Direct Recycling of Silver and Silicon from Solar Cells through Selective Alkaline Etching

作者：Haochen Wang, Shiyu Wang, Shuaibo Gao, Fangzhao Pang, Hongya Wang, Xiang Chen, Shun Dai, Simin Xu, Yongxin Wu, Dihua Wang, Huayi Yin · 发表于：ACS Sustainable Chemistry & Engineering · 年份：2025 · DOI：10.1021/acssuschemeng.5c05190 · 被引用次数：6 · 研究领域：Photovoltaic Systems and Sustainability、Silicon and Solar Cell Technologies、Advancements in Battery Materials

Recycling retired silicon solar cells is indispensable to sustain the ever-increasing deployment of photovoltaic (PV) panels. However, the recycling of silver (Ag) and silicon (Si) remains a challenge because the use of toxic acids (e.g., HF, HNO 3 ) results in serious environmental burdens. Herein, we report a selective alkaline etching approach for the separation of Ag from Si solar cells, achieving complete separation in 5 min. The separation of Ag and Si is realized by the selective etching of SiO 2 and Si at the Ag/Si interface in the NaOH solution, where Ag is insoluble and collected as Ag wires. The recovery rates of Ag and Si reach 99% and 95%, respectively. Unlike traditional methods, Ag is directly recovered without the complex dissolution-electrolysis process. Si is recovered rather than fully or partially dissolved in the hydro-metallurgical process or converted into slags in the pyro-metallurgical process. Life Cycle Assessment (LCA) and Life Cycle Cost (LCC) results show that this approach has environmental and economic benefits. Overall, the selective alkaline etching approach is a green and low-cost recovery method to recycle Ag and Si, which will close the materials circle for the PV industry.