In direct methanol fuel cells (DMFC), methanol crossover is a major issue which has reduced the performance of polymer electrolyte membrane (PEM) for energy generation. In this study, graphene oxide (GO) and conductive polyaniline decorated GO (PANI-GO) were used as additives in fabrication of sulfonated poly(ether ether ketone) (SPEEK) nanocomposite PEM membrane to reduce methanol crossover. PANI-GO was synthesized by in situ polymerization method and the formation of PANI coated GO nanostructures was confirmed by surface morphology and crystallinity analysis. The membrane morphology and topography analysis confirmed that GO and PANI-GO were well dispersed on the surface of SPEEK membrane. 0.1 wt% PANI-GO modified SPEEK nanocomposite membrane exhibited the highest water uptake and ion exchange capacity of 40% and 1.74 meq g⁻¹, respectively. The oxidative stability of the nanocomposite membranes also improved. Lower methanol permeability of 4.33 × 10⁻⁷ cm⁻²S⁻¹ was noticed for 0.1 wt% PANI-GO modified SPEEK membrane. PANI-GO modified SPEEK membrane enhanced the proton conductivity, which was due to the existence of acidic and hydrophilic group present in PANI and GO. PANI-GO modified SPEEK membrane held higher selectivity of 1.94 × 10⁴ S cm⁻³ s⁻¹. Overall, these studies revealed that PANI-GO modified SPEEK membrane is a potential material for DMFC applications.

中文翻译：

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用于直接甲醇燃料电池应用的磺化聚（醚醚酮）膜上聚苯胺修饰的氧化石墨烯

在直接甲醇燃料电池 (DMFC) 中，甲醇渗透是降低聚合物电解质膜 (PEM) 发电性能的主要问题。在这项研究中，氧化石墨烯 (GO) 和导电聚苯胺修饰的 GO (PANI-GO) 被用作制造磺化聚醚醚酮 (SPEEK) 纳米复合 PEM 膜的添加剂，以减少甲醇交叉。PANI-GO是通过原位聚合法合成的，表面形貌和结晶度分析证实了PANI涂层GO纳米结构的形成。膜形态和形貌分析证实GO和PANI-GO很好地分散在SPEEK膜表面。0.1 wt% PANI-GO 改性 SPEEK 纳米复合膜表现出最高的吸水率和离子交换容量，分别为 40% 和 1.74 meq g^-1，分别。纳米复合膜的氧化稳定性也得到改善。对于 0.1 wt% PANI-GO 改性 SPEEK 膜，注意到4.33 × 10 ^-7 cm ^-2 S ^{-1 的}较低甲醇渗透率。PANI-GO 修饰的 SPEEK 膜增强了质子电导率，这是由于 PANI 和 GO 中存在酸性和亲水基团。PANI-GO 改性SPEEK 膜具有更高的选择性，为1.94 × 10 ⁴ S cm ^-3  s ^-1。总的来说，这些研究表明，PANI-GO 改性 SPEEK 膜是 DMFC 应用的潜在材料。