Enhancement of photocatalytic CO2 reduction in BiOBr through chirality-induced electron spin polarization regulation

Abstract

Severe photogenerated charge carrier recombination involved in photocatalytic CO₂ reduction leads to low photocatalytic efficiency. Here we demonstrate that a chiral hierarchical structure could facilitate charge separation in BiOBr, thus suppressing charge recombination and enhancing photocatalytic performance. Chiral helical flower-like BiOBr nanospheres were prepared via a D/L-sorbitol-assisted hydrothermal process, exhibiting a 1.1-fold increase in photocatalytic CO₂ reduction activity compared to the achiral counterparts. This enhancement is attributed to the chiral-induced electron spin polarization regulation, as confirmed by photoluminescence and electrochemical characterizations. This work opens an alternative avenue for the design of high-performance photocatalysts.