Preparation and Characterisation of Photocatalysts for CO2 valorisation in Membrane Reactors

Abstract

Carbon dioxide is a gas that is constantly exchanged among the atmosphere, oceans, and land surface due to its continuous production and absorption by many microorganisms, plants and animals. These processes tend to balance the CO2 content in the atmosphere; however, since the Industrial Revolution, human activities are perturbing this equilibrium causing global warming and climate change. Due to this problem, an increasing concern has bring the scientific community to devote huge efforts to the CO2 reduction and/or valorisation. The published researches demonstrate that photocatalytic reduction of CO2 in the presence of H2O as reductant is a promising green way to obtain CH4, CO, CH3OH, EtOH, HCHO, acetaldehyde, and other products. Albeit, some aspects should be still improved in the use of the current technology, mainly related to the fact that TiO2, the most known photocatalyst, absorbs light in the ultraviolet region of the electromagnetic spectrum and the use of the visible light is by far desirable. Beside the use of the best light source, also the high recombination hole-electron photogenerated charges (h+ e-) should be reduced or, in the best prospective, suppressed. The aim of the current PhD dissertation is the CO2 reduction by renewable methods, by using sunlight in order to obtain molecules that eventually could be used as fuels. This challenge aims to miming the natural process