1] School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore [2] College of Material Science and Engineering, Nanjing University of Aeronautics and Astronautics, Nanjing 210016, China.
School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, Singapore 637459, Singapore.
Nat Commun. 2015 Mar 23;6:6694. doi: 10.1038/ncomms7694.
While the synthesis of hollow structures of transition metal oxides is well established, it is extremely challenging to fabricate complex hollow structures for mixed transition metal sulfides. Here we report an anion exchange method to synthesize a complex ternary metal sulfides hollow structure, namely nickel cobalt sulfide ball-in-ball hollow spheres. Uniform nickel cobalt glycerate solid spheres are first synthesized as the precursor and subsequently chemically transformed into nickel cobalt sulfide ball-in-ball hollow spheres. When used as electrode materials for electrochemical capacitors, these nickel cobalt sulfide hollow spheres deliver a specific capacitance of 1,036 F g(-1) at a current density of 1.0 A g(-1). An asymmetric supercapacitor based on these ball-in-ball structures shows long-term cycling performance with a high energy density of 42.3 Wh kg(-1) at a power density of 476 W kg(-1), suggesting their potential application in high-performance electrochemical capacitors.
虽然过渡金属氧化物的中空结构的合成已经得到很好的建立，但对于混合过渡金属硫化物来说，制造复杂的中空结构极具挑战性。在这里，我们报告了一种阴离子交换方法来合成一种复杂的三元金属硫化物中空结构，即镍钴硫化物球中球中空球。首先合成均匀的镍钴甘油酸盐固体球作为前体，然后将其化学转化为镍钴硫化物球中球中空球。当用作电化学电容器的电极材料时，这些镍钴硫化物中空球在 1.0 A g-1 的电流密度下表现出 1036 F g-1 的比电容。基于这些球中球结构的非对称超级电容器具有长循环性能，在 476 W kg-1 的功率密度下具有 42.3 Wh kg-1 的高能量密度，表明其在高性能电化学电容器中的潜在应用。
