High-Temperature Fuel Cell Research Department, Vali-e-Asr University of Rafsanjan, Rafsanjan P.O. Box 7718897111, Iran.
Department of Physics, Faculty of Science, University of Guilan, Rasht P.O. Box 41335-1914, Iran.
Molecules. 2023 Jun 7;28(12):4613. doi: 10.3390/molecules28124613.
Today, finding low-cost electro-catalysts for methanol and ethanol oxidation with high performance and stability is one of the new research topics. A nanocatalyst based on metal oxides in the form of MnMoO was synthesized by a hydrothermal method for methanol (MOR) and ethanol (EOR) oxidation reactions. Adding reduced graphene oxide (rGO) to the catalyst structure improved the electrocatalytic activity of MnMoO for the oxidation processes. The crystal structure and morphology of the MnMoO and MnMoO-rGO nanocatalysts were investigated by physical analyses such as scanning electron microscopy and X-ray diffraction. Their abilities for MOR and EOR processes in an alkaline medium were evaluated by performing electrochemical tests such as cyclic voltammetry, chronoamperometry, and electrochemical impedance spectroscopy. MnMoO-rGO showed oxidation current densities of 60.59 and 25.39 mA/cm and peak potentials of 0.62 and 0.67 V in MOR and EOR processes (at a scan rate of 40 mV/s), respectively. Moreover, stabilities of 91.7% in MOR and 88.6% in EOR processes were obtained from the chronoamperometry analysis within 6 h. All these features make MnMoO-rGO a promising electrochemical catalyst for the oxidation of alcohols.
如今，寻找具有高性能和高稳定性的低成本甲醇和乙醇氧化用电催化剂是一个新的研究课题。本文采用水热法合成了一种以 MnMoO 形式存在的金属氧化物纳米催化剂，用于甲醇（MOR）和乙醇（EOR）氧化反应。向催化剂结构中添加还原氧化石墨烯（rGO）可提高 MnMoO 对氧化过程的电催化活性。通过物理分析（如扫描电子显微镜和 X 射线衍射）研究了 MnMoO 和 MnMoO-rGO 纳米催化剂的晶体结构和形态。通过电化学测试（如循环伏安法、计时电流法和电化学阻抗谱）评估了它们在碱性介质中对 MOR 和 EOR 过程的能力。在 MOR 和 EOR 过程中（扫描速率为 40 mV/s），MnMoO-rGO 的氧化电流密度分别为 60.59 和 25.39 mA/cm，峰电位分别为 0.62 和 0.67 V。此外，通过计时电流法分析，在 6 小时内 MOR 和 EOR 过程的稳定性分别达到 91.7%和 88.6%。所有这些特性使 MnMoO-rGO 成为一种有前途的醇类氧化电化学催化剂。
