Photocatalytic nanomaterials: present and future

Abstract

Photocatalysis is a sustainable and light-driven technology increasingly recognized for its potential to address pressing environmental and energy challenges. Incorporating nanomaterials has notably enhanced photocatalytic performance by offering high surface area, tunable optical and electronic properties, and increased chemical reactivity. This review summarizes recent developments in photocatalytic nanomaterials, with a focus on titanium dioxide due to its cost-effectiveness and stability, along with other materials such as zinc oxide, metal sulfides, carbon-based nanomaterials (e.g., fullerenes, nanotubes, graphene, graphitic carbon nitride), perovskites, and metal–organic frameworks. Strategies to enhance photocatalytic activity include bandgap engineering for visible-light activation, suppression of charge carrier recombination through heterostructure formation, and using cocatalysts. Applications span environmental remediation (e.g., water and air purification, soil decontamination) and energy-related processes (e.g., hydrogen generation, CO ₂ reduction, biomass conversion). Despite considerable progress, challenges remain in long-term stability, full-spectrum light absorption, testing standardization, scalability, and potential environmental toxicity. Future research directions involve developing advanced hybrid systems, integrating with energy storage technologies, utilizing artificial intelligence for material design, and implementing green synthesis methods. These developments aim to overcome current limitations and advance the practical implementation of photocatalysis based on nanomaterials in sustainable environmental and energy solutions.