Lanzhou Chemicals won the controllable preparation of quantum-scale nickel hydroxide electrode materials.
 |
Transition metal hydroxides are widely used in energy, environmental protection, sensors and other fields. How to improve the electrochemical activity and stability of transition metal hydroxide has been a core issue in this field. Recently, the research group of the Clean Energy Chemistry and Materials Laboratory of the Lanzhou Institute of Chemical Physics, Chinese Academy of Sciences, has made progress in the preparation, characterization and electrochemical reaction mechanism processes of nickel hydroxide of very small size. The relevant research results are based on Ultra. -small, size-controlled Ni(OH)2 nanoparticles: elucidating the relationship between particle size and electrochemical performance for advanced energy storage devices was published online in June 2015 in the NPG Asia Materials magazine under the Nature Publishing Group.
For electrochemical energy storage materials, it is generally believed that the reduction of the particle size of the electrode material can shorten the ion or proton transmission path, thereby contributing to the improvement of its electrochemical activity and utilization. So, if the electrode material particle size is infinitely reduced, the electrochemical performance will be infinitely increased? It is well-known that when the electrode material is in the nanoscale (especially less than 10 nm), a nanoscale effect, such as a quantum size effect, will result, and the quantum size effect will cause the intrinsic physical and chemical properties of the material to change.
Will these changes affect the macro-electrochemical properties of electrochemical energy storage materials? However, it is still difficult at present to synthesize electrochemical energy storage materials with a size smaller than 10 nm and controllable size through an existing method, which hinders the relationship between the energy storage mechanism and particle size of the electrochemical energy storage materials. In-depth study. Based on his team's research on the controllable synthesis and energy storage mechanism of electrochemical energy storage materials for many years, Zang Xingbin's research team cleverly applied the complexation precipitation reaction method to realize the first time controllable synthesis of nickel hydroxide electrode materials below 10 nm. The prepared nickel hydroxide nanoparticles are small and uniform in size. This method is simple, low-cost and large-scale preparation. The relevant research results have been applied for national invention patents.
On this basis, the researchers further studied the electrochemical energy storage properties of nickel hydroxide by electrochemical analysis and testing techniques. It was found that the electrochemical energy storage performance of nickel hydroxide does not gradually increase with the decrease in particle size. There is a critical dimension, that is, when the particle size of the material is smaller than a certain particle size (critical size), the electrochemical performance will not continue to rise, but will decrease. This indicates that the energy storage properties of electrode materials may be affected by changes in the intrinsic physical and chemical properties.
The researchers further used UV spectroscopy and theoretical simulations to confirm that when the particle size of the energy storage material is smaller than the critical size, quantum size effects will occur, and the energy levels will migrate to higher energy states, resulting in a multiple decrease in the electrical conductivity. From the perspective of overall electrochemical oxidation reduction, a complete electrochemical redox reaction mainly includes three processes of ion transport, charge transfer and electron transport. Any process that is affected will affect the energy storage properties of the electrode material. This shows that when the particle size of the material is reduced below the critical size, the quantum size effect may be the cause of the decline in its electrochemical performance. In addition, the researchers also found that when the size of the material is reduced below the critical size, the proton/ion exchange rate will be anomalous.
Based on this, researchers proposed new insights into the energy storage mechanism of electrochemical energy storage materials in different sizes. The results of these studies will change the understanding that the smaller the size of the nano-electrode material is, the better its energy storage performance will be, and it will help guide the development of high-performance electrochemical energy storage materials. NPG Asia Materials made a comment on this study entitled Electrochemical energy storage: Smaller is not always better.
The above work has been funded and supported by the Lanzhou Institute of Chemical Subsidiary “One-Three-Five†key breeding project, the National Natural Science Foundation of China, and the State Key Laboratory of Solid Lubrication.
Phlizon COB series Grow Light, best full Spectrum designed to perfectly match large areas of indoor plants, hydroponics horticulture agriculture, and greenhouse, especially for indoor Plant.
3000K 5000K Cree COB and Epistar dual-chip,most efficient spectrum,high PPFD.Instead of having dozens of small diodes, COB style LED Grow Lights typically only have a handful of huge COBs, each with strong lenses to direct the light down into the plant.The big aluminum heat sink to protect the grow lights from high temperature,good cooling,long lifespan.Photosynthesis and promote healthy growth budding and flowering.
These are rapidly gaining in popularity and are known for having deep penetration into the plant canopy. 1000w/1500w/2000w /2500w /3000w COB light, they will give you more options when your plants need different strength of illumination.
PH-B-L3
Shenzhen Phlizon Technology Co.,Ltd. , https://www.szledaquariumlighting.com