Abstract In this work, we have fabricated high-performance thin-film electrodes for electrochemical capacitors (ECs) via thermal decomposition syntheses of RuO2–Ta2O5 coating layers on Ti substrates. The influences of decomposition temperature as well as the Ru/Ta molar ratio on material and electrochemical properties of the EC electrodes are systematically investigated. The thermal decomposition of 300 °C preserves a large fraction of hydrous RuO2·xH2O within the hybrid oxide and consequently improves the electrode capacitance. The amorphous Ta2O5 incorporation can manipulate the RuO2 crystallinity and thus its specific capacitance. An optimal Ru/Ta molar ratio of 7:3 is determined for the RuO2–Ta2O5 electrode, which can deliver an energy density of 4.8 Wh kg−1 at a power density of 8,720 W kg−1 (or 8.3 Wh L−1 at 15,000 W L−1). In addition, an excellent durability of 97.6% capacitance retention after 3,000 charge-discharge cycles is found for this electrode. The proposed RuO2–Ta2O5 thin-film electrode has paved the way for next-generation ECs with superior capacitances, energy/power densities, and cyclability.

中文翻译：

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电化学电容器用热分解法制备的水合氧化钌-五氧化二钽薄膜电极

摘要 在这项工作中，我们通过在 Ti 基板上热分解合成 RuO2–Ta2O5 涂层，制备了用于电化学电容器 (ECs) 的高性能薄膜电极。系统地研究了分解温度以及 Ru/Ta 摩尔比对 EC 电极材料和电化学性能的影响。300 °C 的热分解在混合氧化物中保留了大部分水合 RuO2·xH2O，从而提高了电极电容。无定形 Ta2O5 的掺入可以控制 RuO2 的结晶度，从而控制其比电容。RuO2–Ta2O5 电极的最佳 Ru/Ta 摩尔比确定为 7:3，在 8,720 W kg-1 的功率密度下（或 8.3 Wh L-1 的功率密度），该电极可以提供 4.8 Wh kg-1 的能量密度。 15,000 WL-1）。此外，发现该电极在 3,000 次充放电循环后具有 97.6% 的优异耐久性。所提出的 RuO2-Ta2O5 薄膜电极为具有优异电容、能量/功率密度和循环性的下一代 ECs 铺平了道路。