Recycling spent lead-acid batteries into lead halide for resource purification and multifunctional perovskite diodes

Lead-acid batteries are a reliable and cost-effective uninterrupted power supply for cars, wheelchairs, and others. Recycling the spent lead-acid batteries has increased cost and could be a serious pollution issue after extensive use. It is important to exploit new-generation application to increase their value. In this article, we used a simple method for recycling spent lead-acid batteries for a useful lead iodide resource with a high purity of over 99% and a recycling yield of 93.1% and then fabricated multifunctional FAPbI₃ perovskite diodes using recycled lead iodide (PbI₂). The cost of recycled PbI₂ based on lab-grade chemicals is estimated to be only 13.6% that of lab-grade PbI₂, which undoubtedly greatly reduces the preparation cost of devices in the lab. The external quantum efficiencies of our perovskite diodes prepared with commercial and recycled PbI₂ are 19.0 and 18.7%, respectively, which shows that the performance of the device prepared from recycled PbI₂ is comparable to that of commercial lab-grade PbI₂. Based on the expense of industrial-grade chemicals, the cost of recycled PbI₂ is extrapolated to be 70.2% that of industrial-grade PbI₂. Therefore, it can not only offer an approach to recycle hazardous solid waste but also save manufacturing cost of new-generation photoelectric devices, leading to earning additional value for lead waste.