MnO2-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media
MnO2-Based Nanostructures as Catalysts for Electrochemical Oxygen Reduction in Alkaline Media
复制标题
DOI：
10.1021/cm901698s
复制
发表时间：
2010-02-09
影响因子：
8.6
通讯作者：
Chen, Jun
中科院分区：
文献类型：
--
作者：
Cheng, Fangyi;Su, Yi;Chen, Jun
本文系统研究了碱性介质中MnO 2基纳米结构作为低成本氧还原催化剂的电化学性能。结果表明，MnO 2的催化活性与其晶体结构密切相关，其顺序为（α- > β- > γ-MnO 2）。同时，形貌也是影响电化学性能的另一个重要因素。在各种微米和纳米结构中，α-MnO 2纳米球和纳米线优于对应的微粒。此外，通过在α-MnO 2纳米线上沉积Ni纳米颗粒（表示为MnO 2-NWs@Ni-NPs）制备并表征了新的纳米复合催化剂。结果表明，MnO 2-NWs@Ni-NPs纳米复合材料的起始电位为0.08 V，比电流为33.5 mA/mg，氧还原反应全部为准4电子转移，表明其作为氧还原反应的电催化剂具有潜在的应用前景。
This paper reports a systematical study on the electrochemical properties of MnO2-based nanostructures as low-cost catalysts for oxygen reduction reaction (ORR) in alkaline media. The results show that the catalytic activities of MnO2 depend strongly on the crystallographic structures, following an order of (alpha- > beta- > gamma-MnO2. Meanwhile, morphology is another important influential factor to the electrochemical properties. Among various micro and nanostructures, alpha-MnO2 nanospheres and nanowires outperform the counterpart microparticles. Furthermore, a new nanocomposite catalyst by depositing Ni nanoparticles on alpha-MnO2 nanowires (denoted as MnO2-NWs@Ni-NPs) was prepared and characterized. The as-prepared MnO2-NWs@Ni-NPs nanocomposite exhibits an onset potential of 0.08 V, a specific current of 33.5 mA/mg, and all overall quasi 4-electron transfer involved in oxygen reduction reaction, indicating its potential application as the electrocatalyst of oxygen reduction reaction.