Design, Synthesis, and Characterization of a Porous Ceramic-Supported CeO2 Nanocatalyst for COx-free H2 Evolution

Abstract

The use of fossil fuels threatens environmental systems and causes an increase in greenhouse gas emissions, thereby leading to global warming. Such a scenario has spurred research into renewable hydrogen energy production as a strategy to replace fossil fuels. In this regard, thermochemical water splitting using redox reactions with metal oxides, which generates neither CO nor CO2 gas, is a promising approach with advantages over general hydrocarbon steam reforming. However, preventing catalytic deactivation due to nanocatalyst agglomeration or sintering during thermocycling at high temperatures (>800 °C) is a significant challenge. In this work, the design, synthesis, and characterization of a new CeO2-based catalytic model were carried out through a combination of theoretical and experimental approaches. From thermodynamic simulations, an optimal support material was first selected. A CeO2 nanoparticle-dispersed porous support structure was subsequently synthesized. The recyclable CeO2–support structure showed good capability and repeatability for hydrogen generation during consecutive thermocycles with no undesirable side reactions or particle sintering. It is anticipated that the results of this study will facilitate greater efficiency in the development of catalytic materials and allow for more effective materials to be designed so as to accelerate the realization of economical green energy production based on thermochemical cycles.