Powder Technology, Vol.309, 22-30, 2017
Low-temperature synthesis of two-dimensional nanostructured Co3O4 and improved electrochemical properties for lithium-ion batteries
Urea as a cheap reagent is very useful in preparation two-dimensional metal oxides with tunable crystal morphologies, while refluxing method is a simple route to control the decomposition of urea. Here, a low temperature refluxing in the presence of urea is developed to prepare porous Co3O4 as anode material for lithium-ion batteries. The self-assembly cobalt hydrotalcite-like compounds (Co-HLC) is firstly synthesized through refluxing the mixture of cobaltous nitrate and urea. After pyrolysis, the flower-like morphology of Co-HLC is successfully maintained in the final product of Co3O4. The ordered two-dimensional Co3O4 nanosheets provide good Contact with electrolyte and stable porous structure during lithiation/delithiation. Co3O4-120 synthesized tinder refluxing temperature of 120 degrees C shows the initial charge capacities of 722 and 741 mAh g(-1) at the 2nd and 100th cycle under 100 mA g(-1). Moreover, Co3O4-120 as electrode for a supercapacitor presents excellent capacitance, 167 F g(-1), after 3000 cycles at 1 A g(-1). Under 5, 10 and 20 A Co3O4-120 electrode delivers 128,104 and 90 F g(-1), respectively. The porous structure in Co3O4 with enhanced electrochemical performance indicates low temperature refluxing preparation is an applicable and energy-saved method to synthesize transitional metal oxide with tunable crystal morphologies. (C) 2016 Elsevier B.V. All rights reserved.