Microwave-assisted Synthesis Of Bimetal Oxide/Hydroxide And Their Application In Supercapacitors

The rapid consumption of fossil fuels and the resulted environmental pollution have become one of the most important issues in the world,so the search for sustainable energy sources and advanced energy conversion and storage techniques has become an urgent need for scientists around the world.Supercapacitors have the advantages of fast charge-discharge rate,long lifecycle,low maintenance cost and high power density.The key to advance the application of supercapacitors lies in the development of excellent electrode materials with the lowest environmental cost.At present,a variety of materials have been studied for electrode materials for supercapacitors.This paper focuses on the application of molybdenum-based metal oxides and layered bimetal hydroxide electrode materials in supercapacitors.MnMoO4 and NiCo-LDH were prepared by microwave hydrothermally assisted method and their pseudo capacitance properties were studied.(1)Microwave-assisted hydrothermal method and subsequent calcining process were used to prepare ?-MnMoO4 nanorods.The effects of microwave reaction time on the structure and morphology of ?-MnMoO4 crystals were investigated.The results show that the microwave reaction time has no effect on the structure of the product,but has some effect on its morphology.Thorough characterization of the electrochemical properties was performed,and the results demonstrated the extraordinary supercapacitor properties with a high specific capacitance(446.7 F g-1 at current densities of 1 mA cm-2),excellent rate capability,and superior cycling stability(81.12%retained after 3000 cycles at 8 mA cm-2).(2)The NiCo-LDH microsphere with high stability was synthesized rapidly under microwave-assisted conditions,and the effects of microwave reaction time on the crystal structure and morphology of NiCo-LDH were investigated.The results show that the crystal has a directional growth process,and with the increase of reaction time,the morphology of crystal had changed.The electrochemical test showed that the specific capacitance of the LDH-10 electrode reached 741.67 F g-1 at 1 mA cm-2.At the same time,under the condition of current density of 6 mA cm-2,the capacitance can still maintain 86.81%of the original capacitance after 3000 cycles.Compared with the single hydroxide electrode,the electrochemical performance of NiCo-LDH electrode had improved.