Electro‐Conductive Silver‐Coated Polyamide‐Imide Membranes for Sustainable Water Treatment

Abstract This study focuses on developing and evaluating electro‐conductive polyamide‐imide (PAI) ultrafiltration membranes with a stable metallic coating that can tackle the dual challenges of dye removal and membrane fouling in wastewater treatment applications. The Ag‐coated PAI membranes exhibit high electrical conductivity (exceeding 5.6 × 10 ⁴ S cm ⁻¹ ), enabling the use of an applied electric potential to enhance dye removal efficiency and mitigate membrane fouling via electrochemical mechanisms. The electrochemical impedance spectroscopy (EIS) test confirm the high conductivity of the membranes. Meanwhile, linear sweep voltammetry (LSV) revealed the presence of the oxygen reduction reaction (ORR) and the hydrogen evolution reaction (HER) on the membrane surface. These findings provide valuable insights into the electrochemical potential for fabricating electro‐conductive membranes (ECMs). The Ag‐PAI membranes demonstrate remarkable dye rejection, with rates reaching 97% for reactive red 120 (RR120) and 90% for reactive black (RB) at an applied voltage of 7 V, while maintaining a consistent permeate flux of ≈100 LMH. The membranes also show significantly improved resistance to organic fouling, with the flux recovery ratio (FRR) increasing from 49.14% for pristine PAI to 80.41%, representing a 31% enhancement. The enhanced antifouling performance is attributed to gas bubble formation during voltage application, which disrupted the accumulation of the fouling cake layer. Together, these mechanisms effectively enhance the overall performance of the membrane.