Abstract Sustainable and economic separation of Cu and Ni from their leaching solutions is a long-standing challenge. Here, the electrolysis of synthetic Cu Ni leaching solutions is examined using graphite electrodes in order to continuous separation of these metals, and also the preparation of photoactive graphene oxide (GO)-Cu2O/Cu hybrid structures. The carbon materials produced were characterized by various techniques including X-ray diffraction, Raman, Fourier-transform infrared and ultraviolet–visible spectroscopy, as well as electron microscopy. The proposed electrochemical approach is based on the surface exfoliation of the graphite anode to form GO, and the copper deposition on the cathode, followed by the chemical formation of Cu2O anchored on the surface of GO flakes. The concentration of Cu2+ in the solution is found to gradually reduce from an initial value of 2.79 to 0.37 g/l during 5 h of electrolysis, while the Ni2+ concentration remains almost unchanged. Moreover, the hybrid structure produced is found to be effective for the degradation of methyl orange under natural indoor weak light irradiation, with high cycling stability. The mechanism involved in the process is discussed.

中文翻译：

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石墨电极电化学处理Cu-Ni浸出液制备光活性氧化石墨烯-Cu2O/Cu纳米结构

摘要 从浸出液中可持续、经济地分离铜和镍是一项长期存在的挑战。在这里，为了连续分离这些金属，以及光活性氧化石墨烯 (GO)-Cu2O/Cu 混合结构的制备，使用石墨电极检查合成铜镍浸出液的电解。生产的碳材料通过各种技术进行表征，包括 X 射线衍射、拉曼、傅里叶变换红外和紫外-可见光谱以及电子显微镜。所提出的电化学方法基于石墨阳极表面剥离形成 GO，铜沉积在阴极上，然后化学形成固定在 GO 薄片表面上的 Cu2O。发现溶液中 Cu2+ 的浓度在电解 5 小时期间从初始值 2.79 逐渐降低到 0.37 g/l，而 Ni2+ 浓度几乎保持不变。此外，发现所产生的杂化结构在自然室内弱光照射下可有效降解甲基橙，具有高循环稳定性。讨论了该过程中涉及的机制。