Theoretical and experimental progress in photothermal catalysis for sustainable energy and environmental protection: Key problems and strategies towards commercialization

In the current energy crisis, converting solar-thermal energy into chemical forms has become paramount. Within the broad spectrum of light-mediated catalysis, which includes heat and photocatalysis (relevant to processes like organic transformations, water splitting, and CO2 reduction), photothermal catalysis is a critical avenue for transforming solar energy into chemical or thermal forms via light-matter interactions. However, challenges persist, notably in conventional semiconductor photocatalysts. These challenges encompass the suboptimal harnessing of solar radiation, electron-hole pair recombination, limited exposure of reactive sites, and the complex endeavor of establishing the structure-activity relationship. This state-of-the-art review sharply focuses on photothermal catalytic materials associated with water splitting, CO2 conversion, and the breakdown of organic contaminants. Distinctively, it provides a profound experimental and theoretical insight into the application of various materials in photothermal catalysis, representing a pioneering consolidation. Furthermore, the article delves deep into the barriers to commercialization, offering a robust discussion of the inherent challenges and their prospective remedies. Our findings underscore that enhancing catalytic efficiency is achievable through strategic structural, surface, and compositional modifications. Techniques such as doping, the formation of heterojunctions using Z- and S- schemes, multi-metal incorporation, and the synergistic application of materials prove beneficial. Equally pivotal is the introduction of supporting materials to curb agglomeration, the incorporation of porosity, and the design of varied 3D structures. Collectively, these innovative approaches enhance surface area, modulate band gaps, widen light absorption capacity, minimize charge recombination, and, consequently, pave the way for the evolution of optimal catalysts suited for photothermal applications.