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arXiv · 1910.03813

Surface-charge-mediated Formation of H-TiO2@Ni(OH)2 Heterostructures for High-Performance Supercapcitors

Qingqing Ke·Cao Guan·Xiao Zhang·Minrui Zheng·Yong-Wei Zhang·Yongqing Cai·Hua Zhang·John Wang
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Abstract

Supercapacitors or ultracapacitors are promising for efficient energy storage applications, owing to their high power density, high charge-discharge rates, and long cycle life performance. To achieve this goal, a large specific surface area, an high electronic conductivity and a fast cation intercalation de-intercalation process are generally required in the design and preparation of materials for high-performance supercapacitors. Recently, core-shell heterostructures with multifunctionalities are regarded as one of promising materials for supercapacitors or ultracapacitors applications. In particular, one-dimensional (1D) core-shell heterostructures have sparked great scientific and technological interests due to their high versatility and applicability as the essential components in nanoscale electronics, catalysis, chemical sensing, and energy conversion storage devices. Various metal metal oxide, metal metal, metal oxide metal oxide and metal oxide conductive polymers so far have been investigated. Transition metal hydroxide oxide Co3O4, Co(OH)2, MnO2, Mn(OH)2, NiO, Ni(OH)2 and their compounds storing energy by surface faradaic (redox) reactions were generally integrated with conducting scaffold to build core-shell structure. Intensive studies show that an enlarged active surface area of transition metal hydroxide oxide enables a promoted surface redox reaction and enhanced electrochemical performance. Therefore, controllable synthesis of a hierarchically porous construction with high surface areas is critically important for energy storage.

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Qingqing Ke, Cao Guan, Xiao Zhang, Minrui Zheng, Yong-Wei Zhang, Yongqing Cai, Hua Zhang, John Wang. 2019-10-09. Surface-charge-mediated Formation of H-TiO2@Ni(OH)2 Heterostructures for High-Performance Supercapcitors. https://arxiv.org/abs/1910.03813

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