Environmentally Friendly Recovery of Silver from c-Si Solar Cell

Abstract

In this study, a solution capable of leaching silver (Ag) from solar cells in an environmentfriendly manner was presented, and a leaching effect according to the concentration was evaluated. Generally, a nitric acid (HNO 3 ) solution is used to leach Ag. However, it often causes environmental pollution owing to its high toxicity and the nitrous oxide (NOx gas) generated during the process, thus requiring considerable development. Accordingly, Ag leaching behavior according to the concentration was confirmed by mixing sulfuric acid (H 2 SO 4 ) and hydrogen peroxide (H 2 O 2 ) solutions. After this process, the optimal concentration condition was derived by confirming the Ag leaching effect through inductively coupled plasma-atomic emission spectroscopy (ICP-AES) analyses of the leachate. Additionally, Ag removal in the recovered scrap to which the optimal concentration condition was applied was confirmed using scanning electron microscopy (SEM)/energy-dispersive X-ray spectroscopy (EDS). Conclusively, as the H 2 SO 4 and H 2 O 2 mixed solution concentration increased, the Ag leaching effect tended to increase, and the optimal condition derived from the analysis reached a level capable of replacing the HNO 3 solution.