Abstract:
Inorganic CsPbX3 materials have been widely studied due to their excellent photoelectric properties, adjustable band gap and simple preparation process. However, the crystallization rate of CsPbX3 perovskite is too fast by solution-based method, which leads to poor film quality with many defects at the bulk and surface of the film, and affects the efficiency and stability of the CsPbX3 perovskite solar cells (PSCs). Therefore, the obtaining of high-quality CsPbX3 perovskite films is the key to achieving efficient and stable inorganic PSCs. In recent years, it has been proven that precursor engineering is an effective strategy for obtaining high quality perovskite films. Based on the overview of the crystal structure, photoelectric properties, preparation process and current problems of inorganic CsPbX3 perovskite films, this paper summarizes and discusses several methods of preparing high quality inorganic perovskite films based on precursor engineering, including precursor component optimization, additive strategy, intermediate phase adjusting and heterogeneous structure construction. The advantages of these method are summarized as follows: component optimization can effectively regulate the crystallization rate and path; additive strategy focuses on passivation of different types of defects; intermediate phase adjusting is the key factor to obtain excellent surface morphology and high crystallinity perovskite films; and heterogeneous structure construction is a promising strategy to inhibit adverse non-radiative recombination and improve the stability of perovskite. Finally, the development trend of CsPbX3 PSCs is prospected. In the future, the crystallization mechanism and defect passivation mechanism of CsPbX3 perovskite film should be further explored to prepare high-quality perovskite film. Meanwhile, the preparation and development of large-area devices and tandem cells should be investigated to achieve higher photoelectric conversion efficiency and commercial application.
