Mining diverse resources from electroplating wastewater are critical for maximizing wastewater economic value and minimizing adverse environmental impacts. We have demonstrated an autonomous electrochemical-osmotic system (EOS), which can simultaneously recover copper metals, water, and electric energy from electroplating wastewater. In this study, we enhanced water production, electricity generation, and metal recovery of the EOS using polyelectrolyte multilayer nanofiltration (PMNF) membranes instead of the forward osmosis membranes. The PMNF membrane is fabricated by alternately depositing two oppositely charged polymers, poly(diallyldimethylammonium chloride) (PDADMAC, (+)) and poly(sodium 4-styrenesulfonate) (PSS, (−)), on the nanofiltration (NF) membrane substrate. Results suggested that the water/salt selectivity of the PMNF membrane increase to 25.1 L mol⁻¹ with the increase of the number of the polyelectrolyte deposited layers to 6.0. The EOS assembled with a 1.5-layer PMNF membrane achieved a water production rate of 6.06 L m⁻² h⁻¹ and a maximum power density of 1.18 mW cm⁻² by treating synthetic electroplating wastewater, 2.63 and 1.21 times higher than conventional EOS (i.e., FO membrane), respectively. Further, we clarified that the PMNF-EOS effectively inhibited the forward transport of various metal cations (e.g., Cu²⁺, Cr⁶⁺, Zn²⁺, and Ni²⁺) while also extracting freshwater, generating power, and recovering copper from electroplating wastewater. Our study provided a new avenue for developing a high-performance EOS to reclaim multiple resources from electroplating wastewater.

从电镀废水中挖掘各种资源对于最大限度地提高废水经济价值和减少不利的环境影响至关重要。我们已经展示了一种自主电化学渗透系统 (EOS)，它可以同时从电镀废水中回收铜金属、水和电能。在这项研究中，我们使用聚电解质多层纳滤 (PMNF) 膜而不是正向渗透膜来增强 EOS 的产水、发电和金属回收。PMNF 膜是通过在纳滤 (NF) 膜基材上交替沉积两种带相反电荷的聚合物聚（二烯丙基二甲基氯化铵）（PDADMAC，（+））和聚（4-苯乙烯磺酸钠）（PSS，（-））制成的。^-1随着聚电解质沉积层数增加到6.0。用1.5层PMNF膜组装的EOS通过处理合成电镀废水实现了6.06 L m ^-2 h ^{-1的产水率和1.18 mW cm -2}的最大功率密度，分别是传统EOS的2.63和1.21倍（即，FO 膜），分别。此外，我们阐明了 PMNF-EOS 有效地抑制了各种金属阳离子（例如，Cu ²⁺、Cr ⁶⁺、Zn ²⁺和 Ni ^{2+ ）的正向传输。}) 同时还提取淡水、发电和从电镀废水中回收铜。我们的研究为开发高性能 EOS 以从电镀废水中回收多种资源提供了新途径。