Efficient and durable composite membranes based on polydopamine-mediated sulfonated graphene oxide for direct methanol fuel cells
Efficient and durable composite membranes based on polydopamine-mediated sulfonated graphene oxide for direct methanol fuel cells
复制标题
用于直接甲醇燃料电池的基于聚多巴胺介导的磺化氧化石墨烯的高效耐用复合膜
DOI：
10.1039/d1ta07882h
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发表时间：
2021
影响因子：
11.9
通讯作者：
Lin Jun
中科院分区：
文献类型：
--
作者：
Liu Xin;Zhai Shaoxiong;Zhang Xiyuan;Mao Pengzhi;He Shaojian;Dai Wenxu;Lin Jun
磺化氧化石墨烯（SGO）已被用作直接甲醇燃料电池（dmfc）中质子交换膜（PEMs）的有效填料，以增强其性能。在此之前，SGO主要是通过基于氧化石墨烯（GO）的本征基团的功能化制备的，这可能导致不均匀性或磺化不足，并可能限制膜性能的提高。为了克服这一被广泛忽视的问题，本文通过在聚多巴胺（PDA）沉积的氧化石墨烯上进行磺化，制备了一种新型的氧化石墨烯磺化产物SDGO，与不含PDA的氧化石墨烯相比，SDGO的磺化均匀性得到了改善。因此，与不含pda的SGO相比，SDGO填充的磺化聚醚醚酮（SPEEK）复合PEMs具有更好的基质-填料相容性、更大的亲水结构域和更少的空隙，从而大大提高了质子电导率、甲醇屏障和力学性能。基于SPEEK-SDGO的DMFC在很大程度上优于基于Nafion 212的DMFC，输出功率达到177.93 mW cm - 2(80°C， 1 M甲醇/O2)，这是基于SGO复合膜的DMFC中最具竞争力的功率密度之一。此外，PDA的自由基清除能力提高了SPEEK-SDGO复合膜在化学加速应力测试中的稳定性。机械加速应力测试和恒压实验进一步证实了SPEEK-SDGO复合膜在DMFC操作过程中的优异耐久性。
Sulfonated graphene oxide (SGO) is already utilized as an effective filler in proton exchange membranes (PEMs) for performance enhancement in direct methanol fuel cells (DMFCs). Previously, SGO has been mostly prepared via functionalization based on the intrinsic groups of graphene oxide (GO), which may cause inhomogeneity/insufficient sulfonation and possibly limit the improvement of membrane performance. To overcome this widely overlooked problem, herein, a new type of GO sulfonation product, SDGO, is fabricated by carrying out the sulfonation on polydopamine (PDA) deposited GO, which results in improved uniformity/sufficient sulfonation on SDGO compared to PDA-free SGO. Therefore, the sulfonated poly(ether ether ketone) (SPEEK) composite PEMs filled with SDGO show better matrix–filler compatibility, larger hydrophilic domains and less voids than those using PDA-free SGO, which lead to much improved proton conductivity, methanol barrier and mechanical properties. SPEEK–SDGO based DMFCs largely outperform Nafion 212 based DMFCs, achieving an output of 177.93 mW cm−2 (80 °C, 1 M methanol/O2), one of the most competitive DMFC power densities reported for DMFCs based on SGO composite membranes. Moreover, the radical scavenging ability of PDA boosts the stability of SPEEK–SDGO composite membranes in chemical accelerated stress tests. Mechanical accelerated stress tests and constant voltage experiments further confirm the superior durability of SPEEK–SDGO composite membranes during DMFC operations.