Abstract The electrochemical performance of nickel-based modified electrodes deposited on stainless steel from ionic liquid was studied in the positive potential regions of alkaline solution to combine with graphite in the negative potential regions for asymmetric supercapacitor applications. Nickel-based electrodes were electroplated, separately, from an ionic liquid solution containing Ni2+ ions and an aqueous solution (Watts solution). The films obtained from the non-aqueous solutions (ionic liquid) were more stable and had better electrochemical performance than those from Watts solutions. The electrochemical performance, including capacitance, power and stability of electrodes were optimized depending on the deposition conditions, specifically, the electrolyte, deposition potential and deposition times. The performance of electrode may be regulated by altering material structure via the deposition conditions. The rate limiting reaction of nickel electrodes deposited from the ionic liquids was not dependent on deposition potentials and time. It was noted to be the mixture of surface and diffusional control mechanisms. As nickel-based coatings electrodeposited from ionic liquid had high surface area, they may be more suitable for energy storage electrodes than the electrodes obtained from Watts solution. The highest specific capacitance of the prepared nickel electrodes was found to be 1690 F g−1 for the electrode electrodeposited from ionic liquid by the application of -0.7 V for 300 s. Ion transfer reactions between nickel electrodes of porous nanostructures and alkaline electrolyte were fast as a direct result of the greater surface areas.

中文翻译：

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用于不对称超级电容器生产的离子液体电解质镍膜生成电沉积电位和时间的影响

摘要 研究了离子液体沉积在不锈钢上的镍基改性电极在碱性溶液的正电位区与负电位区的石墨结合的电化学性能，用于不对称超级电容器应用。镍基电极分别从含有 Ni2+ 离子的离子液体溶液和水溶液（瓦特溶液）中电镀。从非水溶液（离子液体）获得的薄膜比从瓦特溶液获得的薄膜更稳定，具有更好的电化学性能。根据沉积条件，特别是电解质、沉积电位和沉积时间，优化电化学性能，包括电极的电容、功率和稳定性。电极的性能可以通过沉积条件改变材料结构来调节。从离子液体沉积的镍电极的限速反应不依赖于沉积电位和时间。注意到它是表面和扩散控制机制的混合。由于由离子液体电沉积的镍基涂层具有高表面积，因此与从瓦特溶液获得的电极相比，它们可能更适合用于储能电极。对于通过施加-0.7 V 300 秒从离子液体电沉积的电极，发现制备的镍电极的最高比电容为1690 F g-1。由于更大的表面积，多孔纳米结构的镍电极和碱性电解质之间的离子转移反应很快。