Ghazal Nurhan, Madkour Metwally, Abdel Nazeer Ahmed, Obayya S S A, Mohamed Shaimaa A
Centre for Photonics and Smart Materials, Zewail City of Science and Technology October Gardens 6th of October City Giza Egypt.
Chemistry Department, Faculty of Science, Kuwait University P. O. Box 5969 Safat 13060 Kuwait
RSC Adv. 2021 Dec 8;11(62):39262-39269. doi: 10.1039/d1ra07455e. eCollection 2021 Dec 6.
In this paper, we studied the electrochemical capacitive performance of thermally evaporated copper iodide thin film doped with different quantities of Al (3, 5, 7, and 9 mol%). The morphological structure, crystalline nature, and surface composition of the deposited films with different dopant levels were confirmed using X-ray powder diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and field-emission scanning electron microscopy (FE-SEM). The electrochemical performance was evaluated based on cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) measurements, and electrochemical impedance spectroscopy (EIS) in a NaSO electrolyte. The XRD results confirm that the film is crystalline and has a face-centered cubic structure. The SEM images revealed trihedral-tipped structures with irregular nanocubes. The presence of the trihedral-tipped structures is more obvious in the Al-doped CuI films than in the bare film. We report a progressive increase in the specific capacitance values as the aluminum content increases, from 91.5 F g for the pure CuI film to 108.3, 126.2, 142.8, and 131.1 F g for the films with aluminum content of 3, 5, 7, and 9 mol%, respectively at a scan rate of 2 mV s. The optimized CuI-Al electrode with 7 mol% aluminum content showed remarkable long-term cycling stability with 89.1% capacitance retention after 2000 charge/discharge cycles. Such a high performance for the CuI-7Al film as a supercapacitor can be ascribed to the aluminum doping, which increases the electrochemically active area compared to the bare CuI film and is critical for electron exchange at the electrode/electrolyte interface. Therefore, we introduce CuI-Al as a viable option for supercapacitor applications because of its low-cost production, excellent electrochemical performance, and cycling stability.
在本文中，我们研究了掺杂不同量铝（3、5、7和9摩尔%）的热蒸发碘化铜薄膜的电化学电容性能。使用X射线粉末衍射（XRD）、X射线光电子能谱（XPS）和场发射扫描电子显微镜（FE-SEM）确定了不同掺杂水平沉积薄膜的形态结构、晶体性质和表面组成。在NaSO电解质中，基于循环伏安法（CV）、恒电流充放电（GCD）测量和电化学阻抗谱（EIS）对电化学性能进行了评估。XRD结果证实该薄膜为晶体，具有面心立方结构。扫描电子显微镜图像显示出具有不规则纳米立方体的三面尖结构。在掺铝的CuI薄膜中，三面尖结构的存在比在裸膜中更明显。我们报告了随着铝含量的增加，比电容值逐渐增加，在扫描速率为2 mV s时，纯CuI薄膜的比电容为91.5 F g，铝含量为3、5、7和9摩尔%的薄膜的比电容分别为108.3、126.2、142.8和131.1 F g。铝含量为7摩尔%的优化CuI-Al电极显示出显著的长期循环稳定性，在2000次充放电循环后电容保持率为89.1%。CuI-7Al薄膜作为超级电容器具有如此高的性能可归因于铝掺杂，与裸CuI薄膜相比，铝掺杂增加了电化学活性面积，这对电极/电解质界面的电子交换至关重要。因此，由于其低成本生产、优异的电化学性能和循环稳定性，我们将CuI-Al作为超级电容器应用的一个可行选择。
