Yang Min, Lao Xianzhuo, Sun Jing, Ma Ning, Wang Shuqing, Ye Wanneng, Guo Peizhi
Institute of Materials for Energy and Environment, State Key Laboratory of Bio-fibers and Eco-textiles, College of Materials Science and Engineering, Qingdao University, Qingdao 266071, P. R. China.
Langmuir. 2020 Sep 22;36(37):11094-11101. doi: 10.1021/acs.langmuir.0c02102. Epub 2020 Sep 4.
The direct ethanol fuel cells in an alkaline medium have a broad vision of applications because of their large energy density, reasonable power density, and environmentally friendly features. Herein, we present a facile one-step method to synthesize PdAg nanosheet assemblies (NSAs) in a mixed solution of ,-dimethylformamide and water with the addition of molybdenum hexacarbonyl and cetyltrimethylammonium bromide. Pure Pd NSA shows an irregular shape while PdAg NSAs gradually undergo a process from solid assembly to a hollow structure with the Pd/Ag molar ratio changing from 3:1 to 2:1 to 1:1. The formation of alloy nanosheets in the assemblies combined with the introduction of Ag in the Pd catalyst enhances the catalytic activity toward ethanol electrooxidation from 1524 mA mg of pure Pd NSA to 1866 mA mg of PdAg NSA with a Pd/Ag molar ratio of 2:1. On the basis of the experimental data, compared with pure Pd structures, both the nature of a thin nanosheet of PdAg NSAs and the structural changes in the alloy assemblies play key roles in determining the electrocatalytic activity of these Pd-based catalysts.
碱性介质中的直接乙醇燃料电池因其能量密度大、功率密度合理且环境友好等特点而具有广阔的应用前景。在此，我们提出了一种简便的一步法，即在N，N-二甲基甲酰胺和水的混合溶液中加入六羰基钼和十六烷基三甲基溴化铵来合成钯银纳米片组装体（NSA）。纯钯NSA呈现不规则形状，而钯银NSA随着钯/银摩尔比从3:1变为2:1再变为1:1，逐渐经历从固体组装体到空心结构的过程。组装体中合金纳米片的形成以及钯催化剂中银的引入，使乙醇电氧化的催化活性从纯钯NSA的1524 mA mg提高到钯/银摩尔比为2:1的钯银NSA的1866 mA mg。基于实验数据，与纯钯结构相比，钯银NSA的薄纳米片性质以及合金组装体中的结构变化在决定这些钯基催化剂的电催化活性方面都起着关键作用。
