Defective porous carbon microrods derived from fullerenes (C<sub>70</sub>) as high-performance electrocatalysts for the oxygen reduction reaction
Defective porous carbon microrods derived from fullerenes (C<sub>70</sub>) as high-performance electrocatalysts for the oxygen reduction reaction
复制标题
源自富勒烯（C<sub>70</sub>）的缺陷多孔碳微棒作为氧还原反应的高性能电催化剂
作者：
He Zhimin;Wei Peng;Xu Ting;Guo Ziqian;Han Jiantao;Akasaka Takeshi;Guo Kun;Lu Xing
破坏 sp2-碳骨架的完整性提供了一种为氧还原反应 (ORR) 创建活性位点的有效策略。在这项工作中，富勒烯（C70）分子由12个五边形和25个六边形组成，全部由sp2-C原子键合，在液-液界面组装成微棒（C70MR），然后通过煅烧分解，生成不含金属的富勒烯衍生的ORR电催化剂。研究了热解温度对C70MRs的影响，发现900℃的热解有效地展开了C70笼，并将其转化为高度多孔、富含缺陷的碳材料（C70MRs-900），并且棒状形貌得到了良好的保留。这些结构特征赋予 C70MRs-900 出色的 ORR 活性和稳定性以及出色的甲醇耐受性，优于在较低温度 (800 °C) 或较高温度 (1000 °C) 下退火的 C70MR。此外，通过在 NH4Cl 存在下于 900 °C 退火 C70MR，氮原子成功地结合到有缺陷的碳骨架中。所得的 N 掺杂 C70MRs-900 表现出卓越的 ORR 性能，半波电位为 0.836 V，与商用 20% Pt/C 催化剂相当。这项工作提出了一种简单有效的途径，利用富勒烯分子作为起始材料来开发高性能的无金属、碳基电催化剂，以实现 ORR 甚至超越。
Disrupting the integrity of the sp2-carbon skeleton offers an effective strategy to create active sites for the oxygen reduction reaction (ORR). In this work, fullerene (C70) molecules, composed of 12 pentagons and 25 hexagons all bonded by sp2-C atoms, are assembled into microrods (C70MRs) at the liquid–liquid interface and then broken down by calcination to generate metal-free fullerene-derived ORR electrocatalysts. The effect of the pyrolysis temperature on C70MRs is investigated, and it is found that pyrolysis at 900 °C effectively unfolds the C70 cages and converts them into a highly porous, defect-rich carbon material (C70MRs-900) with the rod-shaped morphology well-retained. These structural features endow C70MRs-900 with outstanding ORR activity and stability together with remarkable methanol tolerance, better than C70MRs annealed at either lower (800 °C) or higher (1000 °C) temperatures. Furthermore, nitrogen atoms are successfully incorporated into the defective carbon skeleton by annealing C70MRs at 900 °C in the presence of NH4Cl. The resultant N-doped C70MRs-900 exhibits remarkable ORR performance with a half-wave potential of 0.836 V, comparable to that of the commercial 20% Pt/C catalyst. This work presents a simple and effective route of utilizing fullerene molecules as starting materials to develop high-performance metal-free, carbon-based electrocatalysts toward the ORR and even beyond.