Water Purification Performance of Composite Nanofiltration Membranes Loaded With Mesoporous Silica Nanospheres

ABSTRACT Nanofiltration (NF) membrane technology is pivotal to water‐scarcity‐addressing efforts. However, conventional thin‐film composite (TFC) membranes, limited by their inherent permeability–selectivity trade‐off, are incapable of simultaneously achieving a high water flux (WF) and good solute rejection efficiency. In this study, via interfacial polymerization (IP), a polyamide (PA)‐based selective layer (PSL) was prepared using aqueous‐phase monomer piperazine (PIP) and organic‐phase monomer trimesoyl chloride (TMC), and then mesoporous silica nanospheres (MSNs) were embedded in this layer, forming high‐performance thin‐film nanocomposite (TFN) membranes. MSN incorporation enhanced membrane surface roughness and hydrophilicity while creating new water transport channels, thus improving membrane permeability. Additionally, the hydroxyl‐rich MSN surface facilitated a higher crosslinking degree during IP, resulting in a thinner PSL. As a result, TFN‐25, which was the TFN membrane with the optimal formulation, demonstrated an exceptional Na 2 SO 4 rejection efficiency (95.3%) and significantly enhanced WF (13.4 L·m −2 ·h −1 ·bar −1 ), outperforming TFC.