Search Results
Now showing 1 - 2 of 2
- In this study, a facile and potentially scalable synthesis of AgBiS2 (schapbachite) using melts of metal xanthates is presented; AgBiS2 is both a significant mineral and a technologically important material. This ternary material was synthesized by a novel and low-cost solventless route using simple ethyl xanthate complexes of silver and bismuth. p-XRD analysis indicates that the synthesized ternary material is highly crystalline and belongs to the cubic phase (schapbachite). The electrochemical properties of the material were tested; the potential of the synthesized material for application in charge storage shows a high specific capacitance of 460 F g−1 at 2 mV s−1. A capacitance retention of 83% with a 100% coulombic efficiency was observed after 3000 cycles. The charge storage potential, analysed by fabricating actual symmetrical devices, shows a specific capacitance of 14 F g−1 at 2 mV s−1. An energy density of 26 W h kg−1 and a power density of 3.6 kW kg−1 were observed. Besides, the potential for the oxygen evolution reaction was also studied. An overpotential of 414 mV and a Tafel slope of 134 mV dec−1 were obtained for water oxidation. The fabrication of an electrolyzer cell using the synthesized material as the cathode indicates that a current of 10 mA cm−2 can be achieved at a potential of 1.63 V.
- 1
- 3
- 0
- The development of cost‐effective and easily accessible bifunctional materials, which can be effectively used for energy storage and energy generation, is highly desirable. Herein, a new molecular precursor [tris(morpholinodithiocarbamato)Co(III)] has been synthesized and the X‐ray crystal structure of the complex determined. The precursor was used to prepare oleylamine (OLA)‐capped cobalt sulfide nanoplatelets, using a facile hot injection method at two different temperatures (200 °C and 260 °C). The characterization of the samples shows that CoS synthesized at 200 °C is slightly sulfur rich, whereas CoS synthesized at 260 °C is slightly cobalt rich. The effect of off‐stoichiometry of CoS nanoplatelets on the energy generation and storage applications was studied. The oxygen evolution reaction catalytic performance of both samples indicate overpotentials of 307 and 276 mV as well as Tafel slopes of 96 and 82 mV/dec, respectively. Similarly, overpotentials of 132 and 153 mV were observed for the hydrogen evolution reaction, with Tafel slopes of 159 and 154 mV/dec, respectively. The capacitive behavior of the samples was also examined, and specific capacitance values of 298 and 440 F/g were obtained with cycling stabilities of 73 and 97 %, after 5000 cycles, respectively. The results indicate that sulfur‐deficient CoS can show superior performance for efficient energy generation and storage devices.
- 1
- 3
- 0