Recent advances in cross-linkable organic hole-transporting materials for perovskite optoelectronics

Metal halide perovskites have emerged as promising semiconductors for next-generation optoelectronics, particularly due to their solution processability and exceptional semiconductor properties. Over the past few decades, the performance of perovskite-based solar cells (PSCs) and light-emitting diodes (PeLEDs) has seen rapid improvements. However, the operational stability of these perovskite optoelectronic devices remains a significant challenge. One critical factor influencing both efficiency and stability is the choice of hole-transporting materials (HTMs). Recently, there has been a growing focus on cross-linkable HTMs as a means to enhance device stability. This review systematically summarizes the role of cross-linkable HTMs in PSCs and PeLEDs, emphasizing their material advantages, design principles, physical properties, and advancements in device performance. Special attention is given to the impact of cross-linkable HTMs on device interfaces and overall stability. We conclude by discussing the future challenges that must be addressed to further advance the application of cross-linkable HTMs in both PSCs and PeLEDs.