representing a competing thermodynamically favored process. A complementary approach to an electrochemical one is to mediate CO2 reduction with photo-induced electron transfer reactions. Photo- and electrocatalytic CO2 reduction can be used to achieve artificial photosynthesis, or the production of commodity chemicals and fuels with renewable energy inputs originating from solar sources. This Research Topic covers the molecular catalysts based on coordination and organometallic compounds for CO2 fixation/reduction. It includes chemical, electrochemical, and photochemical reactions. It also covers systematic studies of reaction mechanisms and the spectroscopic characterization of catalytic intermediates. Molecular catalysts for CO2 fixation/reduction used as co-catalysts with heterogeneous catalytic systems are also included. Non-precious and abundant transition metal catalysts for CO2 fixation/reduction are important for future industrial applications as core components of the next generation of energy technologies. |