Phosphotungstate (H3PW12O40) is a kind of heteropolyacid polymetallic oxygen cluster. Phosphotungstate is a well-studied positive electrode active material in heteropolyacid molecular clusters. Due to its reversible multi-electron redox reaction, it has It can achieve a high specific capacity of 260Ah/kg and excellent performance of rapid charge and discharge, and its capacity exceeds the 150Ah/kg of the commercialized common Li2CoO2 lithium-ion battery.
Phosphotungstate has excellent electrochemical properties: it can reversibly gain or lose one or more electrons while keeping its structure unchanged. Because of the electron transfer form of heteropolyacid, the polyaniline-phosphotungstic acid microsphere composite material wrapped in poly three-dimensional graphene has excellent charge and discharge performance as the active material of the positive electrode material of the battery. However, lithium ions intercalate and deintercalate into the microcrystalline structure of heteropolyacids and the rough electron transfer channels of heteropolyacids, so the conductivity of pure heteropolyacids is poor, which is close to that of insulators.
In order to solve the above problems, the researchers designed a graphene-polyaniline-phosphotungstic acid composite material. The composite material is composed of polyaniline and phosphotungstic acid self-assembled into microspheres and then loaded onto three-dimensional graphene, which includes Follow the steps below:
- Dissolve a certain amount of phosphotungstic acid in a mixed solution of water and concentrated sulfuric acid, add polyaniline and stir for a period of time, let it stand in an ice bath, and centrifugally dry to obtain polyaniline-tungstic acid microspheres;
2) Ultrasonic disperse the polyaniline/phosphotungstic acid microspheres in a small amount of water to make an aqueous solution, then add it to the graphene oxide aqueous solution, stir evenly and perform a hydrothermal reaction, cool to room temperature after the reaction, and take out the solid aggregate , freeze-dried to obtain the three-dimensional graphene-aniline-tungstic acid composite material. This synthetic material can be used as a cathode material for lithium-ion batteries.
Studies have shown that the three-dimensional graphene-polyaniline-phosphotungstic acid composite material not only solves the problem of difficult intercalation and extraction of lithium ions in the microcrystalline structure, but also greatly increases its conductivity, and has good cycle reversibility and stability. It is used as the positive electrode material of lithium-ion batteries, which can improve the conductivity of heteropolyacid molecular cluster batteries.
More details of tungstic acid product, please visit website: tungstic-acid.com
Please contact CHINATUNGSTEN for inquiry and order of tungstic acid:
Email: sales@chinatungsten.com
Tel.: 86 592 5129595
