Abstract This paper aims at studying the electrochemical performance of carbon fibers (CF) from chemical treatment using nitric acid at different times (0–30 min) and their respective graphene oxide/carbon fiber (GO/CF) composites. The oxidative process introduced oxygenated functional groups on the CF surfaces. After the chemical treatment, CF samples showed cluster formations, which increased their surface roughness. Although the chemical treatment did not cause significant changes in CF structures, it promoted an electrochemical response enhancement. The electrochemical analyses showed a specific electrochemical surface area increased from 174.0 (CF0) to 582.1 cm2 cm−3 (CF30). The treated CF presented more capacitive profile than that of the untreated electrode. CF30 showed a capacitance increase of around 1625% compared to that of CF0. GO incorporation also provided better electrochemical responses for GO/CF composites, which presented lower equivalent series resistances than those of their respective CF during galvanostatic charge/discharge curves. GO/CF30 depicted a capacitance increase of around 8250% compared to that of GO/CF0 composite. These results pointed out the oxidative process control importance in carbon materials aiming at their application for supercapacitors.

中文翻译：

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使用有前景的 CF 蚀刻增强 CF 和 GO/CF 复合材料的电化学响应

摘要 本文旨在研究不同时间（0-30 分钟）使用硝酸进行化学处理的碳纤维（CF）及其各自的氧化石墨烯/碳纤维（GO/CF）复合材料的电化学性能。氧化过程在 CF 表面引入了氧化官能团。化学处理后，CF 样品显示簇形成，这增加了它们的表面粗糙度。虽然化学处理没有引起 CF 结构的显着变化，但它促进了电化学响应的增强。电化学分析表明比电化学表面积从 174.0 (CF0) 增加到 582.1 cm2 cm-3 (CF30)。处理过的 CF 呈现出比未处理电极更大的电容分布。与CF0相比，CF30的电容增加了约1625%。GO 掺入还为 GO/CF 复合材料提供了更好的电化学响应，在恒电流充电/放电曲线期间，GO/CF 复合材料的等效串联电阻低于其各自 CF 的等效串联电阻。与 GO/CF0 复合材料相比，GO/CF30 的电容增加了约 8250%。这些结果指出了碳材料中氧化过程控制的重要性，旨在将其应用于超级电容器。