摘要
Highly cross-linked porous NiCo2S4 nanosheets arrays are synthesized by a high-efficiency hydrothermal conversion from the preformed electrodeposited NiCo2O4 arrays. By using thioacetamide as the sulfur source, the electrodeposited NiCo2O4 is directly converted into NiCo2O4 nanosheets arrays without hightemperature sulfurization. Higher porosity and better electrical conductivity are obtained for the NiCo2O4 nanosheets arrays. In addition, reduced diffusion paths of electrons/ions and alleviated volume expansion during cycling are achieved due to the unique porous structure of NiCo2S4. Consequently, as the cathode of alkaline batteries, the obtained NiCo2S4 nanosheets arrays show better electrochemical performance with a high specific capacity(83.5 m Ah g-1 at 0.5 A g-1) and better cycling stability(capacity retention of 93% after 5000 cycles) than the NiCo2O4 counterpart arrays(40.3 mAh g-1 at 0.5 A g-1). Our work demonstrates that sulfurization on binary metal oxides can greatly enhance electrochemical performance and shows a new way for construction of advanced electrodes for high-rate batteries.
Highly cross-linked porous NiCo2S4 nanosheets arrays are synthesized by a high-efficiency hydrothermal conversion from the preformed electrodeposited NiCo2O4 arrays. By using thioacetamide as the sulfur source, the electrodeposited NiCo2O4 is directly converted into NiCo2O4 nanosheets arrays without hightemperature sulfurization. Higher porosity and better electrical conductivity are obtained for the NiCo2O4 nanosheets arrays. In addition, reduced diffusion paths of electrons/ions and alleviated volume expansion during cycling are achieved due to the unique porous structure of NiCo2S4. Consequently, as the cathode of alkaline batteries, the obtained NiCo2S4 nanosheets arrays show better electrochemical performance with a high specific capacity(83.5 m Ah g-1 at 0.5 A g-1) and better cycling stability（capacity retention of 93% after 5000 cycles） than the NiCo2O4 counterpart arrays(40.3 mAh g-1 at 0.5 A g-1). Our work demonstrates that sulfurization on binary metal oxides can greatly enhance electrochemical performance and shows a new way for construction of advanced electrodes for high-rate batteries.
基金
financial support from National Natural Science Foundation of China(Grant No.51502188)
Science and Technology Program of Taizhou(Grant No.14GY03)
Excellent Young Scientists Fund of Taizhou University(Grant No.2017JQ004)
supported by National Natural Science Foundation of China(Grant No.51772272,51502263 and 51728204)
Fundamental Research Funds for the Central Universities(Grant No.2018QNA4011)
Qianjiang Talents Plan D(QJD1602029)
Startup Foundation for Hundred-Talent Program of Zhejiang University
