Guo Xingmei, Liu Shanjing, Wan Xiaohan, Zhang Junhao, Liu Yuanjun, Zheng Xiangjun, Kong Qinghong, Jin Zhong
School of Environmental and Chemical Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003, People's Republic of China.
MOE Key Laboratory of Mesoscopic Chemistry, MOE Key Laboratory of High Performance Polymer Materials and Technology, Jiangsu Key Laboratory of Advanced Organic Materials, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, People's Republic of China.
Nano Lett. 2022 Jun 22;22(12):4879-4887. doi: 10.1021/acs.nanolett.2c01318. Epub 2022 May 31.
Preparing advanced electrocatalysts via solid-phase reactions encounters the challenge of low controllability for multiconstituent hybridization and microstructure modulation. Herein, a hydrothermal-mimicking solid-phase system is established to fabricate novel FeO/FeC/Fe-N-C composites consisting of FeO/FeC nanoparticles and Fe,N-doped carbon species with varying morphologies. The evolution mechanism featuring a competitive growth of different carbon sources in a closed hypoxic space is elucidated for a series of FeO/FeC/Fe-N-C composites. The size and dispersity of FeO/FeC nanoparticles, the graphitization degree of the carbonaceous matrix, and their diverse hybridization states lead to disparate electrocatalytic behaviors for the oxygen reduction reaction (ORR). Among them, microspherical FeO/FeC/Fe-N-C-3 exhibits an optimal ORR performance and the as-assembled zinc-air battery shows all-round superiority to the Pt/C counterpart. This work presents a mild solid-phase fabrication technique for obtaining a variety of nanocomposites with effective control over composition hybridization and microstructural modulation, which is significantly important for the design and optimization of advanced electrocatalysts.
通过固相反应制备先进的电催化剂面临着多组分杂化和微观结构调控可控性低的挑战。在此，建立了一种水热模拟固相体系，以制备由具有不同形貌的FeO/FeC纳米颗粒和Fe、N掺杂碳物种组成的新型FeO/FeC/Fe-N-C复合材料。阐明了一系列FeO/FeC/Fe-N-C复合材料在封闭缺氧空间中不同碳源竞争生长的演化机制。FeO/FeC纳米颗粒的尺寸和分散性、碳质基体的石墨化程度及其不同的杂化状态导致氧还原反应（ORR）的电催化行为不同。其中，微球形FeO/FeC/Fe-N-C-3表现出最佳的ORR性能，组装后的锌空气电池相对于Pt/C对应物具有全方位的优势。这项工作提出了一种温和的固相制备技术，用于获得各种对组成杂化和微观结构调控具有有效控制的纳米复合材料，这对先进电催化剂的设计和优化具有重要意义。
