Abstract We employed the oxidative dehydrogenation of C2H2 by CO2 and the C2H2 decomposition to prepare carbon nanotubes (CNTs) and carbon nanofibers (CNFs). The use of a small amount of Ni catalyst made it possible to produce CNTs and CNFs having a highly defective structure at a relatively low temperature compared to the one typically used for the CNT synthesis. The synthesized CNTs and CNFs were decorated with about 10 nm-gold nanoparticles (AuNPs) via an electrostatic self-attachment. The electrode with CNTs synthesized via the C2H2–CO2 reaction exhibits superior electrochemical reactivity with H2O2 when compared to the ones with CNTs synthesized via C2H2 decomposition, commercial CNTs, CNFs, and other more common carbon supports e.g. carbon black and activated charcoal. It demonstrates a rapid response, high sensitivity (104.9 μA mM−1 cm−2), wide linear working range (5 μM–23 mM), low detection limit (0.138 μM), good selectivity, reproducibility, and stability. The CNTs synthesized via the C2H2–CO2 reaction are suggested as energy-saving, cost-effective and environmentally friendly supporting material candidates for practical applications. The electrodes with CNTs show a high electrochemically active surface area, low charge transfer resistance and fast mass transfer at the electrode surface that are key factors for H2O2 detection.

中文翻译：

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用于敏感、低成本和环保电化学 H2O2 传感器的高缺陷碳纳米管：深入了解碳载体

摘要 我们利用 CO2 对 C2H2 的氧化脱氢和 C2H2 分解制备了碳纳米管 (CNTs) 和碳纳米纤维 (CNFs)。与通常用于 CNT 合成的催化剂相比，使用少量 Ni 催化剂可以在相对较低的温度下生产具有高度缺陷结构的 CNT 和 CNF。合成的 CNTs 和 CNFs 通过静电自附着用约 10 nm 的金纳米粒子 (AuNPs) 装饰。与通过 C2H2 分解、商业碳纳米管、CNF 和其他更常见的碳载体（例如炭黑和活性炭）合成的碳纳米管相比，通过 C2H2-CO2 反应合成的碳纳米管电极与 H2O2 显示出优异的电化学反应性。它表现出快速响应、高灵敏度 (104.9 μA mM-1 cm-2)，宽线性工作范围 (5 μM–23 mM)、低检测限 (0.138 μM)、良好的选择性、重现性和稳定性。通过 C2H2-CO2 反应合成的碳纳米管被认为是节能、经济、环保的实际应用候选材料。具有碳纳米管的电极显示出高电化学活性表面积、低电荷转移电阻和电极表面的快速传质，这些是 H2O2 检测的关键因素。