• ·  Microwave
  • ·  Atmospheric Pressure Microwave   ·  Pressure Microwave   ·  Parallel Microwave
  • ·  Ultrasonic ·Low Temperature Ultrasound
  • ·  Ultraviolet Light
  • ·  Microwave Heating  ·  Atmospheric Pressure Synthesis  ·  Atmospheric Pressure Catalysis  ·  Atmospheric Pressure Extraction
  • ·  Sample Preparation   ·  Microwave Digestion
  • ·  Soil Digestion   ·   High Pressure Synthesis
  • ·  Solid Phase Synthesis  
  • ·  Organic Synthesis  
  • ·  Ionic Liquid Synthesis
  • ·  Degradation Of Natural Organic Matter
  • ·  Natural Product Extraction / Purification


Synthesis of a stable lithium-ion battery with polyethylene and alkanone

Page view


This paper, by a researcher from the Center of Renewable Energy Nanomaterials of Xiundefinedan Jiaotong University, discusses the synthesis of polyvinylpyrrolidone stabilized lithium ion batteries, and is published in the English core Journal of Electrochemistry.

In recent years, the research work of microwave chemistry instruments for material synthesis has become a hot trend in scientific research. Especially in the synthesis research of energy storage materials, the results are remarkable, and it has received great attention from scholars!


In surface exposure engineering, non-stoichiometric defects and morphologies are the key parameters affecting the performance of SnO2. Developing a synthesis program that can control all these variables as a whole to improve physical and chemical properties is a huge challenge. In this paper, a simple microwave hydrothermal method for SnO_2 (SnO_2- δ) nanocrystals doped with Sn2 and controlled exposure to {101} faces with nonstoichiometric three dimensional hierarchical structure is reported.

Using polyvinylpyrrolidone (PVP) as capping agent, ultrathin and ultra-large SnO2- δ nanoparticles were stabilized by introducing high concentration of NaOH, to avoid their dissolution in high alkaline environment. Thus, the nanoflake morphology with preferential growth surface (121) and dominant reaction surface {101} was formed. The structural characteristics of SnO2- δ were analyzed by XRD,SEM,TEM,FTIR,XPS and Mssbauer spectra. It was found that SnO2- δ contains 17at% Sn2 doping.

Compared with stoichiometric SnO_2, these non-stoichiometric SnO_2- δ layered structures exhibit superior lithium storage performance compared with stoichiometric SnO_2. This is due to the fact that it is an open layered structure consisting of flexible ultra-thin nanochips and carbon coatings with large specific surface area (82m2/g), which avoids agglomeration and provides porous channels for electrolyte and lithium ion diffusion.







This paper demonstrates that it is very easy to prepare non-stoichiometric SnO 2 -δ nanosheets with exposed {101} surface by microwave hydrothermal method, in which SnCl_2.2H2O is a tin source, Sn2 is a dopant, and PVP is a blocking agent. A stable preparation of SnO2-δ nanosheets in an aqueous alkaline solution. More importantly, NaOH acts as a directing agent, together with PVP promotes the growth of (121) surface-selective crystals, thereby exposing the {101}-based surface of single crystal SnO2-δ nanosheets.

The Mssbauer spectrum showed a large amount of Sn2 (17 at%), and FTIR and XPS analysis showed that carbonization occurred in the hydrothermal reaction of PVP and its derivatives under microwave irradiation. When used as a negative electrode material for lithium ion batteries, non-stoichiometric SnO2-δ coated with carbonized PVP (yellow) or carbon coating (black) has enhanced lithium storage properties due to Sn2 self-doping, carbonization - The synergy of the PVP (or carbon) cap layer and the unique layered structure of ultra-thin, flexible nanosheets.

More importantly, the three-dimensional layered nanostructures with open pore structure, large specific surface area and orientation are not only beneficial to the diffusion of electrolytes and lithium ions, but also maintain the structural integrity of the electrodes. Based on our best knowledge, the synthetic strategy developed is the first strategy to allow {101} surface exposure of SnO2, which is simultaneously self-doped with Sn2, which is dependent on the field of gas sensing, catalysis, and optoelectronics. And the physicochemical properties of defects are promising.

Application of Xianghu instrument in this thesis

Microwave water-heat parallel synthesizer (XH-800S, Beijing Xianghu Technology Development Co., Ltd.) was used for material preparation, and parallel experiments were carried out using 800S multiple parallel functions to understand non-stoichiometry with {101} faces. Formation mechanism of SnO2-δ nanosheets.