CO2 Hydrogenation Catalyzed by Graphene-Based Materials

Abstract

In the context of an increased interest in the abatement of CO2 emissions generated by industrial activities, CO2 hydrogenation processes show an important potential to be used for the production of valuable compounds (methane, methanol, formic acid, light olefins, aromatics, syngas and/or synthetic fuels), with important benefits for the decarbonization of the energy sector. However, in order to increase the efficiency of the CO2 hydrogenation processes, the selection of active and selective catalysts is of utmost importance. In this context, the interest in graphene-based materials as catalysts for CO2 hydrogenation has significantly increased in the last years. The aim of the present paper is to review and discuss the results published until now on graphene-based materials (graphene oxide, reduced graphene oxide, or N-dopped graphenes) used as metal-free catalysts or as catalytic support for the thermocatalytic hydrogenation of CO2. The reactions discussed in this paper are CO2 methanation, CO2 hydrogenation to methanol, CO2 transformation into formic acid, CO2 hydrogenation to high hydrocarbons, and syngas production from CO2. The discussions will focus on the effect of the support on the catalytic process, the involvement of the graphene-based support in the reaction mechanism, or the explanation of the graphene intervention in the hydrogenation process. Most of the papers emphasized the graphene’s role in dispersing and stabilizing the metal and/or oxide nanoparticles or in preventing the metal oxidation, but further investigations are needed to elucidate the actual role of graphenes and to propose reaction mechanisms.

Applications of Al2O3‐Based Nano‐Catalysts in Thermocatalytic CO2 Transformations: Impacts of Surface Acidity and Basicity

“…Recent works mainly focus on specific reaction system, [65][66][67][68][69][70][71] electrolytic CO 2 conversions, [72][73] photo-enhanced CO 2 transformations, [20,[74][75][76] microwave-assisted CO 2 conversions, [77] plasma-assisted CO 2 utilizations, [78] CO 2 adsorbents and sorption, [79][80] support effects, [81] CeO 2 -based catalysts, [82] Nibased catalysts, [83][84][85][86] zeolite-based catalysis, [87] graphene-based materials, [88] Cr-free metal catalysts, [89] bimetallic catalysts [90] and perovskite catalysts. [22] Different from the previous review works related to CO 2 capture and transformation (Table 1), in this work, the major contents are based on comprehensively summarizing the modification strategies for optimizing the surface acidity and basicity of Al 2 O 3 -based metal catalysts, which in turn determines the CO 2 adsorption, activation and conversion in a series of CO 2 -involved thermocatalytic processes.…”

Promotional Effects on the Catalytic Activity of Co-Fe Alloy Supported on Graphitic Carbon for CO2 Hydrogenation

“…In recent years, the use of graphene-based solids as catalysts for CO 2 hydrogenation has attracted much attention [31]. For example, a Pd-embedded g-C 3 N 4 /reduced graphene oxide (rGO) aerogel (Pd-g-C 3 N 4 /RGOA) photocatalyst was reported for the reduction of CO 2 to CH 4 [32].…”