Introduction to the results
Inspired by agricultural ridge technology, this article, Jiangsu University of Science and TechnologyAssociate Professor Guo Xingmei, Professor Zhang Junhao, Professor Shenglin of Shandong University and other researchers published the title "Growing Co-Ni" in the journal "Inorg. Chem. Front" -Se nanosheets on 3D carbon frameworks as advanced dual functional electrodes for supercapacitors and sodium ion batteries” paper, Research proposes a facile strategy to prepare butterfly wing-derived carbon through microwave precipitation, ion exchange, chemical etching and hydrothermal methods Cobalt nickel selenium (Co-Ni-Se) nanosheets grown on framework (BWCF). selenization process. BWCF has a unique three-dimensional porous structure with parallel ridges and numerous hole arrays, similar to the ditches and ridges of farmland. Ni-Co-Se nanosheets are uniformly and firmly anchored on BWCF, similar to crops grown in furrows, which can prevent the agglomeration and shedding of active materials, thereby effectively improving structural stability.
Based on the special hierarchical structure and synergistic effect of bimetallic selenide, the synthesized Ni-Co-Se/BWCF shows excellent electrochemical performance as a self-supporting electrode in SIBs and SCs. When it was assembled into the supercapacitor , a high capacity of 3050Fg-1 was obtained at 1.0Ag-1, and it retained 1006Fg-1 at 20A g-1. Asymmetric supercapacitor based on Co-Ni-Se/BWCF-160 and a-BWC achieves a high energy density of 49.7 W h kg at 1052 W kg and is retained after 5000 cycles at 10 A g The rate is 93.3%. When Co-Ni-Se/BWCF-160 is assembled as a SIB anode, the initial discharge specific capacity is as high as 703 mA hg -1 at 0.1 A g -1 and remains 403 mA hg -1 after 100 cycles. This work inspires us because nature has rich hierarchical structures that can be imitated to construct electrode materials with excellent electrochemical properties.
Graphic and text introduction
Figure 1. Schematic diagram of the preparation route and application of Co-Ni-Se/BWCF.
Figure 2. FESEM images of samples: (a-c) Co-MOF/BWCF; (d-f) Co-Ni-OH/BWCF; (g-i) Co-Ni-Se/BWCF-160.
Figure 3. CV curve; (c) GCD curve of Co-Ni-Se/BWCF-160 in the range of 1 to 20Ag-1; (d) log( i ) and log( v ) of Co-Ni-Se/BWCF-160 Plot; (e) Separation of capacitive current and diffusion-controlled current at 20 mV s -1; (f) Normalized percentage of capacitive contribution at different scan rates.
Figure 5. Electrochemical properties
Summary
In summary, Ni-Co-Se/BWCF-160 was prepared through microwave precipitation, ion exchange, chemical etching and hydrothermal selenization process. Co-Ni-Se nanosheets are uniformly dispersed and firmly anchored on BWCF. The nanosheet structure of Ni-Co-Se is conducive to exposing redox active sites, and the ordered hole array ensures that the electrolyte fully wets the electrode material. In addition, this structure makes the ion/electron transfer and diffusion between BWC and Co-Ni-Se more efficient, accelerating the electrochemical reaction kinetics.
Literature:
https://doi.org/10.1039/D2QI00695B
