Recently, perovskites have garnered great attention owing to their outstanding characteristics, such as tunable bandgap, rapid absorption reaction, low cost and solution-based processing, leading to the development of high-quality and low-cost photovoltaic devices. However, the key challenges, such as stability, large-area processing, and toxicity, hinder the commercialization of perovskite solar cells (PSCs). In recent years, several studies have been carried out to overcome these issues and realize the commercialization of PSCs. Herein, the stability and photovoltaic efficiency improvement strategies of perovskite solar cells are briefly summarized from several directions, such as precursor doping, selection of hole/electron transport layer, tandem solar cell structure, and graphene-based PSCs. According to reference and analysis, we present our perspective on the future research directions and challenges of PSCs.

Graphene quantum dot (GQD)/Co(OH) ₂ composite based wire-shaped, quasi-solid-state hybrid supercapacitor device exhibits enhanced specific capacitance, a high capacitance retention rate and superior device stability.

In this work, the resistive memory devices were fabricated based on all-inorganic CsPbBr ₃ nanocrystals (NCs) embedded into the insulating polymethylmethacrylate (PMMA) with a configuration of Au/PMMA/PMMA: CsPbBr ₃ NCs/PMMA/indium tin oxide (ITO). The as-fabricated devices exhibit forming-free bipolar resistive switching with resistance ratio of HRS to LRS ( R _{H / L} ) evolving from metastable 10 ⁶ to stable 10. In HRS with high R _{H / L} , the devices witness the prompt photoresponse under light illumination of 365 nm, 405 nm, 420 nm, and 500 nm. Also, set voltages of resistive switching with low R _{H / L} can be reduced by the illumination. Furthermore, the resistive switching and photoresponse of Au/PMMA/PMMA: CsPbBr ₃ NCs/PMMA/ITO devices were elucidated by considering the photosensitive property and role of trapping/de-trapping centers of CsPbBr ₃ NCs. This work suggests the tunable resistive switching of Au/PMMA/PMMA: CsPbBr ₃ NCs/PMMA/ITO devices through light illumination, and controllable photoresponse by resistive states.