The production of freshwater by desalination has great significance. Membrane distillation (MD) is considered as a promising technique for desalination. As a popular candidate for MD desalination, FAS (fluoroalkylsilane)-modified ceramic membrane suffers from insufficient stability, such as membrane wetting and decline of salt rejection during long-term operation, because of the degradation of hydrophobicity. In the present work, a novel strategy is proposed to enhance the long-term desalination stability of FAS-modified cordierite ceramic membranes by constructing a porous SiO₂@PDMS (polydimethylsiloxane) protective layer on their tops to obtain a robust hydrophobic property. The results show that such a layer can be successfully fabricated by a two-step spraying method with hydrosoluble NaCl particles as templates. The incorporation of SiO₂ nanoparticles into PDMS generates a loose and porous structure in the layer and renders an enhanced hydrophobicity. At a SiO₂/PDMS mass ratio of 0.30, the membranes exhibit a notable resistance to both mechanical abrasion and chemical corrosion. The dissolution of NaCl templates leaves behind cavities within the layer, which prevents the SiO₂/PDMS species from blocking the membrane pores and thereby helps to reduce the vapor transport resistance. These membranes are highly stable upon long-term desalination (>300 h) and can preserve a stable water flux of 8.10 kg/m²h and a salt rejection close to 100% under the following conditions: a feed temperature of 80°C, a NaCl concentration of 3.5 wt% and a feed flow rate of 300 mL/min. The SiO₂@PDMS layer is responsible for the outstanding desalination stability since it prevents membrane wetting by reducing the direct contact of the reflux feed solution to the underlying cordierite ceramic membranes.

海水淡化生产淡水意义重大。膜蒸馏（MD）被认为是一种很有前途的海水淡化技术。作为MD脱盐的热门候选者，FAS（氟烷基硅烷）改性陶瓷膜由于疏水性降低而存在稳定性不足，例如膜润湿和长期运行期间脱盐率下降等问题。_{在目前的工作中，提出了一种新的策略，通过构建多孔 SiO 2}来提高 FAS 改性堇青石陶瓷膜的长期脱盐稳定性。@PDMS（聚二甲基硅氧烷）保护层在其顶部获得强大的疏水性能。结果表明，以水溶性NaCl颗粒为模板，采用两步喷涂法可以成功制备出这种层。将 SiO ₂纳米颗粒掺入 PDMS 中会在层中产生松散的多孔结构，并增强疏水性。在 0.30 的 SiO ₂ /PDMS 质量比下，膜对机械磨损和化学腐蚀都表现出显着的抵抗力。NaCl 模板的溶解会在层内留下空洞，从而阻止 SiO ₂/PDMS 物质不会阻塞膜孔，从而有助于降低蒸汽传输阻力。这些膜在长期脱盐 (>300 h) 后高度稳定，在以下条件下可保持 8.10 kg/m ² h 的稳定水通量和接近 100% 的脱盐率：进水温度为 80°C， NaCl 浓度为 3.5 wt%，进料流速为 300 mL/min。SiO ₂ @PDMS 层负责出色的脱盐稳定性，因为它通过减少回流进料溶液与下方堇青石陶瓷膜的直接接触来防止膜润湿。