Charge Reservoirs in an Expanded Halide Perovskite Analog: Enhancing High‐Pressure Conductivity through Redox‐Active Molecules

As halide perovskites and their derivatives are being developed for numerous optoelectronic applications, controlling electronic doping remains a fundamental challenge. Herein, we describe novel strategy of using redox-active organic molecules as stoichiometric electron acceptors. The cavities in the new expanded perovskite analogs (dmpz)[Sn2X6], (X=Br− (1Br) I− (1I)) occupied by dmpz2+ (N,N′-dimethylpyrazinium), with LUMOs lying ca. 1 eV above valence band maximum (VBM). Compressing metal-halide framework drives up VBM 1I relative to dmpz LUMO. conductivity increases factor 105 pressure, reaching 50(17) S cm−1 at 60 GPa, exceeding high-pressure conductivities most perovskites. This enhancement is attributed an increased hole density created reduction. work elevates role cations 3D metal-halides, from templating structure serving charge reservoirs tuning carrier concentration.