Morphological and chemical features of nano and macroscale carbons affecting hydrogen peroxide decomposition in aqueous media
Morphological and chemical features of nano and macroscale carbons affecting hydrogen peroxide decomposition in aqueous media
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DOI：
10.1016/j.jcis.2011.05.048
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发表时间：
2011-09-01
影响因子：
9.9
通讯作者：
Mikhalovsky, Sergey V.
中科院分区：
文献类型：
--
作者：
Voitko, Kateryna V.;Whitby, Raymond L. D.;Mikhalovsky, Sergey V.
碳材料的化学和结构因素影响其在水介质中的吸附和表面反应活性。所研究的过氧化氢分解是探索可能涉及的碳的参数的探针反应，例如比表面积、氮和氧掺杂以及构象变化。到目前为止，碳纳米级（碳纳米管，CNT，单层氧化石墨烯，SLGO）与宏观级（活性炭，AC）材料在该反应中的行为的详细比较尚未出现。在此，我们证明，在他们的第一个周期，AC在掺杂和未掺杂的形式优于所有纳米级碳在H2O2分解测试。在纳米碳中，氮掺杂的CNT在该反应中表现出最高的活性。然而，在使用之间没有化学再生的情况下，每种碳的后续再循环揭示了SLGO在延长的循环次数（n > 8）内表现出比包括氮掺杂的CNT和AC的其它碳更大的反应速率稳定性。分析了pH值、温度和浓度对反应的影响。量子化学建模和反应动力学分析揭示了可能参与过氧化氢分解的关键过程，并显示了反应速率与含N和O官能团的活性位点有关的证据。(C)2011 Elsevier Inc. All rights reserved.
Chemical and structural factors of carbon materials affect their activity in adsorption and surface reactions in aqueous media. Decomposition of hydrogen peroxide studied is a probe reaction for exploring parameters of carbons that might be involved, such as specific surface area, nitrogen and oxygen doping and conformational changes. To date, a detailed comparison of the behavior of carbon nanoscale (Carbon Nanotubes, CNT, Single Layer Graphene Oxide, SLGO) with macroscale (Activated carbons, AC) materials in this reaction has not been forthcoming. Herein, we demonstrate that on their first cycle, ACs in doped and undoped forms outperform all nanoscale carbons tested in the H2O2 decomposition. Among the nanocarbons, nitrogen-doped CNT exhibited the highest activity in this reaction. However, subsequent recycling of each carbon, without chemical regeneration between uses, reveals SLGO exhibits greater reaction rate stability over an extended number of cycles (n > 8) than other carbons including nitrogen-doped CNT and ACs. The effects of pH, temperature and concentration on the reaction were analyzed. Quantum-chemical modeling and reaction kinetics analysis reveal key processes likely involved in hydrogen peroxide decomposition and show evidence that the reaction rate is linked to active sites with N-and O-containing functionalities. (C) 2011 Elsevier Inc. All rights reserved.