In this work, we studied the effect of adding a redox electrolyte on the specific capacitance of SrRuO₃–reduced graphene oxide (SRGO) nanocomposite electrode. Two redox systems were considered, quinone/hydroquinone and triiodide/iodide (I₃^–/I^–) in acidic (H₃PO₄) and neutral (NaNO₃) solutions. The employment of reduced graphene oxide reduces the amount of Ru loading to the surface down to 20% to achieve a specific capacitance (C_s) of 62.4 F·g^–1 in 1.0 M NaNO₃ and 101 F·g^–1 in 1.0 M H₃PO₄. The C_s of the electrode increased by 21.6 folds in KI-containing NaNO₃ solutions compared with the NaNO₃ electrolyte. The presence of the redox system in the electrolyte enhanced the cycling stability of the electrode to 173% compared with its initial value after 1000 galvanic charging/discharging (GCD) cycles compared with 93% in its absence. The presence of redox-intermediates including iodine (I₂) participate in the surface reaction and contribute to the observed enhancement in both C_s and cycling GCD. A maximum C_s value of 1037 F·g^–1 (733 mF·cm^–2) at 5 A·g^–1 was obtained by using SRGO/0.08 M KI–1.0 M NaNO₃.

中文翻译：

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氧化还原电解质对SrRuO ₃还原氧化石墨烯纳米复合材料比电容的影响

在这项工作中，我们研究了添加氧化还原电解质对SrRuO ₃还原氧化石墨烯（SRGO）纳米复合电极的比电容的影响。考虑了两种氧化还原体系，分别是在酸性（H ₃ PO ₄）和中性（NaNO ₃）溶液中的醌/氢醌和三碘化物/碘化物（I ₃ ^– / I ^–）。使用还原的氧化石墨烯可使表面上的Ru负载量降低至20％，以在1.0 M NaNO _3中获得62.4 F·g ^–1的比电容（C _s）在1.0 MH中获得101 F·g ^–1的比电容₃ PO ₄。这与含NaNO _3的电解质相比，在含KI的NaNO ₃溶液中电极的C _s增加了21.6倍。电解质中氧化还原体系的存在与其在1000次电流充电/放电（GCD）循环后的初始值相比，将电极的循环稳定性提高到173％，而在不存在电极的情况下，则提高了93％。包括碘（I ₂）在内的氧化还原中间体的存在参与了表面反应，并有助于观察到的C _s和循环GCD的增强。最多Ç_小号的1037·F·G值^-1（733μF的·厘米^-2 5 A）·克^-1通过使用SRGO / 0.08 M KI–1.0 M NaNO _3获得。