Sustainable development of perovskite solar cells: keeping a balance between toxicity and efficiency

Abstract

The term “sustainable solar cell” deals with human health and realizing the sustainable development of society. As a potential candidate, perovskite solar cells (PSCs) have been a hot topic for decades, recently achieving a power conversion efficiency (PCE) of over 25%. However, most of the raw materials used in the production of PSCs are on the list of hazardous substances by various environmental agencies. Although the chemical and physical strategies have initially attempted the pursuit of low-toxicity PSCs, the PCEs of these “green” PSCs are still much lower than that of their counterparts. Hence, identifying the trade-off between toxicity and efficiency has become prominent for the commercialization of PSCs. In this perspective, we first discuss the latest strategies for handling lead. Next, various solvents involved in the manufacturing of PSCs are reviewed and classified according to their sustainable potential. Finally, a comprehensive analysis of the perovskite cations and halogens is provided. Overall, we emphasize that the pursuit of a high PCE and low toxicity is driven by the development of commercial PSCs, where maintaining the balance between the two is vital in achieving genuinely green and sustainable PSCs.