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Chiral Pb(Sn)‐I hybrid organic–inorganic perovskites exhibit outstanding chiral‐induced spin selectivity (CISS) performance, but the nontoxic lead‐free hybrid materials with high stability are still greatly desired for spin filtering in spintronic applications. We synthesize chiral hybrid copper halides (R/S‐MBA)2CuX4 (MBA=methylbenzylammonium; X=Cl, Br) with characteristic 0D CuX4 tetrahedral structural motifs, combining the low toxicity of Cu2+ and air stability of halide ions (Cl− and Br−). Despite similar structural and electronic features, (R/S‐MBA)2CuBr4 shows much smaller chiroptical activity than the chloride counterpart. Magnetically conductive atomic force microscopy measurements display a typical spin‐polarized charge‐transport property with high efficiency up to 90 % for both copper halides. Our work expands the CISS effect into eco‐friendly and stable metal–organic halides, which is promising for applications in spintronics based on transition‐metal hybrid systems. [ABSTRACT FROM AUTHOR]

Abstract: The oxygen evolution reaction (OER) is an ideal model to study the relationship between the activity and the surface properties of catalysts. Defect engineering has been extensively developed to tune the electrocatalytic activity for OER. Compared to the anion vacancies in metal oxides, cation vacancies are more challenging to selectively generate, and the insight into the structure and activity of cation vacancies‐rich catalysts are lacked. Herein, using SnCoFe perovskite hydroxide as a precursor, abundant Sn vacancies on the surface were preferentially produced by Ar plasma. Sn vacancies could be preferentially produced as confirmed by the X‐ray absorption spectra, probably owing to the lower lattice energy and weaker chemical bonds of Sn(OH)4. The Sn vacancies promoted the exposure of active CoFe sites, resulting in an amorphous surface layer, modulated the conductivity, and thus enhanced the OER performance. [ABSTRACT FROM AUTHOR]