Magnetic-field-dominated spin-driven lattice deformation of 2D FeO/Cu2O composites for CO2 photocatalytic C-C coupling

Spin is an important degree of electronic freedom that can be uti-lized to design new materials and possibly even construct new mat-ter states. This study demonstrates that the transition of Fe outer electrons from the low-spin state to the high-spin state can be trig-gered by applying a magnetic field during the deposition of Fe on Cu2O. Magnetic-field-dominated spin rearrangement drives the directional splitting of the Fe d orbital and promotes the interphase oxygen migration of Cu2O to surface reconstruct the Cu clusters attached to the 2D FeO materials. The spin-driven 2D FeO/Cu2O material featured dual active sites, which could realize C-C coupling during the photoreduction of CO2 to ethanol with an outstanding yield and selectivity of as high as 9.69 mmol g-1 h-1 and 60.8%, respectively. Our results demonstrate the important role of spin regulation in the design of photocatalytic materials and open up a new pathway for inorganic synthesis.