Tungsten Oxide Quantum Dot Materials

Tungsten Oxide Quantum Dot Materials Making Progress

Emerging energy conversion and storage devices, such as lithium-ion batteries, super capacitors, fuel cells have shown great potential in solving the issues of traditional energy shortage, instable of renewable energy sources, and been widely concerned in the academia and industry.

Zhigang Zhao Research Group of Suzhou Institute of Nano researchers and Professor FengXia Geng Group of Suzhou University have been detailed and in-depth research for this issue, and have breakthrough on the research of preparation and application of electrochemical oxidation of tungsten quantum dot. They use tungsten metal organic complexes as precursors, single fatty amine reactant/solvent, to obtain WO₃-x nano-crystals with uniform size, the average particle diameter of only 1.6 nm and can dispersed in an organic solvent, also strong quantum size effects have been observed, which have solved the problems of hard to obtain of tungsten oxide quantum dots, or the preparation process must rely on the lattice template (silica gel, molecular sieve).

The quantum dots exhibit outstanding electrochemical properties when the researchers further changed long chain fatty amine to pyridine molecule which coating the quantum dots by a simple ligand exchange method. The discharge and electrochromic test results showed that: (1) CV peak and fine structure still maintain at a high scan rate of 500 mV/s, and performance of high rate magnification; (2) The time of chromophore and fade are within 1s, the discoloration efficiency can up to 154 cm2/C, which the performance is better than none-zero-dimensional tungsten oxide and other inorganic electroluminescent material.

This work confirmed that the transfer processes of substance and electric charge will be greatly enhanced after the particle scale of conventional electrode material is reduced to zero-dimensional, and it is expected that quantum dot material can be expanded to the application of ultra-fast response electrochemical device.