Flexible metal membrane integrated electrified and catalytic attributes for multifunctional water purification with enhanced scaling resistance

Abstract

Electrified and ceramic membranes assembled with rigid materials have been greatly appreciated for unique electrical responsiveness and catalytic properties for efficient water purification. However, the intensive van der Waals forces of traditional rigid materials have historically resulted in poor rejection, scaling resistance and mechanical properties to those of standard filters. In response, an innovative fabrication approach has been formulated, entailing induced fit theory inspired activation of inert polyamide (PA) substrates, concomitantly coupled with the in-situ growth of CoOx nanoflowers on the polymer membrane surfaces. This method yielded activated terminal amide groups that enable specific coordination in a manner akin to that of a zymogen activation. The ensuing development of CoOx nanoflowers engendered a notably rugged interface, prompting the emergence of grass-like membrane structures reminiscent of the lotus effect. The integration of CoOx nanoflowers endowed the resultant membrane augmented surface hydrophilicity, elevated rejection efficiency, exceptional conductivity, and degradation potential. These effects synergistically yielded an exceptional water permeability for the fabricated membrane (1.90×103 L·m−2·h−1), surpassing that of the CoOx-free control membrane by over twofold, coupled with a separation rate exceeding 99.8 %. Furthermore, interface engineering contributed to an exceptionally high reaction rate constant of the resultant membrane (2.93), surpassing that of the inherent membrane by over 167-fold. Importantly, the self-cleaning prowess, facilitated by CoOx, was evidenced by the recoverability of severely fouled membranes through PMS rinsing and electrical interaction. The mechanisms underlying the membrane's multifaceted antifouling performance were systematically unveiled through the extended Derjaguin-Landau-Verwey-Overbeek theory. By employing the facile and ingenious induced fit theory, this approach ushers forth an extraordinary avenue for water purification and scaling resistance applications, distinctly accentuating the innovative essence of this study.