Facile preparation of N-doped hierarchically porous carbon derived from pitch-based hyper-cross-linked polymers as an efficient metal-free catalyst for oxygen-reduction
Facile preparation of N-doped hierarchically porous carbon derived from pitch-based hyper-cross-linked polymers as an efficient metal-free catalyst for oxygen-reduction
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DOI：
10.1016/j.apsusc.2021.150579
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发表时间：
2021-11
影响因子：
6.7
通讯作者：
Yue Yang;Zhuo-Li He;Y. Liu;Shaolei Wang;Heng‐guo Wang;G. Zhu
中科院分区：
文献类型：
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作者：
Yue Yang;Zhuo-Li He;Y. Liu;Shaolei Wang;Heng‐guo Wang;G. Zhu
沥青作为石油和煤化工的副产品，迫切需要通过扩大其应用范围来提高其潜在价值。利用廉价易得的碳前驱体，设计和制备性能优异、稳定性高的无金属电催化剂用于氧还原反应已成为一种研究趋势。本文结合上述要求，以沥青基超交联聚合物(PHCPs)为碳源，通过简单的氨活化工艺制备了一种N掺杂的多层多孔炭材料作为ORR电催化剂。在优化的裂解温度(90 0℃)下，优化的N-PHCP-90 0具有999m2g−1的高比表面积、层次化的孔结构、丰富的活性氮和较高的缺陷密度。得益于这些特殊的优势，N-PHCP-900表现出出色的ORR性能，具有正的半波电位(0.883伏vs.RHE)和在碱性电解液中的坚固耐用性，超过了商用铂/C和大多数非贵金属电催化剂。因此，本工作不仅为开发价格低廉、高效的无金属ORR电催化剂提供了一种新的范式，而且为实现沥青的高附加值应用探索了一条可行的途径。
Pitch, as a by-product of the petroleum and coal chemical industry, is in great need of improving its potential value by expanding its application areas. Using low-cost and available carbon precursors and facile preparation to design and prepare metal-free electrocatalysts with preeminent performance and high stability for oxygen reduction reaction (ORR) have become a research trend. Herein, we combine the above-mentioned requirements to prepare a kind of N-doped hierarchical porous carbon materials as ORR electrocatalysts using pitch-based hyper-cross-linked polymers (PHCPs) as carbon precursors by a simple ammonia activation process. Under the optimized pyrolysis temperature (900 °C), the optimal N-PHCP-900 owns high specific surface area of 999 m2g−1, hierarchical pore structure, plentiful accessible active N and high density of defects. Benefitting from these special advantages, the N-PHCP-900 exhibits an outstanding ORR property with a positive half-wave potential (0.883 V vs. RHE) and robust durability in alkaline electrolyte, which surpass those for commercial Pt/C and the majority of non-noble metal electrocatalysts. Therefore, this work not only offers a novel paradigm in the development of affordable and efficient metal-free ORR electrocatalysts as the hopeful candidate, but also explores a feasible method for realizing the high value-added application of pitch.