Abstract Metal and nitrogen-doped carbon (M-N-C) materials have been considered as the most promising non-precious metal oxygen reduction (ORR) catalysts to replace expensive Pt catalysts. Due to high Fenton catalytic activity of Fe element and the resulting instability, Co-based N–C (Co–N–C) catalysts without Fenton catalytic activity should be a worthier ORR catalyst being explored. Although the high ORR activity of Co–N–C catalyst has been demonstrated in aqueous half-cell tests, their performance under PEMFC working condition is still far away from that of state-of-the-art Fe–N–C catalysts. In this study, a high-performance Co–N–C catalyst was synthesized by one-step pyrolyzing Co-doped ZIF-8 (zeolitic imidazolate framework-8) particles in-situ grown on the high-surface-area KJ600 carbon black with high electronic conductivity. The resulting Co–N–C catalyst exhibited high intrinsic ORR activity, fast mass transfer rate and high electronic conductivity, and thus yielded a remarkable peak power density of 0.92 W cm-2 in H2–O2 PEMFC, which is comparable to state-of-the-art Fe–N–C catalyst. This strategy is helpful to synthesize highly active M-N-C ORR catalysts with improved mass transfer and electric conductivity.

中文翻译：

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ZIF 衍生的 Co-N-C ORR 催化剂在质子交换膜燃料电池中具有高性能

摘要 金属和氮掺杂的碳 (MNC) 材料被认为是最有前途的非贵金属氧还原 (ORR) 催化剂，以取代昂贵的 Pt 催化剂。由于Fe元素的高芬顿催化活性和由此产生的不稳定性，没有芬顿催化活性的Co基N-C（Co-N-C）催化剂应该是一种值得探索的ORR催化剂。尽管 Co-N-C 催化剂的高 ORR 活性已在水性半电池测试中得到证明，但它们在 PEMFC 工作条件下的性能仍与最先进的 Fe-N-C 催化剂相距甚远。在这项研究中，通过一步热解 Co 掺杂的 ZIF-8（沸石咪唑酯骨架-8）颗粒在高表面积 KJ600 炭黑上原位生长，合成了一种高性能 Co-N-C 催化剂。高电子导电性。所得的 Co-N-C 催化剂表现出高固有 ORR 活性、快速传质速率和高电子电导率，因此在 H2-O2 PEMFC 中产生了 0.92 W cm-2 的显着峰值功率密度，与状态相当-最先进的Fe-N-C催化剂。该策略有助于合成具有改善的传质和导电性的高活性 MNC ORR 催化剂。