Zigzag Perovskitoids with Superior Stability and Thermal Conductivity

Two-dimensional (2D) layered hybrid perovskites constitute an emerging class of semiconductors with tunable structures and desirable properties, primarily governed by the inorganic sublattice. Octahedral tilting and distortions of the inorganic skeleton, as well as interlayer sliding and stacking, give rise to broken symmetries and are modulated by the organic spacers. The inorganic layers sandwiched between two organic layers typically maintain a planar geometry, but the corrugation of the inorganic slab itself in the out-of-plane direction remains largely unexplored. Here, we report a family of zigzag perovskitoids that exhibit common features in their single-crystal structures along with temperature-dependent lattice behavior. These zigzag perovskitoids exhibit markedly superior stability and thermal conductivity compared with 2D-planar perovskites A_nPbI₄ due to altered soft modes and vibrational behaviors modulated by distinct Pb-I motifs. Their unique optoelectronic properties, governed by the zigzag inorganic sublattice, also suggest promising applications. These findings provide insights into the control of stability, thermal transport, and optoelectronic properties in layered hybrid materials and open up possibilities for low-dimensional perovskite-based thermal management applications.