Palladium Nanoparticle-Decorated Mesoporous Polydopamine/Bacterial Nanocellulose as a Catalytically Active Universal Dye Removal Ultrafiltration Membrane

Removal of organic pollutants from industrial wastewater is of significant importance in wastewater treatment. Here, we present a highly efficient composite membrane composed of bacterial nanocellulose (BNC) embedded with mesoporous polydopamine (mPDA) and decorated with palladium (Pd) nanoparticles. The Pd-mPDA-BNC membrane is synthesized through simple and scalable process involving the in situ incorporation of mPDA nanoparticles into BNC matrix during its bacteria-mediated growth followed by in situ growth of Pd nanoparticles. The Pd-mPDA-BNC membrane exhibited high efficiency (above 99%) in removing cationic, anionic, and neutral dyes over a wide range of concentrations, and pH, and over multiple cycles of reuse. The synergistic effect of adsorption on mPDA nanoparticles and catalytic degradation by Pd nanoparticles enabled the simultaneous removal of multiple contaminants through a simple membrane filtration process. Furthermore, the Pd-mPDA-BNC membranes exhibited significantly higher water flux compared to commercially available ultrafiltration membranes with the same range of pore size, making them highly attractive for wastewater treatment.