Highly loaded Prussian blue mixed matrix membrane for salt-tolerant solar catalytic oxidation

Abstract

Dispersing metal-organic framework (MOF) fillers within matrix polymeric membranes is essential for enhancing their availability, processability, and performance, yet hampered by serious agglomeration. Herein, we synthesize a novel Prussian Blue mixed matrix membrane for solar catalytic oxidation. Micro-scaled Prussian Blue microspheres are coated with Polyvinyl pyrrolidone-Vinyltriethoxysilane (PVP-VTES) crosslinked network to enhance the dispersed stability in the organic solution. The loading of modified Prussian Blue (mPB) fillers in Polyvinylidene fluoride (PVDF) matrix membrane could reach 40 %. The PB mixed matrix membrane shows enhanced hydrophilicity, water permeance, and excellent photothermal conversion capability. The membrane exhibits a sustainable tetracycline (TC) removal (>96 %) under solar irradiation in the presence of high salinity (e.g. NaCl, NaAC, and NaHCO₃). The photothermal effect facilitates peroxymonosulfate activation for reactive oxygen species efficient generation (¹O₂/•OH/SO₄^•-), resulting in instantaneous catalytic removal rate, multi-salt tolerance, and sustainable pollutants removal. The reported technique could potentially address interface challenges in mixed matrix membranes and can be extrapolated to the development of other fillers, achieving superior performance in membranes for water remediation.