Chiral (BiO) 2 CO 3 catalysts with spin-selective charge transport enhance photocatalytic oxygen evolution

formation. Electrochemically active surface area analysis reveals that samples with stronger chirality possess fewer exposed active sites but higher intrinsic activity per site, indicating that performance enhancement originates from improved single-site reactivity rather than increased site density. These results establish a direct correlation among chiral structure, spin polarization, and catalytic activity, providing a new design principle for spin-regulated high-performance photocatalysts.