Harvesting the Sun's Full Potential via Broadband Absorbers for Efficient Photocatalysis

Broadband absorbers have emerged as promising photocatalysts for maximizing solarenergy utilization by harvesting photons across the ultraviolet, visible and near-infrared regions of the solar spectrum. However, enhanced spectral absorption does not necessarily translate into improved photocatalytic performance, as it is often accompanied by accelerated charge-carrier recombination and diminished redox driving force. Therefore, understanding how absorbed photons are converted into reactive charge carriers and subsequently utilized in surface catalytic reactions is crucial for advancing broadband photocatalysis. In this review, beyond viewing broadband absorption as a purely optical property, the underlying mechanisms linking broadband light harvesting to catalytic activity are systematically discussed via various representative systems, including metasurface-reflective metal nitride-based heterostructures, non-metallic plasmonic antenna-reactor-hot core patterns, semimetallic catalyst, inorganic-organic heterostructure and pure organic broadband absorbers. Such a framework enables a more comprehensive understanding of how broadband light absorbers influence photocatalytic reactions, providing rational guidelines for the design and development of highly efficient solar-driven catalytic systems.