Spin polarization regulates photocatalytic CO2 into hydrocarbons by Co doped BiOCl

Doping magnetic elements into semiconductors is an effective strategy for manipulating spin-polarized electrons in photocatalysis. This work indicates that the introduction of spin-polarized electrons into BiOCl ultrathin sheets remarkably boosts the efficiency of photocatalytic CO2 reduction by doping BiOCl with magnetic Co. The Co-doped BiOCl (Co-BiOCl) photocatalyst selectively converts CO2 into CH4 and C2+ products with a hydrocarbon selectivity of 76.9 %, which is not available for pristine BiOCl. The spin-polarized electrons generated from Co-BiOCl promote CO adsorption, stabilize the key CO* intermediate, and significantly reduce the kinetic barrier to CH2* formation, tuning the subsequent hydrogenation and C−C coupling into hydrocarbons. The regulatory effect of spin polarization on photocatalytic CO2 reduction can also be observed for Fe-, Ni- or non-magnetic element Cu- doped BiOCl. Hence, this work provides new insight into the regulation of the photoreduction of CO2 to hydrocarbon products by spin-polarized electrons.