Key Laboratory of Nanobiosensing and Nanobioanalysis at Universities of Jilin Province, Faculty of Chemistry, Northeast Normal University, Changchun 130024, PR China.
Key Laboratory of Nanobiosensing and Nanobioanalysis at Universities of Jilin Province, Faculty of Chemistry, Northeast Normal University, Changchun 130024, PR China.
J Colloid Interface Sci. 2019 Jan 1;533:578-587. doi: 10.1016/j.jcis.2018.08.118. Epub 2018 Sep 1.
Exploring highly active, inexpensive and robust electrocatalysts for oxygen reduction reaction (ORR) is of great significance as a competitive alternative to noble metal-based catalysts in energy conversion and storage devices. In the present study, we design a novel ORR electrocatalyst of iron-cobalt (FeCo) alloy nanoparticles embedded on N-doped porous carbon nanofibers (FeCo@PCNF-T) by electrospinning of [Polyacrylonitrile (PAN)/Prussian blue analogues/CaCO] and post-calcination treatment. The obtained catalysts with bimetallic active sites show unique three-dimensional (3D) hierarchical meso/macropores structures. FeCo alloy nanoparticles are encapsulated into graphitic carbon that can increase stability and provide additional catalytic active sites. Under the optimized condition, FeCo@PCNF-800 displays excellent ORR electrocatalytic activity in alkaline solutions, with a more positive half-wave potential (E of 0.854 V vs RHE) and larger limited-diffusion current density (j of 6.012 mA cm) than those of 20 wt% Pt/C (E of 0.849 V and j of 5.710 mA cm). In addition, FeCo@PCNF-800 also exhibits comparable ORR electrocatalytic activity in acidic solutions to those of 20 wt% Pt/C with onset potential and half-wave potential as more positive as 0.843 V vs RHE and 0.739 V vs RHE, respectively. Moreover, FeCo@PCNF-800 exhibits excellent tolerance towards methanol, stability and a four-electron pathway in both basic and acidic solutions. The excellent ORR electrocatalytic activity performance of FeCo@PCNF-800 is attributed to the synergistic effect of the FeCo alloy nanoparticles and N-doped porous carbon nanofibers. The synergistic effect can improve the mass and charge transport capability and increase active sites of FeCo-N-C. Furthermore, this work offers a new insight for the reasonable design and development of efficient non-noble metal electrocatalysts for challenging electrochemical energy-related technologies.
探索高效、廉价且稳定的氧还原反应（ORR）电催化剂作为替代贵金属基催化剂在能源转换和存储设备中的应用具有重要意义。在本研究中，我们通过静电纺丝[聚丙烯腈（PAN）/普鲁士蓝类似物/CaCO]和后煅烧处理，设计了一种新型的铁钴（FeCo）合金纳米粒子嵌入氮掺杂多孔碳纳米纤维（FeCo@PCNF-T）的 ORR 电催化剂。具有双金属活性位的所得催化剂具有独特的三维（3D）分级中/大孔结构。FeCo 合金纳米粒子被包裹在石墨碳中，这可以提高稳定性并提供额外的催化活性位。在优化条件下，FeCo@PCNF-800 在碱性溶液中表现出优异的 ORR 电催化活性，具有更正的半波电位（E 为 0.854 V 相对于 RHE）和更大的极限扩散电流密度（j 为 6.012 mA cm），优于 20 wt%Pt/C（E 为 0.849 V 和 j 为 5.710 mA cm）。此外，FeCo@PCNF-800 在酸性溶液中的 ORR 电催化活性与 20 wt%Pt/C 相当，其起始电位和半波电位分别为更正的 0.843 V 相对于 RHE 和 0.739 V 相对于 RHE。此外，FeCo@PCNF-800 在碱性和酸性溶液中均表现出对甲醇的优异耐受性、稳定性和四电子途径。FeCo@PCNF-800 的优异 ORR 电催化活性性能归因于 FeCo 合金纳米粒子和 N 掺杂多孔碳纳米纤维的协同效应。协同效应可以提高质量和电荷传输能力，并增加 FeCo-N-C 的活性位。此外，这项工作为合理设计和开发用于具有挑战性的电化学能源相关技术的高效非贵金属电催化剂提供了新的思路。
