Enhancing C–C Bond Cleavage of Glycerol Electrooxidation through Spin‐selective Electron Donation in Pd–PdS2–Cox Heterostructural Nanosheets

As a 4d–transition metal, the spin state of Pd is extremely difficult to directly regulate for the optimized d orbital states owing to the strong spin–orbit coupling effect and further extended d orbital. Herein, we devise "spin–selective electron donation" strategy to tune specific d orbital electrons of Pd inspired by Dewar−Chatt−Duncanson model theory. Co−S−Pd bridges with different spin–states of CoIII have been constructed in a series of Pd–PdS2–Cox HNSs with tunable Co content. Experiments and theoretical calculations indicate that low‐spin CoIII (t2g6eg0) with fully occupied t2g orbitals and empty dz2 orbital can accurately alter the dz2 electron of Pd by σ–donation via Co−S−Pd bridge. In contrast, unfilled dxy orbital of high‐spin CoIII (t2g5eg1) is essential for controlling the dxy electron of Pd via π–donation. Benefiting from dz2 state optimization by σ–donation, Pd–PdS2–Co4.0 delivers superior performance towards various bio–alcohols (ethanol, ethylene glycol and glycerol) with enhanced C−C bond cleavage. Furthermore, coupling glycerol oxidation reaction with CO2 reduction reaction (GOR||CO2RR), the electricity consumption of GOR||CO2RR drops 46.4% compared to the state−of−art system (OER||CO2RR). Moreover, anodic Faraday efficiency (FE) of formic acid can be attainable more than 90% at low voltage region.