Abdelrazek Ghada M, El-Deeb Mohamed M, Farghali Ahmed A, Pérez-Cadenas Agustín F, Abdelwahab Abdalla
Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences, Beni-Suef University, Beni-Suef 62511, Egypt.
Chemistry Department, Faculty of Engineering, Basic Science, Misr University for Science and Technology (MUST), 6th of October City, Giza 12566, Egypt.
Materials (Basel). 2021 Sep 13;14(18):5271. doi: 10.3390/ma14185271.
Layered double hydroxides (LDHs) have emerged as promising electrodes materials for the methanol oxidation reaction. Here, we report on the preparation of different LDHs with the hydrothermal process. The effect of the divalent cation (i.e., Ni, Co, and Zn) on the electrochemical performance of methanol oxidation was investigated. Moreover, nanocomposites of LDHs and carbon xerogels (CX) supported on nickel foam (NF) substrate were prepared to investigate the role of carbon xerogel. The results show that NiFe-LDH/CX/NF is an efficient electrocatalyst for methanol oxidation with a current density that reaches 400 mA·m compared to 250 and 90 mA·cm for NiFe-LDH/NF and NF, respectively. In addition, all LDH/CX/NF nanocomposites show excellent stability for methanol oxidation. A clear relationship is observed between the electrodes crystallite size and their activity to methanol oxidation. The smaller the crystallite size, the higher the current density delivered. Additionally, the presence of carbon xerogel in the nanocomposites offer 3D interconnected micro/mesopores, which facilitate both mass and electron transport.
层状双氢氧化物（LDHs）已成为甲醇氧化反应中很有前景的电极材料。在此，我们报道了通过水热法制备不同的LDHs。研究了二价阳离子（即镍、钴和锌）对甲醇氧化电化学性能的影响。此外，制备了负载在泡沫镍（NF）基底上的LDHs与碳干凝胶（CX）的纳米复合材料，以研究碳干凝胶的作用。结果表明，与NiFe-LDH/NF和NF分别达到的250和90 mA·cm²相比，NiFe-LDH/CX/NF是一种用于甲醇氧化的高效电催化剂，电流密度达到400 mA·cm²。此外，所有LDH/CX/NF纳米复合材料对甲醇氧化均表现出优异的稳定性。观察到电极微晶尺寸与其甲醇氧化活性之间存在明显关系。微晶尺寸越小，传递的电流密度越高。此外，纳米复合材料中碳干凝胶的存在提供了三维相互连接的微孔/介孔，这有利于质量和电子传输。
