Photocatalytic and Thermo-Photocatalytic Processes: Advantages of Modelling Light Irradiation and Temperature Profiles

This contribution presents a personal perspective on the development of thermo-photocatalytic schemes. It discusses several concepts focused on the common presentation of catalytic and thermo-photocatalytic data, with special emphasis on the determination of TOF (Turnover Frequency) and Quantum Efficiency parameters. The importance of including temperature profiles and photon absorption rates in the analysis for intrinsic kinetic studies, comparison of catalytic results, and the potential scaling of reactors is highlighted. Additionally, topics related to the efficiency of the use of radiation and heat transfer are discussed. Photon absorption profiles are presented for a TiO2 catalytic surface of 20 × 20 cm (both fluorescent and LED configuration), as well as the temperature profile obtained using a thermal resistance with a diameter of 5 cm in a flat reactor. Using this example, the importance of designing thermo-photocatalytic systems to ensure an acceptable level of homogeneity in light irradiation and temperature is discussed. The discussion provides data that positions thermo-photocatalytic processes in the early stages of research. It is still necessary to advance the understanding of phenomena occurring under mixed temperature and light conditions. Additionally, new materials that meet the required characteristics for each application need to be developed, along with the design of new thermo-photocatalytic reactors.