Recent developments of electrodeposition-redox replacement in metal recovery and functional materials: A review

One way to overcome the complex problem of the increasing demand for metals coupled with the rapid depletion of high-grade raw materials is to boost research into innovative methods of metal recovery. Electrochemical recovery for metal production has already gained ground in the electrowinning and electrorefining of Cu, Zn, and Au, for example, from highly concentrated and purified hydrometallurgical solutions. Since 2015, an electrochemical technique, based on the combination of the electrodeposition (ED) and redox replacement (RR) processes, has been developed in the context of trace metal recovery (μg/L – mg/L). Specifically, EDRR enables the efficient recovery of precious metals, including Ag, Au, Pt, and Te, from underutilized secondary raw materials-hydrometallurgical solutions, where these metal species are naturally present. With highly flexible electrochemical process parameters, EDRR also allows controllable preparation of metal coatings, nanoparticles, and even functional surfaces directly from lower-grade resources, further indicating the promise of EDRR to relieve material scarcity. In this review, we analyze in detail the significant progress regarding EDRR for both metal recovery behavior and creation of high-value-added materials. The future prospects for EDRR, including energy efficiency and sustainable materials, are also outlined.