Assessing the Environmental Impact of Pnictogen‐based Perovskite‐Inspired Materials for Indoor Photovoltaics

Abstract The development of eco‐friendly indoor photovoltaics (IPVs) for Internet‐of‐Things (IoT) devices is booming. Emerging IPVs, especially those based on lead halide perovskites (LHPs), outperform the industry standard of amorphous hydrogenated silicon (a‐Si:H). However, the toxic lead in LHPs drives the search for safer alternatives. Perovskite‐inspired materials (PIMs) containing bismuth (Bi) and antimony (Sb) have shown promise, achieving indoor power conversion efficiencies (PCE) approaching 10% despite early research stages. This is promising due to their eco‐friendlier light‐harvesting layers compared to LHPs. Yet, the environmental footprint of pnictogen‐based PIM over their lifecycle remains unassessed. This study conducts a life‐cycle assessment (LCA) of the best‐performing Sb‐ and Bi‐PIMs, considering PCE, raw material availability, energy consumption, and waste generation. It is find that PCE plays a decisive role in identifying the PIM for IPVs with minimized environmental impact, namely a Bi‐Sb alloy. Extended LCA simulations for industrial‐scale processing show that the most promising Bi‐PIM has a reduced environmental burden compared to a‐Si:H. It is also explore challenges and solutions for enhancing Bi‐and Sb‐PIMs’ sustainability. Overall, this study provides the first evidence of the potential of pnictogen‐based PIMs as a sustainable IPV technology, addressing whether lead‐free PIMs are truly eco‐friendly, thus contributing toward battery‐less IoT applications.