Polyhedral oligomeric silsesquioxane (POSS) has attracted increasing attention because of its organic/inorganic, nanosize, easily functional nature, especially in the applications of direct methanol fuel cells (DMFCs). In this work, we have successfully synthesized a novel bifunctional POSS (Vi-POSS-SO₃Na) with vinyl and sulfonic acid groups by thiol-ene click reaction. Vi-POSS-SO₃Na was introduced into Nafion® matrix and cross-linked by in-situ simply thermal treatment. The implantation of the bifunctional POSS filler gives significant improvements in the performance of such proton exchange membranes (PEMs). The cross-linked hybrid membrane with 12 wt% of Vi-POSS-SO₃Na (X-Nafion@POSS-12) has a high proton conductivity (121 mS cm⁻¹) at 80 °C, excellent dimensional stability and the lowest methanol permeability (5.4 × 10⁻⁸ cm² s⁻¹). The highest power density of the DMFCs was obtained by using the X-Nafion@POSS-12 as PEM in DMFC at 80 °C, and its value (34.93 mW cm⁻²) is twice higher than that of Nafion 212 membrane (14.90 mW cm⁻²). The novel in-situ fabrication method gives a simple and potential approach for the preparation of PEMs used in DMFCs.

多面体低聚倍半硅氧烷 (POSS) 因其有机/无机、纳米尺寸、易于功能的性质而受到越来越多的关注，特别是在直接甲醇燃料电池 (DMFC) 的应用中。在这项工作中，我们通过硫醇-烯点击反应成功地合成了一种具有乙烯基和磺酸基团的新型双功能 POSS ( Vi -POSS-SO ₃ Na)。Vi -POSS-SO ₃ Na 被引入到 Nafion® 基质中，并通过原位简单的热处理进行交联。双功能 POSS 填料的植入显着改善了这种质子交换膜 (PEM) 的性能。12 wt% Vi -POSS-SO ₃的交联杂化膜Na ( X -Nafion@POSS-12)在 80 °C 下具有高质子传导率 (121 mS cm ^-1 )、优异的尺寸稳定性和最低的甲醇渗透率 (5.4 × 10 ^-8 cm ² s ^-1 )。DMFCs的最高功率密度是在 80°C下使用X -Nafion@POSS-12 作为 DMFC 中的 PEM 获得的，其值 (34.93 mW cm ^-2 ) 是 Nafion 212 膜 (14.90 mW) 的两倍厘米^-2 )。新的原位制造方法为制备用于 DMFC 的 PEM 提供了一种简单且具有潜力的方法。