Hashemzadeh Seyedeh Maryam, Khorshidi Alireza, Arvand Majid
Department of Inorganic Chemistry, Faculty of Chemistry, University of Guilan, P.O. Box: 41335-1914, Rasht, Iran.
Sci Rep. 2025 Mar 24;15(1):10064. doi: 10.1038/s41598-025-95338-7.
This study has focused on enhancing the effectiveness of supercapacitors, which are crucial for energy storage applications. Traditionally, supercapacitors have faced challenges in achieving higher energy density than batteries. This study hypothesizes that modifying the anionic structure of lithium cobalt oxide can significantly improve supercapacitors' energy density and charge storage capability. Lithium cobalt oxide was synthesized by sol-gel method, and LiCoO(FCl) with x = 0.1, 0.2, and 0.4 (F = 0.8x, Cl = 0.2x), was obtained by anion-exchange method. The structure and crystalline nature of the synthesized samples were analyzed using Fourier-transform infrared spectroscopy, powder X-ray diffraction, and X-ray photoelectron spectroscopy. To further confirm the correctness of the structures, microstructural and morphological studies were conducted using Field emission scanning electron microscopy and Transmission electron microscopy. The charge-discharge investigations showed that the electrode made of LiCoO(FCl) had a high specific capacitance (522.16 F g at a current density of 1 A g) compared to the Lithium Cobalt Oxide electrode. In addition, it showed a fabulous cycle life stability with 92.04% coulombic efficiency after 4000 charge-discharge cycles.
本研究聚焦于提高超级电容器的效能，超级电容器对于能量存储应用至关重要。传统上，超级电容器在实现比电池更高的能量密度方面面临挑战。本研究假设，改变锂钴氧化物的阴离子结构可显著提高超级电容器的能量密度和电荷存储能力。通过溶胶-凝胶法合成了锂钴氧化物，并通过阴离子交换法获得了x = 0.1、0.2和0.4（F = 0.8x，Cl = 0.2x）的LiCoO(FCl)。使用傅里叶变换红外光谱、粉末X射线衍射和X射线光电子能谱对合成样品的结构和晶体性质进行了分析。为进一步确认结构的正确性，使用场发射扫描电子显微镜和透射电子显微镜进行了微观结构和形态学研究。充放电研究表明，与锂钴氧化物电极相比，由LiCoO(FCl)制成的电极具有较高的比电容（在电流密度为1 A g时为522.16 F g）。此外，在4000次充放电循环后，它显示出出色的循环寿命稳定性，库仑效率为92.04%。
