Zhang Panpan, Wang Mingchao, Liu Yannan, Fu Yubin, Gao Mingming, Wang Gang, Wang Faxing, Wang Zhiyong, Chen Guangbo, Yang Sheng, Liu Youwen, Dong Renhao, Yu Minghao, Lu Xing, Feng Xinliang
State Key Laboratory of Materials Processing and Die & Mould Technology, School of Materials Science and Engineering, Huazhong University of Science and Technology, 430074 Wuhan, China.
Center for Advancing Electronics Dresden (cfaed) and Faculty of Chemistry and Food Chemistry, Technische Universität Dresden, Mommsenstr. 4, 01062 Dresden, Germany.
J Am Chem Soc. 2023 Mar 22;145(11):6247-6256. doi: 10.1021/jacs.2c12684. Epub 2023 Mar 9.
Although two-dimensional conjugated metal-organic frameworks (2D -MOFs) provide an ideal platform for precise tailoring of capacitive electrode materials, high-capacitance 2D -MOFs for non-aqueous supercapacitors remain to be further explored. Herein, we report a novel phthalocyanine-based nickel-bis(dithiolene) (NiS)-linked 2D -MOF (denoted as Ni[CuPcS]) with outstanding pseudocapacitive properties in 1 M TEABF/acetonitrile. Each NiS linkage is disclosed to reversibly accommodate two electrons, conferring the Ni[CuPcS] electrode a two-step Faradic reaction with a record-high specific capacitance among the reported 2D -MOFs in non-aqueous electrolytes (312 F g) and remarkable cycling stability (93.5% after 10,000 cycles). Multiple analyses unveil that the unique electron-storage capability of Ni[CuPcS] originates from its localized lowest unoccupied molecular orbital (LUMO) over the nickel-bis(dithiolene) linkage, which allows the efficient delocalization of the injected electrons throughout the conjugated linkage units without inducing apparent bonding stress. The Ni[CuPcS] anode is used to demonstrate an asymmetric supercapacitor device that delivers a high operating voltage of 2.3 V, a maximum energy density of 57.4 Wh kg, and ultralong stability over 5000 cycles.
尽管二维共轭金属有机框架（2D-MOFs）为电容性电极材料的精确剪裁提供了理想平台，但用于非水系超级电容器的高电容2D-MOFs仍有待进一步探索。在此，我们报道了一种新型的基于酞菁的镍双（二硫纶）（NiS）连接的2D-MOF（表示为Ni[CuPcS]），其在1 M四乙基铵四氟硼酸盐/乙腈中具有出色的赝电容性能。据揭示，每个NiS连接可可逆地容纳两个电子，赋予Ni[CuPcS]电极两步法拉第反应，在报道的非水电解质中的2D-MOFs中具有创纪录的高比电容（312 F/g）和出色的循环稳定性（10000次循环后为93.5%）。多项分析表明，Ni[CuPcS]独特的电子存储能力源于其在镍双（二硫纶）连接上的局域最低未占分子轨道（LUMO），这使得注入的电子能够在整个共轭连接单元中高效离域，而不会产生明显的键合应力。Ni[CuPcS]阳极用于展示一种不对称超级电容器装置，该装置具有2.3 V的高工作电压、57.4 Wh/kg的最大能量密度以及超过5000次循环的超长稳定性。
