Electroless Ni-Sn-P plating to fabricate nickel alloy coated polypropylene membrane with enhanced performance

Surface metallization of membrane via electroless plating for improvement of permeation flux and anti-fouling performance has attracted extensive attentions in recent years. However, high activation cost and poor stability have always been the obstacles to its practical application. It is urgently desired to explore economical and stable membrane modification methods. Herein, a novel strategy for fabrication of a hydrophilic and conductive separation membrane with low cost, excellent filtration performance, and high chemical stability was ingeniously proposed. A nickel-tin/cobalt-polypyrrole (NiSn/Co-PPy) coating was deposited onto the PP membrane through successive three-step route including in-situ vapor-phase polymerization, cobalt activation and electroless plating. The successful formation of NiSn/Co-PPy coating on membrane surface was confirmed by a series of characterizations. Driven by self-gravity, the optimum modified membrane (NiSn4-15/Co-PPy) applied with an external electric field (9.0 V) had prominent permeation flux (189 L m(-2) h(-)(1)), impressive separation efficiency (100%) and outstanding cycle stability for separation of n-hexane/water emulsion. Under the micro-electric field (2.0 V), the average flux of the NiSn4-15/Co-PPy membrane for yeast suspension filtration reached 22.3 L m(-2) h(-)(1), which is approximately 3 and 9 times higher than that of the modified membrane without electric field and the original membrane, respectively. Meanwhile, the external electric field also endowed the NiSn4-15/Co-PPy membrane with a maximum flux recovery rate of 82.7%. In addition, the modified membrane was confirmed to have brilliant stability and acid resistance. This study provided a new strategy and novel insights into fabrication of composite hydrophilic conductive membrane for water treatment.

Automated summary

A novel strategy was proposed for fabrication of a hydrophilic and conductive separation membrane with low cost, excellent filtration performance, and high chemical stability. The modified membrane showed outstanding separation efficiency, permeation flux, and cycle stability, especially when applied with an external electric field. External electric field significantly enhanced the filtration performance of the membrane, demonstrating improved flux recovery rate and stability.