Abstract Dodecahedral imidazolium framework-67 (ZIF-67) is synthesized in aqueous solution and used as a sacrificial template for the synthesis of uniform three-dimensional (3-D) hierarchical hexagonal flower-like nickel–cobalt layered double hydroxides (NiCo-LDH) by facile hydrothermal treatment. TEM and SEM results reveal that each microflower is composed of abundant two-dimensional (2D) ultrathin wrinkled nanosheets. The induction of 2,3,5,6-terafluroterephthalic acid (H2tfbdc) and hexamethylenetetramine (HMT) as an additive along with nickel nitrate hexahydrate plays a vital role to tune uniform hierarchical morphology and augmented electrochemical performance. The supercapacitor performance results show that (NiCo-LDH)SHH electrode has the best supercapacitor performance when it is used as a pseudo-capacitor. The maximum specific capacitance is 1765 F g−1 at the current density of 1 A g−1 with stable cycling performance. An asymmetric supercapacitor device assembled using (NiCo-LDH)SHH as the positive and activated carbon (AC) as the negative electrode attains a high energy density of 53.31 Wh kg−1 at a power density of 749.7 W kg−1 with 84.3% capacitance retention after 6000 cycles. This work provides a novel route for the design and synthesis of two-component hydrotalcite with 2D nanosheets having a large interlayer spacing of 9.3 d(A) and its potential application in electrochemical energy storage.

中文翻译：

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使用二元添加剂合成由 ZIF-67 衍生的形态受控的 NiCo-LDH 微花及其优异的不对称超级电容器性能

摘要 十二面体咪唑鎓骨架-67 (ZIF-67) 在水溶液中合成，并用作合成均匀三维 (3-D) 分层六方花状镍钴层状双氢氧化物 (NiCo-LDH) 的牺牲模板。 ) 通过简单的水热处理。TEM 和 SEM 结果表明，每个微花由丰富的二维 (2D) 超薄皱纹纳米片组成。2,3,5,6-四氟对苯二甲酸（H2tfbdc）和六亚甲基四胺（HMT）作为添加剂与六水合硝酸镍的诱导对于调节均匀的分级形态和增强的电化学性能起着至关重要的作用。超级电容器性能结果表明，(NiCo-LDH)SHH电极作为伪电容器具有最佳的超级电容器性能。在电流密度为 1 A g-1 时，最大比电容为 1765 F g-1，循环性能稳定。使用 (NiCo-LDH)SHH 作为正极和活性炭 (AC) 作为负极组装的非对称超级电容器装置在 749.7 W kg-1 的功率密度和 84.3% 的电容下获得了 53.31 Wh kg-1 的高能量密度6000 次循环后的保持率。这项工作为设计和合成具有 9.3 d(A) 大层间距的二维纳米片的双组分水滑石及其在电化学储能中的潜在应用提供了新途径。31 Wh kg-1，功率密度为 749.7 W kg-1，6000 次循环后电容保持率为 84.3%。这项工作为设计和合成具有 9.3 d(A) 大层间距的二维纳米片的双组分水滑石及其在电化学储能中的潜在应用提供了新途径。31 Wh kg-1，功率密度为 749.7 W kg-1，6000 次循环后电容保持率为 84.3%。这项工作为设计和合成具有 9.3 d(A) 大层间距的二维纳米片的双组分水滑石及其在电化学储能中的潜在应用提供了新途径。