Will organic–inorganic hybrid halide lead perovskites be eliminated from optoelectronic applications?

In the development of perovskite solar cells, a new version of Don Quixote is needed if scientists are to keep on seeking the most celebrated works of literature, according to the evaluation criterion of ‘THE FIRST’ and ‘THE BEST’. Perovskite solar cells have developed rapidly in recent years due to several factors, including their high light absorption capability, long carrier lifetime, high defect tolerance, and adjustable band gap. Since they were first reported in 2009, solar cells based on organic–inorganic hybrid halide lead perovskites have achieved a power conversion efficiency of over 23%. However, although there are broad development prospects for perovskite solar cells, their lead toxicity and instability resulting from the use of organic–inorganic hybrid halide lead perovskites such as CH(3)NH(3)PbI(3) limit their application, which is further deteriorating progressively. Therefore, the development of environmentally friendly, stable and efficient perovskite materials for future optoelectronic applications has long-term practical significance, which can eventually be commercialized. In this case, the discovery and development of inorganic lead-free perovskite light absorbing materials have become an active research topic in the field of photovoltaics. In this review, we discuss the application of organic–inorganic hybrid halide lead perovskites. This application is further analyzed and summarized using the research progress on inorganic lead-free perovskite solar cells by restoring some relevant prospects for the development of inorganic lead-free perovskite solar cells.