Oxygen evolution reaction over copper and zinc co-doped LaFeO3 perovskite oxides
Oxygen evolution reaction over copper and zinc co-doped LaFeO3 perovskite oxides
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DOI：
10.1016/j.poly.2018.09.031
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发表时间：
2018-12
期刊：
影响因子：
2.6
通讯作者：
E. Omari;M. Omari;D. Barkat
中科院分区：
文献类型：
--
作者：
E. Omari;M. Omari;D. Barkat
以柠檬酸为前驱体，采用溶胶凝胶法合成了分子式为 LaFe1−xZnx/2Cux/2O3(0≤x≤0.3) 的新型钙钛矿型氧化物。使用 TGA/DTA、XRD、IR、SEM、循环伏安法、阻抗和塔菲尔极化技术研究了它们在碱性溶液中析氧的物理化学和电催化特性。 X射线衍射表明，在750℃下煅烧的样品在0≤x≤0.2范围内呈现出纯钙钛矿结构。 FTIR 光谱证实了 FeO6 八面体中 Fesingle bondO 金属氧键的存在。扫描电子显微镜（SEM）显示不同形状的颗粒团聚。对每种氧化物催化剂在 1M KOH 中的析氧反应 (OER) 研究显示，在低过电势和高过电势下分别有两个塔菲尔斜率 (b1≈60mV/dec) 和 (b2≈120mV/dec)。 LaFe0.8Zn0.1Cu0.1O3在0.66V下实现了最高的电极活性性能。EIS研究是为了研究氧化物晶格中铁被锌和铜部分取代对OER催化性能以及氧化膜/1M KOH界面的影响。
New perovskite – type oxides with molecular formula LaFe1−xZnx/2Cux/2O3(0 ≤x≤ 0.3) were synthesized by sol–gel method involving citric acid as precursor. Their physicochemical and electro-catalytic properties towards O2-evolution in alkaline solutions have been investigated using TGA/DTA, XRD, IR, SEM, cyclic voltammetry, impedance and Tafel polarization techniques. The X-ray diffraction indicated that samples calcined at 750 °C, exhibit a pure perovskite structure in the range 0 ≤x≤ 0.2. The FTIR spectra confirm the presence of metal oxygen bond of Fesingle bondO in the FeO6octahedra. Scanning electron microscopy (SEM) show the agglomeration of the particles with different shapes. The oxygen evolution reaction (OER) study on each oxide catalyst in 1 M KOH showed two Tafel slopes, (b1≈ 60 mV/dec) and (b2≈ 120 mV/dec) at low and high over-potentials respectively. The highest electrode activity performance is achieved with LaFe0.8Zn0.1Cu0.1O3at 0.66 V. The EIS study was carried out to investigate the effect of the partial substitution of iron by zinc and copper in the oxide lattice, on the catalytic performance towards the OER and also on the oxide film/1 M KOH interface.