常壓噴射電漿超快速製備硫酸、氯化鋰、硫酸鋰凝膠態電解質還原氧化石墨烯-鋰錳氧化物超級電容器

Abstract

本研究使用網印技術在碳布基材上沉積還原氧化石墨烯（rGO）-鋰錳氧化物（LiMnOx）奈米複合前驅物，接著利用氮氣常壓噴射式電漿（Atmospheric-Pressure Plasma Jet, APPJ）進行了超快速(<300秒)的焙燒處理，並使用硫酸（H2SO4）、氯化鋰（LiCl）和硫酸鋰（Li2SO4）三種凝膠態電解質製備具有還原氧化石墨烯（rGO）-鋰錳氧化物（LiMnOx）奈米複合電極的混合型超級電容器。通過分析表面特徵及電化學測量結果來比較不同電漿處理時間的影響，並探討了三種凝膠態電解質對電極性能的影響。 以面積電容、能量密度和循環穩定性等電化學分析結果及電解質的性能特點來評估混合型超級電容器中電極材料與電解質的相容性。研究顯示，電漿處理後大幅改善混合型超級電容器之性能。在所製備之混合型超級電容器中，使用硫酸鋰凝膠態電解質表現出最佳的面積電容值和能量密度。此情形源於其具有高擬電容效應（PC）和鋰離子遷移速率，增強了電極-電解質界面反應和有效表面積。此外，嵌入的鋰離子與電雙層電容（EDLC）的耦合進一步促進了整體電容的顯著增強。使用硫酸凝膠態電解質的混合型超級電容器則表現出更好的循環穩定性。研究結果闡明了凝膠電解質和電極材料之間的相互作用，為高性能混合型超級電容器的設計和優化提供了見解[1]。

This study utilized screen printing technology to deposit a nanocomposite precursor of reduced graphene oxide (rGO) and lithium manganese oxide (LiMnOx) on a carbon cloth substrate. Subsequently, a rapid (<300 seconds) annealing process was carried out using nitrogen atmospheric-pressure plasma jet (APPJ). Three gel electrolytes, H2SO4/PVA, LiCl/PVA, and Li2SO4/PVA, were then employed to prepare hybrid supercapacitors (HSCs) featuring the rGO-LiMnOx nanocomposite electrode. The impact of different plasma treatment times was compared by surface analyses and electrochemical measurements, and the influence of the three gel electrolytes on electrode performance was investigated. The compatibility between electrode materials and electrolytes in hybrid supercapacitors was assessed based on electrochemical analyses, including areal capacitance, energy density, and cyclic stability, along with the electrolyte's performance characteristics. The study revealed that plasma treatment significantly improved the performance of the HSC. Among the prepared HSCs, the use of Li2SO4 gel electrolyte exhibited the best areal capacitance and energy density values. This situation arises from its high pseudocapacitance (PC) effect and lithium-ion migration rate, enhancing the electrode-electrolyte interface reactions and effective surface area. Furthermore, the coupling of embedded lithium ions with the electric double-layer capacitance (EDLC) further promotes a significant enhancement of overall capacitance. The HSC employing H2SO4 gel electrolyte also demonstrated improved cyclic stability. The research findings elucidate the interactions between gel electrolytes and electrode materials, providing insights for the design and optimization of high-performance HSCs[1].