Spin-polarized charge transfer in a Z-scheme Mn: CsPbBr3/Zinc phthalocyanine heterojunction for efficient CO2 photoreduction

Advanced photocatalytic architectures for sustainable CO 2 reduction encounter two significant challenges involving severe electron-hole recombination and limited active sites. Herein, we synthesize a Z-scheme heterojunction composing of Mn-doped CsPbBr 3 nanoplatelets (Mn-CPB) and zinc phthalocyanine (ZnPc) via self-assembly. Mn 2 + doping in CsPbBr 3 induces spin polarization, creating spin-polarized hot electrons. These electrons transfer via the Z-scheme interface to ZnPc’s Zn 2+ center, thereby enhancing photocarrier separation and mobility and promoting CO 2 adsorption-activation. The heterostructure achieves an exceptional CO evolution rate of 15.17 μmol g −1 h −1 with 78.31 % selectivity, surpassing the performance of individual components under visible light. In-situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) and density functional theory (DFT) calculations confirm the formation of key intermediates (•CO 2- ) during CO 2 adsorption and reduction. This work presents a strategy integrating spin regulation with interfacial band alignment, advancing perovskite-derived photocatalysts for solar-to-chemical conversion.