Two-dimensional (2D) halide perovskites have garnered significant interest owing to their facile solution processing, high quantum yield, and tunable photoelectronic properties. The formation of lateral heterostructures by 2D halide perovskites offers exceptional electronic and photoelectronic characteristics. However, the stability of 2D halide perovskite lateral heterostructures is compromised by the substantial intrinsic ion migration within the perovskite structure. Consequently, the suppression of ion diffusion at the interface is crucial to enable the growth of stable 2D halide perovskite heterostructures. In this study, we present an innovative polymer bridging strategy for the preparation of 2D halide perovskite lateral heterostructures with enhanced stability. We selected a linear polymer with cyano as the polymer bridge. The Polymers contain a significant number of binding sites that can effectively coordinate with the uncoordinated lead atoms at the in-plane edge of the 2D halide perovskite, thereby providing protection against perovskite decomposition. Additionally, the coordination of the polymer results in a heightened binding energy of Pb, leading to stronger halide ion binding and subsequent inhibition of halide ion migration. As a result, we demonstrate highly thermal stability of the heterostructure. Furthermore, the heterostructure exhibits the biexciton luminescence behaviors without the high energy excitation light. These findings present an effective approach for fabricating robust 2D halide perovskite lateral heterostructures. This research contributes to the advancement of the field by providing a new concept for fabricating stable 2D halide perovskite lateral heterostructures, and by offering significant insights into anionic behavior within such heterostructures.

Molecular ferroelectrics, characterized by outstanding photoelectric and unique ferroelectric properties, invigorate the field of ferroelectric photovoltaics. Nonetheless, the performance of molecular ferroelectric devices is hindered by fine grains resulting from poor high-temperature stability. In this work, we successfully achieved micron-grained molecular ferroelectric films by using the space-confined vapor deposited method. The optimized film exhibited a significant increase in grain size from the nanometer level (0.08 µm) to the micrometer level (~ 2 µm), leading to improved optoelectronic and ferroelectricity. Furthermore, it optimizes the energy level and enhances the photovoltaic performance of vertical devices. Research on the mechanism shows that high annealing temperature and inhibiting component loss play an important role in obtaining large grain films. This work provides new research ideas for improving the quality of molecular ferroelectric films and provides valuable reference for the fabrication of high performance molecular ferroelectric photovoltaic devices.