Xie Yuming, Li Jingqiu, Cao Mengjue, Feng Yi, Yao Jianfeng
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
Jiangsu Co-Innovation Center of Efficient Processing and Utilization of Forest Resources, College of Chemical Engineering, Nanjing Forestry University, Nanjing 210037, China.
J Colloid Interface Sci. 2023 Jan;629(Pt A):786-793. doi: 10.1016/j.jcis.2022.08.140. Epub 2022 Aug 28.
CoS/Co-Ni layered double hydroxides (LDHs) with a rational tailored pore structure are developed by partial sulfurization of Co-ZIF-L and subsequent Ni etching for the transformation of zeolitic imidazolate frameworks (ZIFs) to layered double hydroxides. The as-synthesized CoS/Co-Ni LDHs maintain the leaf-like structure and have rich hierarchical pores. More importantly, CoS nanoparticles are uniformly embedded among Co-Ni LDH layers, facilitating mass diffusion and favorably exposing more active sites. Benefiting from these desirable compositional and structural features, a remarkable specific capacitance (capacity) of 1784 F/g (223 mAh/g) at 1 A/g is delivered by CoS/Co-Ni LDHs. Furthermore, the as-assembled CoS/Co-Ni LDH//activated carbon as the asymmetric supercapacitor device also exhibits a high energy density of 125 Wh/kg at a power density of 800 W/kg and a superb capacitance retention of 98 % after 5000 cycles, outperforming many Co-Ni LDH based electrode materials reported in the literature.
通过对Co-ZIF-L进行部分硫化以及随后的Ni蚀刻，将沸石咪唑酯骨架（ZIFs）转变为层状双氢氧化物，从而制备出具有合理定制孔结构的CoS/Co-Ni层状双氢氧化物（LDHs）。合成的CoS/Co-Ni LDHs保持叶状结构并具有丰富的分级孔。更重要的是，CoS纳米颗粒均匀地嵌入Co-Ni LDH层之间，促进了质量扩散并有利于暴露更多的活性位点。得益于这些理想的组成和结构特征，CoS/Co-Ni LDHs在1 A/g时具有1784 F/g（223 mAh/g）的显著比电容（容量）。此外，作为不对称超级电容器装置组装的CoS/Co-Ni LDH//活性炭在功率密度为800 W/kg时也表现出125 Wh/kg的高能量密度，并且在5000次循环后具有98%的出色电容保持率，优于文献中报道的许多基于Co-Ni LDH的电极材料。
