Chiral-Induced Spin Selectivity in Photocatalysis: Fundamentals and Emerging Opportunities

Chiral-induced spin selectivity (CISS) has emerged as a rapidly advancing frontier in catalysis research. Incorporating chirality─particularly through the CISS effect─into photocatalytic systems offers a pioneering strategy to achieve spin polarization and enhance charge separation. This review provides a comprehensive overview of the distinctive roles of the CISS effect in photocatalysis, elucidating its underlying mechanisms, rational design principles, and state-of-the-art characterization strategies. We further highlight applications of chiral photocatalysts in energy conversion and environmental remediation, including the hydrogen evolution reaction (HER), oxygen evolution reaction (OER), and CO2 reduction reaction (CO2RR). Furthermore, this review predicts highly promising chiral photocatalysts and highlights the transformative potential of coupling the CISS effect with magnetic fields to synergistically regulate spin, as well as to address key challenges such as microplastic degradation, biomass valorization, and light-assisted metal–air batteries. By integrating chirality with spin-selective processes, this review underscores opportunities for advancing photocatalytic technologies toward energy and environmental solutions.