纤维状多孔钙锰氧化物制备及其氧还原反应电催化活性

发布时间：2018-03-26 19:01

本文选题：海藻酸钙纤维　切入点：非贵金属催化剂　出处：《无机材料学报》2017年05期

【摘要】：首次以海藻酸钙纤维为载体制得层状钙钛矿结构的Ca_2MnO_4钙锰氧化物(Ca-Mn-O),并以尖晶石结构的CaMn_3O_6为对比样,测试了样品作为电化学氧还原催化剂(ORR)的性能。通过XRD、FE-SEM、TEM和BET对材料进行表征,结果表明该层状-钙钛矿结构的氧化物具有内部相互交联的多孔网状结构和大的比表面积。电催化测试结果表明:Ca_2MnO_4氧化物具有明显的催化活性,高的极限扩散电流密度、接近四电子氧化还原以及在碱性溶液中较低产率的过氧化氢,说明这种廉价而丰富的ORR催化剂具有潜在的应用前景。Ca-Mn-O氧化物的催化活性(初始还原电位、极限电流密度以及电子转移数)很大程度依赖于表面Mn的氧化态和晶体结构。此外,大的比表面积和多孔网状结构,增多了氧还原反应的电催化活性位;高的氧空位浓度有利于氧还原反应的进行;合适的晶体结构具有开放的空间,有利于氧的吸附。
[Abstract]:For the first time, the layered perovskite Ca_2MnO_4 perovskite Ca_2MnO_4 oxide was prepared by using calcium alginate fiber as the carrier, and the spinel structure of CaMn_3O_6 was used as the contrast sample. The properties of the sample as an electrochemical oxygen reduction catalyst (ORR) were tested. The materials were characterized by XRDX FE-SEM TEM and BET. The results show that the oxide with layered perovskite structure has a porous network structure and a large specific surface area. The results of electrocatalysis test show that the oxide has obvious catalytic activity and high limit diffusion current density. Close to tetraelectron redox and low yield hydrogen peroxide in alkaline solution, this cheap and abundant ORR catalyst has a potential application prospect. The catalytic activity of Ca-Mn-O oxides (initial reduction potential), The limit current density and electron transfer number depend largely on the oxidation state and crystal structure of mn on the surface. In addition, the large specific surface area and porous network structure increase the electrocatalytic active sites of oxygen reduction reaction. High oxygen vacancy concentration is conducive to oxygen reduction reaction, and suitable crystal structure has an open space, which is conducive to oxygen adsorption.
【作者单位】：河南师范大学化学化工学院;河南省电池研究院;
【基金】：河南省科技攻关项目(152102210080) 河南省教育厅科学技术研究重点项目(12B480002) 河南省科技攻关计划(国际科技合作)(162102410047)~~
【分类号】：O643.36;TM911.4

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