Uranium-Incorporated Layered Perovskitoids with Heterostructures Exhibit Hole-Dominant Transport

Abstract The bottom-up synthesis of bulk single crystals with intrinsic heterostructural electronic behavior has attracted attention, yet examples exhibiting hole-dominated transport remain exceedingly rare. Herein, we report a uranium-incorporated layered perovskitoid, representing the first actinide-based single-crystal heterostructure with intrinsic hole-dominated transport. [(UO2)GABA3]4[Pb11Br28]Br2∙2H2O (GABA = protonated γ-aminobutyric acid, (COO–)CH2CH2CH2NH3+) is synthesized via solution assembly of a preformed uranyl-aminobutyric complex, [(UO2)GABA3]NO3Br∙3H2O, with PbBr2. The uranyl-aminobutyric complex units act as interlayer spacers between the semiconducting perovskitoid slabs. Importantly, the unfilled 5f/6d orbitals of the uranyl moiety insert energetically into the band structure of the perovskitoid slabs, creating a staggered gap structure that facilitates hole-dominated behavior. This compound exhibits a hole mobility of 0.45 cm2·V–1·s–1 with a hole-to-electron mobility ratio of ∼3.5. This work not only expands the compositional space of single crystal heterostructures but also highlights the untapped potential of 5f elements in engineering charge transport for high-performance electronic materials.