Recently, Professor Li Chengchao of our college, taking the school of light industry and chemical engineering of Guangdong University of technology as the first unit, published an independent corresponding author research paper on advanced functional materials (if = 15.621, top journal of zone I).
Lithium ion batteries have been widely used in various portable electronic devices and electric vehicles due to their high working voltage, high energy density and long cycle life.However, the scarcity and cost of lithium resources restrict the application of lithium-ion batteries in large-scale energy storage systems.Compared with lithium, zinc is widely distributed and abundant in the earth's crust, which makes zinc ion battery have obvious resource advantages and price advantages.However, the intercalation and desorption of zinc ions with multivalent electrons in the cathode materials is slow and the dynamic performance is poor, which seriously affects the specific capacity, cycle stability and rate performance of the battery.Therefore, it is still necessary to develop new high performance cathode materials.
In view of this, the team of Professor Li Chengchao of Guangdong University of technology used interlayer manganese ion and water molecular doping to improve the zinc ion transport kinetics of vanadium pentoxide cathode material, and studied its electrochemical zinc storage performance and mechanism as a zinc ion battery cathode material.The results show that the synthesized mn0.15v2o5·nH2O has excellent zinc storage performance, and its reversible capacity is up to 367 MAH g (0.1 AG-1).After 8000 cycles at high current densities of 10 and 20 a g, the specific capacity can still be maintained at 153 and 122 MAHG.Even at the low temperature of - 20 OC, the specific capacity can be stabilized at 100 MAH g at a current density of 2.0 A G for 2000 cycles.The excellent electrochemistry of the material is mainly attributed to the synergistic effect of manganese ions and water molecules, which not only improves the electronic conductivity of the electrode material, but also effectively enhances the insertion and desorption kinetics of zinc ions.Moreover, due to the ion pillaring and local charge interaction, the structural stability of the electrode material in the cycle process is greatly improved.In this work, the phase structure and micro morphology of mnv2o5·nH2O electrode material during charge and discharge were studied by means of in-situ XRD and TEM techniques. The electrochemical zinc storage mechanism was revealed, which provided a basis for the design and synthesis of high rate and long cycle performance cathode materials for zinc ion batteries.The related paper "electronic structure regulation of layered vanadium oxide via interlayer doting strategy towards superior high rate and low temperature zinc ion batteries" was published online on advanced functional materials (DOI: 10.1002 / ADFM. 201907684).-1-1-1-1-10.15
Figure 1. Structure, morphology and electrochemical performance of mnvo·NHO cathode material0.15252