Idrees Sufyana, Sabah Aneeqa, Nazir Mohsin, Shahzad Whied Ul Hussan, Sabir Aneela
Department of Physics, Lahore College for Women University, Lahore 5200, Pakistan.
Department of Software Engineering, Lahore College for Women University, Lahore 5200, Pakistan.
ACS Omega. 2025 Jul 2;10(27):29768-29780. doi: 10.1021/acsomega.5c04165. eCollection 2025 Jul 15.
In this work, magnesium (Mg)-doped silica membranes were fabricated via a facile sol-gel method and systematically evaluated for multifunctional water purification applications with a specific focus on membrane distillation (MD). In this study, controlled incorporation of magnesium into the silica network effectively improves the membrane's hydrophobicity, structural compactness, and functional performance. This enhancement presents a novel and efficient strategy for developing high-performance membranes tailored to water desalination applications. Characterization using FTIR and SEM confirmed successful integration of Mg and trimethoxy-octyl-silane (CTMOS) into the silica matrix, leading to the formation of a dense, uniform surface with tunable hydrophobicity. Water contact angle measurements revealed superhydrophobic behavior at higher Mg loadings, ranging from 80° to 140°, indicating reduced wettability and improved liquid entry pressure. DCMD experiments using NaCl and NaSO solutions (1000 ppm) showed significant enhancement in salt rejectionup to 98.3%and a stable permeate flux of 32 L/m·h, especially for membranes doped with 15 wt % Mg. These improvements are attributed to densification and surface modification induced by Mg cross-linking, which inhibited pore wetting and maintained membrane stability during long-term operation. EDX and XRD confirmed elemental distribution and the amorphous structure of the membranes, respectively. Furthermore, density functional theory (DFT) simulations provided insight into the role of Mg in improving electronic structure, ion repulsion, and mechanical robustness at the molecular level. The membranes also exhibited strong antibacterial efficacy against and , suppressing over 90% bacterial regrowth. This multi-functionality, combining desalination efficiency, antifouling resistance, and antimicrobial activity, makes Mg-doped silica membranes a promising and scalable solution for sustainable water treatment, including high-salinity brines and industrial effluents.
在本工作中，通过简便的溶胶 - 凝胶法制备了镁（Mg）掺杂的二氧化硅膜，并对其进行了系统评估，以用于多功能水净化应用，特别关注膜蒸馏（MD）。在本研究中，将镁可控地掺入二氧化硅网络有效地改善了膜的疏水性、结构致密性和功能性能。这种增强为开发适用于海水淡化应用的高性能膜提供了一种新颖且高效的策略。使用傅里叶变换红外光谱（FTIR）和扫描电子显微镜（SEM）进行的表征证实了Mg和三甲氧基辛基硅烷（CTMOS）成功整合到二氧化硅基质中，从而形成了具有可调疏水性的致密、均匀表面。水接触角测量表明，在较高的Mg负载量下，水接触角范围为80°至140°，呈现超疏水行为，表明润湿性降低且液体进入压力提高。使用NaCl和NaSO溶液（1000 ppm）进行的直接接触式膜蒸馏（DCMD）实验表明，脱盐率显著提高——高达98.3%——并且渗透通量稳定在32 L/m²·h，特别是对于掺杂15 wt% Mg的膜。这些改进归因于Mg交联引起的致密化和表面改性，这抑制了孔的润湿并在长期运行期间保持了膜的稳定性。能量色散X射线光谱（EDX）和X射线衍射（XRD）分别证实了膜的元素分布和非晶结构。此外，密度泛函理论（DFT）模拟在分子水平上深入了解了Mg在改善电子结构、离子排斥和机械强度方面的作用。这些膜还对大肠杆菌和金黄色葡萄球菌表现出强大的抗菌功效，抑制了超过90%的细菌再生。这种结合了脱盐效率、抗污染性和抗菌活性的多功能性，使Mg掺杂的二氧化硅膜成为包括高盐度盐水和工业废水在内的可持续水处理的一种有前景且可扩展的解决方案。
