Toward Eco-friendly and Stable Perovskite Materials for Photovoltaics

The discovery and development of new Pb-free perovskite light-absorber materials that are eco-friendly and stable has become an active research area in the field of photovoltaics (PVs). These perovskites are being considered for possibly replacing the Pb-based organic-inorganic halide perovskites in state-of-the-art perovskite solar cells. While the recent effort in this area has led to certain progress, some scientific and technological issues still remain unresolved. Here we provide perspectives on the comprehensive understanding of perovskite toxicity/instability, followed by design strategies for new nontoxic, stable perovskites. We also envision unprecedented challenges in the processing of the promising candidate perovskites that bridges materials design and actual devices. Future research in these directions will open up new possibilities in realizing eco-friendly and stable perovskite PVs for real-world applications. Solar power is the most abundant and free source of renewable and sustainable energy on Earth. In response to the pressing need to develop efficient, low-cost photovoltaics (PVs) to harness the solar power, perovskite solar cells (PSCs) have recently emerged as a potential distruptive PV technology. However, the state-of-the-art PSCs employ lead-based organic-inorganic halide perovskites as light absorbers, raising concerns regarding their chemical stability and the use of toxic element lead (Pb) that may be released into the environment. Therefore, it is of long-term practical importance to develop eco-friendly, stable, and efficient perovskite materials for future PSCs that can eventually be commercialized. Moreover, discovery and development of these new perovskite materials will have profound implications on a broad range of (opto)electronic applications, including, but not limited to, solar cells, light-emitting devices, lasers, photodetectors, and X-ray imaging. The discovery and development of efficient Pb-free perovskite light-absorber materials that are eco-friendly and stable has become an active research area in the field of photovoltaics (PVs). Here we provide perspectives on the comprehensive understanding of perovskite toxicity/instability, followed by design strategies for new Pb-free, stable perovskites. Future research in these directions will open up new possibilities in realizing eco-friendly, stable, and efficient perovskite PVs for real-world applications.