In the last years, supercapacitors (SCs) have been proposed as a promising alternative to cover the power density deficiency presented in batteries. Electrical double-layer SCs, pseudocapacitors, and hybrid supercapacitors (HSCs) have shown very attractive features such as high-power density, long cycle life, and tunable specific capacitance. The advances of these energy storage devices made by transition metal oxides (TMOs) and their production in pseudocapacitors and HSCs depend on chemical composition, crystalline structure, morphology, theoretical capacitance, and oxidation states. In this way, this critical review considers several metal oxides (RuO 2 , MnO 2 , V 2 O 5 , and Co 3 O 4 ) and their different configurations with diverse carbon-based materials. Energy storage mechanisms and fundamental principles to understand the promising effect of metal oxides in SCs devices are thoroughly described. Special attention as regards to the energy storage mechanisms relative to the specific capacitance values is presented in the reviewed articles. This review envisages the TMO as a key component to obtain high specific capacitance SCs.

中文翻译：

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过渡金属氧化物基超级电容器的设计与应用进展

在过去几年中，超级电容器 (SC) 已被提议作为一种有前景的替代品，以弥补电池中存在的功率密度不足。双电层 SC、赝电容器和混合超级电容器 (HSC) 已显示出非常有吸引力的特性，例如高功率密度、长循环寿命和可调比电容。这些由过渡金属氧化物 (TMO) 制成的储能装置的进展及其在赝电容器和 HSC 中的生产取决于化学成分、晶体结构、形态、理论电容和氧化态。通过这种方式，本次批判性评论考虑了几种金属氧化物（RuO 2 、MnO 2 、V 2 O 5 和 Co 3 O 4 ）及其与不同碳基材料的不同配置。详细描述了能量存储机制和基本原理，以了解金属氧化物在 SCs 器件中的前景。评论文章中特别关注了与特定电容值相关的能量存储机制。该评论将 TMO 视为获得高比电容 SC 的关键组件。