Near-complete Ag recovery from silicon solar cells via localized electrolyte-jet recycling

Current strategies for silver (Ag) recovery from photovoltaic waste are hampered by complex, costly, and poorly controlled process flows. In this study, we present a novel technology for the targeted separation of Ag from end-of-life silicon solar cells (EoL-SSCs) using a localized electrolyte jet (EJ) recycling system. Under low applied voltage (5 V) in a circulating dilute HNO₃ solution (12 wt%), 90.2 % of the surface-metallized Ag is selectively dissolved within 7 min, and near-complete separation (> 95 %) is achieved after 30 min of treatment. This custom-designed platform, featuring a unique vertical operation mode and configurable parameters (i.e., adjustable cathode geometry and tunable electrolyte flow rate), suppresses Al co-dissolution by >80 % compared with conventional acid leaching. The electric field intensified by the sharp tip effect drives the directional generation of high-valence Ag species, accelerating dissolution kinetics and delivering exceptional current efficiencies (removal: 87.4 %; recovery: 77 %). The resulting Ag⁺-rich electrolyte is directly utilized in a one-step reverse EJ deposition process to produce Ag coatings with high purity (96 %) and excellent conductivity (1.7×10⁻⁸ Ω·m). By integrating selective metal separation with electrochemical additive manufacturing, this strategy offers an economically viable and environmentally sustainable route for the valorization of critical metals from diverse e-waste streams.