Successful preparation of stable and efficient perovskite batteries

Recently, academician Huang Wei of the Chinese Academy of Sciences led the research team of Qin Tianshi and Wang Fangfang of Nanjing University of Technology to design and synthesize a new type of additive that can induce perovskite films to form more orderly crystals, thereby obtaining perovskite solar energy with a photoelectric conversion efficiency of 24.1%. Battery.

At present, perovskite solar cells have become the most powerful competitor in the field of new photovoltaics, but commercialization still faces stability problems such as humidity, heat, and light. Studies have shown that mixed ion perovskite will undergo phase segregation under continuous illumination, and the volatile cationic components will cause the formation of pinholes and residual lead iodide in the perovskite film, affecting the device performance under high temperature or humid conditions.

Wang Fangfang said that they used a variety of in-situ characterization techniques to monitor and conduct in-depth research on the interphase, nucleation and crystallization processes of perovskite films during spin coating and annealing processes, and found the root cause of the dilemma of mixed ion perovskites It is due to the multiple nucleation pathways induced by the mesophase that it cannot grow into a uniform and highly crystalline film. In response to the above problems, the research team designed and synthesized a multifunctional fluorine-substituted molecule as an additive. The additive can inhibit the formation of multiple intermediate phases, promote directional crystallization, and induce the perovskite film to form more ordered crystallization, thereby obtaining efficient and stable perovskite solar cell device performance.