 |
Emerging energy conversion and storage devices such as lithium-ion batteries, ultracapacitors, fuel cells, etc. have shown great potential in solving the problems of traditional energy shortages and unstable energy sources of renewable energy sources, and have received extensive attention from academia and industry. .
All along, the realization of fast and efficient electron/ion transfer processes in electrode materials is a goal pursued by people and is also a core technical issue for improving the performance of related devices. Compared with conventional bulk materials, the small size, large specific surface, and high surface atomic ratio of zero-dimensional nanomaterials (quantum dots) mean that the material is in contact with the electrolyte and the shorter ion diffusion distance is ideal. Electrode material. However, the application of quantum dots to electrochemistry is mostly unsatisfactory, which is closely related to the poor electrochemical activity of common quantum dot materials, surface organic ligand coating, and high interfacial resistance between particles.
Researcher Zhao Zhigang of the Institute of Nanotechnology and Nanobionics of the Chinese Academy of Sciences Zhao Zhigang and Prof. Fengxia Feng from Suzhou University have conducted detailed and in-depth studies on this issue, and made breakthroughs in the preparation of tungsten oxide quantum dots and their electrochemical applications. . They used tungsten-based metal organic complexes as precursors, single fatty amines as reactants/solvents, obtained uniform size, average particle size of only 1.6 nm, and can be monodispersed in WO3-x nanocrystals of organic solvents, and observed strong The quantum size effect solves the problem that tungsten oxide quantum dots are difficult to obtain, or must rely on lattice templates (silica gel, molecular sieves) to prepare.
The researchers further demonstrated that the QDs exhibited excellent electrochemical performance after replacing the long-chain fatty amines coated with quantum dots with pyridine molecules through simple ligand exchange. The charge-discharge and electrochromic test results show that: (1) CV peak shape and fine structure can still be maintained at a high scan rate of 500 mV/s, which shows higher rate characteristics; (2) Both the color generation and fade time are in 1s. Within the range, the color change efficiency can reach 154 cm2/C, which is superior to non-zero-dimensional tungsten oxide and other inorganic electrochromic materials.
This work confirms that reducing the particle size of traditional electrode materials to zero-dimensional will greatly enhance the material and charge transport processes, and is expected to expand the application of quantum dot materials in the field of ultra-fast response electrochemical devices. The results were published in Advanced Materials (Volume 26, Issue 25, pages 4260–4267, July 2, 2014).
Solar Panel,Poly Solar Panel,Mono Solar Panel,Solar Panel For Power Stations
Fuzhou Mei Li Cheng Imp&Exp Co., Ltd , https://www.mlc-solar.com