Ali Hagar, El Rouby Waleed M A, Khedr M H, Hmamm Mai F M
Materials Science and Nanotechnology Department, Faculty of Postgraduate Studies for Advanced Sciences (PSAS), Beni-Suef University 62511 Beni-Suef Egypt
Renewable Energy Science and Engineering Department, Faculty of Postgraduate Studies for Advanced Science, Beni-Suef University 62511 Beni-Suef Egypt.
Nanoscale Adv. 2025 Jul 14;7(16):5080-5092. doi: 10.1039/d5na00223k. eCollection 2025 Aug 5.
NiCoO nanosheets and nanoribbons were synthesized by calcining Ni-Co hydroxide and Ni-Co MOF precursors at 350 °C for two hours. These precursors were first synthesized hydrothermal and solvothermal techniques, with the goal of improving their efficiency in methanol electro-oxidation. These two different methodologies are the factors that affect the morphology and electrochemical performance of the resulting NiCoO under the same environmental conditions. The superior characteristics of NiCoO nanosheets, which showed high crystallinity, well-defined morphology, high porosity, and substantial surface area, were confirmed by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM), and nitrogen sorption measurements. Chronoamperometry (CA), electrochemical impedance spectroscopy (EIS), and cyclic voltammetry (CV) were used in an alkaline medium to perform electrochemical assessments for methanol oxidation. Remarkably, NiCoO nanosheets demonstrated excellent electrocatalytic activity, outperforming NiCoO nanoribbons with a minimal starting potential (0.32 V), elevated current density (70.36 mA cm), and good electro-oxidation stability (86%). Their distinct shape, which provides a high surface area and numerous functional sites for reaction, as well as enabling quick ion movement between the electrolyte and the electrode, is credited for the nanosheets' increased electrocatalytic efficiency. These results emphasize the potential of NiCoO nanosheets as electroactive catalysts for fuel cell applications.
通过在350℃下煅烧氢氧化镍钴和镍钴金属有机框架前驱体两小时，合成了镍钴氧化物纳米片和纳米带。这些前驱体首先采用水热和溶剂热技术合成，目的是提高它们在甲醇电氧化中的效率。在相同环境条件下，这两种不同的方法是影响所得镍钴氧化物的形态和电化学性能的因素。通过X射线衍射（XRD）、扫描电子显微镜（SEM）、能量色散光谱（EDS）、透射电子显微镜（TEM）和氮吸附测量，证实了镍钴氧化物纳米片具有优异的特性，表现出高结晶度、明确的形态、高孔隙率和大表面积。在碱性介质中，采用计时电流法（CA）、电化学阻抗谱（EIS）和循环伏安法（CV）对甲醇氧化进行电化学评估。值得注意的是，镍钴氧化物纳米片表现出优异的电催化活性，优于镍钴氧化物纳米带，起始电位最低（0.32V），电流密度升高（70.36mA/cm），电氧化稳定性良好（86%）。纳米片独特的形状为反应提供了高表面积和大量功能位点，并能使离子在电解质和电极之间快速移动，这归因于纳米片电催化效率的提高。这些结果强调了镍钴氧化物纳米片作为燃料电池应用中电活性催化剂的潜力。
