当前位置: X-MOL 学术Electrochim. Acta › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Carbon catalysts for electrochemical hydrogen peroxide production in acidic media
Electrochimica Acta ( IF 6.6 ) Pub Date : 2018-04-03
Viktor Čolić, Sungeun Yang, Zsolt Révay, Ifan E.L. Stephens, Ib Chorkendorff

Hydrogen peroxide is a commodity chemical, as it is an environmentally friendly oxidant. The electrochemical production of H2O2 from oxygen and water by the reduction of oxygen is of great interest, as it would allow the decentralized, on-site, production of pure H2O2. The ability to run the reaction in an acidic electrolyte with high performance is particularly important, as it would allow the use of polymer solid electrolytes and the production of pH-neutral hydrogen peroxide. Carbon catalysts, which are cheap, abundant, durable and can be highly selective show promise as potential catalysts for such systems. In this work, we examine the electrocatalytic performance and properties of seven commercially available carbon materials for H2O2 production by oxygen electroreduction. We show that the faradaic efficiencies for the reaction lie in a wide range of 18–82% for different carbon catalysts. In order to determine the cause of these differences, we employ prompt gamma ray/neutron activation analysis and XPS measurements to assess the contribution of heteroatoms and defects, as well as low temperature N2-adsorption and transmission electron microscopy to elucidate the particle size, shape, BET surface area and porosity. We find that the surface oxygen groups, nitrogen and sulphur content display effects that are not straightforward, because their chemical state is likely significant. The metal content (when present in the order of magnitude of ∼10 ppm) is not a straightforward indicator of the electrocatalytic performance for this reaction. XPS and BET data indicate that carbons displaying high selectivities for the 2-electron process contain more aliphatic-like, “defect” structures on the surface.



中文翻译:

在酸性介质中生产电化学过氧化氢的碳催化剂

过氧化氢是一种商品化学品,因为它是一种环境友好的氧化剂。通过氧气的还原由氧气和水中的H 2 O 2的电化学生产备受关注,因为它将允许分散的,现场生产纯H 2 O 2。。在酸性电解质中进行高性能反应的能力尤为重要,因为这将允许使用聚合物固体电解质并产生pH中性的过氧化氢。廉价,丰富,耐用且可以高度选择性的碳催化剂显示出作为此类系统的潜在催化剂的希望。在这项工作中,我们研究了7种市售碳材料对H 2 O 2的电催化性能和性能。通过氧气电还原生产。我们表明,对于不同的碳催化剂,反应的法拉第效率在18-82%的范围内。为了确定这些差异的原因,我们采用了快速的伽马射线/中子活化分析和XPS测量来评估杂原子和缺陷以及低温N 2的贡献。-吸附和透射电子显微镜,以阐明粒径,形状,BET表面积和孔隙率。我们发现表面的氧基团,氮和硫的含量显示出的影响并不直接,因为它们的化学状态可能很重要。金属含量(当以〜10 ppm的数量级存在时)不是该反应的电催化性能的直接指标。XPS和BET数据表明,对2电子过程显示出高选择性的碳在表面上包含更多类似脂族的“缺陷”结构。

更新日期:2018-04-03
down
wechat
bug