The solar-to-chemical energy conversion of greenhouse gas CO2 into carbon-based fuels is a very important research challenge, with implications for both climate change and energy security. Herein, the key attributes of hydroxides and oxygen vacancies are experimentally identified in non-stoichiometric indium oxide nanoparticles, In2O3-x(OH)y, that function in concert to reduce CO2 to CO under simulated solar irradiation.
Keywords: carbon dioxide; indium oxide nanoparticles; isotope tracing; photocatalysis; solar fuels.