Layered double hydroxide/boron nitride nanocomposite membranes for efficient separation and photodegradation of water-soluble dyes

Abstract

Widespread access to clean water is becoming increasingly scarce due to various factors, including increasing urbanisation and industrialisation, biodiversity loss, and climate change. The development of innovative and sustainable methods of water purification are urgently required. Herein, we report the development of new, high-performance nanofiltration (NF) membranes based on a recyclable CuAl–CO₃ LDH/BNOx nanocomposite. These membranes have demonstrated up to 100% retention of Evans blue, methyl orange, methylene blue and rhodamine B, and exceptional water flux. Furthermore, the presence of CuAl–CO₃ LDH induces up to 91% photodegradation of these dyes under visible light conditions in 120 minutes using a household LED lamp, acting as a potential low-cost, viable solution to membrane fouling. Importantly, this is the first report of Evans blue degradation by a visible-light active LDH photocatalyst. We believe that this work represents a significant step forward in advanced nanofiltration technology.