Template-free synthesis of porous V2O5 flakes as a battery-type electrode material with high capacity for supercapacitors

A facile and environment-friendly method was developed to prepare porous V2O5 flakes by the crystallization of ammonium metavanadate (NH4VO3) aqueous solution at 8 degrees C and subsequent calcination in air. The morphologies of the crystallographic NH4VO3 obtained under different vanadium concentrations and crystallization temperatures were characterized by scanning electron microscope (SEM), and a possible growth mechanism was discussed. The impact of the calcination temperatures on the morphologies and electrochemical properties of porous V2O5 flakes was studied. The pores of the obtained V2O5 flakes mainly consist of mesoporous with an average pore size of 28.66 nm. Electrochemical properties of the porous V2O5 flakes as a battery-type electrode were measured. The product exhibited a high capacity of 510 F g(-1) at 0.2 A g(-1) and remained over 110% of the initial capacitance after 1000 cycles. The outstanding electrochemical performance of the porous V2O5 flakes make them promising candidates as a battery-type electrode material for supercapacitors.