A review on catalyst advances for photothermal dry reforming of methane reaction

Abstract

Dry reforming of methane (DRM) converts the greenhouse gases of methane and carbon dioxide to useful chemical intermediates of syngas, contributing to both environment and energy. However, the high bond energies of C–H in methane and C=O in carbon dioxide result in the endothermicity of DRM, requiring high temperature for considerable conversions of carbon dioxide and methane in conventional thermal DRM. This causes problems of carbon deposition and catalyst sintering. Recently, the photothermal DRM are demonstrated needing lower temperature than thermal DRM, significantly enhancing performance, reducing carbon deposition and minimizing sintering. These are owned to the synergistic contribution from both photo and temperature, which reduces activation energies of methane and carbon dioxide, increases surface temperature of catalyst and adjusts reaction path ways etc. in photothermal DRM. To have an overview achievement of photothermal DRM in recent years, this paper reviews catalyst developments and mechanism investigations for photothermal DRM. We firstly introduce the active sites and principles in photothermal DRM, then the latest development of catalysts including TiO2-, CeO2- C3N4-, SiO2-based catalysts, layered double hydroxide catalysts and single atom catalyst are summarized. After illustrating the reaction mechanism, the outlook of possible investigation is suggested in future. It is hoped that this paper could provide pioneers useful guidance developing catalyst for photothermal DRM, as well as other photo-sensitive reactions.