For achieving high‐performance p‐i‐n perovskite solar cells (PSCs), hole transporting materials (HTMs) are critical to device functionality and represent a major bottleneck to further enhancing device stability and efficiency in the inverted devices. Three dopant‐free polymeric HTMs are developed based on different linkage sites of triphenylamine and phenylenevinylene repeating units in their main backbone structures. The backbone curvatures of the polymeric HTMs affect the morphology and hole mobility of the polymers and further change the crystallinity of perovskite films. By using PTA‐mPV with moderate molecular curvature, p‐i‐n PSCs with high efficiency of 19.5% and long‐term stability can be achieved. The better performance is attributed to the more effective hole extraction ability, higher charge‐carrier mobility, and lower interfacial charge recombination. Furthermore, these three polymeric HTMs are synthesized without any noble metal catalyst, and show great advantages in future application owing to the low‐cost.

To date, numbers of polymeric hole-transporting materials (HTMs) have been developed to improve interfacial charge transport to achieve high-performance inverted perovskite solar cells (PSCs). However, molecular design for passivating the underlying surface defects between perovskite and HTMs is a neglected issue, which is a major bottleneck to further enhance the performance of the inverted devices. Herein, we design and synthesize a new polymeric HTM PsTA-mPV with the methylthiol group, in which a lone pair of electrons of sulfur atoms can passivate the underlying interface defects of the perovskite more efficiently by coordinating Pb 2+ vacancies. Furthermore, PsTA-mPV exhibits a deeper highest occupied molecular orbital (HOMO) level aligned with perovskite due to the π-acceptor capability of sulfur, which improves interfacial charge transfer between perovskite and the HTM layer. Using PsTA-mPV as a dopant-free HTM, the inverted PSCs show 20.2% efficiency and long-term stability, which is ascribed to surface defect passivation, well energy-level matching with perovskite, and efficient charge extraction.

AC-driven EL devices have always been the focus of attention because of their great value in the field of intelligent lighting and multifunctional display. AC-driven EL devices based on various materials and optimization methods have been continuously developed. However, the important luminescent semiconductor materials have rarely been systematically studied. Herein, the development of efficient and stable organic and perovskite EL devices, including the optimization of light-emitting materials, and the device structures are comprehensively studied. The different frequency-dependent characteristics of AC-driven EL devices based on organic semiconductors and perovskite semiconductors are mainly introduced due to the discrepancy in the characteristics of the materials themselves. In addition, approaches to reduce the driving voltage and enhance the luminescence performance of AC-driven organic EL devices are also presented. For AC-driven perovskite EL devices, the bias voltage with frequent switching of the electric field direction can alleviate the thermal degradation and charge accumulation of the material to improve the stability of the devices and also effectively suppress the phenomenon of ion migration. The unique advantages of the AC driving mode in the realization of color tunable EL devices are revealed. The application potential and challenges of AC-driven EL devices are discussed.