這項研究探討了鈷摻雜二氧化錳(Co-doped MnO2)電極在硫酸鎂(MgSO4)電解質中的增強擬電容性能，應用於高性能超級電容器。鈷摻雜二氧化錳電極通過水熱法合成，形成具有層次化微花形態與2 × 2隧道結構。該結構顯著提高了材料的比表面積，達到158 m2 g-1，相比之下，未摻雜鈷的二氧化錳僅為80 m2 g-1。

電化學性能評估，包括循環伏安法(CV)和恒電流充放電(GCD)，在硫酸鎂電解質中表現出顯著成果。鈷摻雜二氧化錳電極在1 A g-1的電流密度下實現了527 F g-1的顯著比電容，這比在硫酸鈉(Na2SO4)電解質中實現的電容高出1.6倍。性能提升歸因於鈷摻雜的協同效應和鎂離子在電解質中有效的電子供應。

通過X射線繞射(XRD)、X射線光電子能譜(XPS)、比表面積分析(BET)和掃描式電子顯微鏡(SEM)等鑑定技術，進一步確認了鈷摻雜二氧化錳電極的結構和組成優勢。

研究結論表明，鈷摻雜二氧化錳電極並使用硫酸鎂作為電解質，顯著提升了電極的電化學性能和循環穩定性，彰顯其在新一代超級電容器中的潛力。

This study investigates the pseudocapacitive enhancement of cobalt-doped manganese oxide (Co-doped MnO2) electrode in magnesium sulfate (MgSO4) electrolyte for high-performance supercapacitors. Co-doped MnO2 electrode was synthesized using a hydrothermal process, resulting in a 2 × 2 tunnel structure with a hierarchical micro-flower morphology.

This structure significantly increases the material’s specific surface area to 158 m2 g-1, compared to the bare MnO2’s 80 m2 g-1. Electrochemical performance evaluation, including cyclic voltammetry (CV) and galvanostatic charge-discharge (GCD), reveals significant results in a magnesium sulfate electrolyte. The Co-doped MnO2 electrode achieved a notable specific capacitance of 527 F g-1 at a current density of 1 A g-1 in MgSO4 electrolyte.

This capacitance is 1.6 times higher than that achieved in Na2SO4 electrolyte. The enhanced performance is attributed to the synergistic effects of cobalt doping and the effective electron donation from magnesium ions in the electrolyte. Characterization techniques such as X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), Brunauer-Emmett-Teller (BET) surface area analysis, and scanning electron microscopy (SEM) further confirm the structural and compositional advantages of the Co-doped MnO2.

The study concludes that the incorporation of Co into MnO2 and the use of MgSO4 as an electrolyte substantially improve the electrochemical properties and cycling stability of the electrode, underscoring their potential for next-generation supercapacitors.

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