 |
Recently, Wu Zhongshuai, a researcher of the 2D Materials and Energy Devices Research Group of the Dalian Institute of Chemical Physics, Chinese Academy of Sciences, used a bottom-up pyrolysis method to prepare continuous, uniform, ultra-thin sulfur-doped graphene films, and applied them to them. High-capacity micro-supercapacitors, related research results published in the "American Chemical Society" (J. Am. Chem. Soc., DOI: 10.1021/jacs.7b00805). The work was focused on by Acta Physico-Chimica Sinica, a professor at Peking University, and Liu Zhongfan, an academician of the Chinese Academy of Sciences. He wrote on the bottom-up method of preparing sulfur-doped graphene films for miniaturization. The highlight of the article “Super Capacitors†(DOI: 10.3866/PKU.WHXB201703171) was followed by a Highlight report.
The rapid development of highly integrated, light-weight portable and functional structural integrated electronic devices urgently requires new energy storage devices that are compatible with them. Miniature supercapacitors have attracted much attention because of their advantages such as lightweight, small size, and high power density. Among them, the development of high-performance electrode materials is one of the important research directions for realizing high-performance miniature supercapacitors. The study found that one or more heteroatoms (nitrogen, boron, sulfur) doped graphene can significantly improve the performance of supercapacitors; however, with nanographene as the precursor, the uniform thickness from the bottom to the top is precisely prepared. The area of ​​sulfur-doped graphene films still faces great challenges.
The research team used the two-dimensional nano-confinement effect of nano-gold layer and gold catalysis to successfully prepare a continuous and uniform sulfur-doped graphene film from the bottom-up progressively pyrolysis method; this thin-film electrode was used. Micro-nano processing technology builds a miniature super capacitor. The capacitor has the advantages of high volumetric specific capacity (582F/cm3), good cycle stability, and high power density (1191 W/cm3). The mechanism study shows that the existence of nano-gold thin layer is conducive to the formation of stable S-Au bonds, CS bonds, thus achieving the complete structure of the nanographene main body, uniform doping of sulfur elements and uniform film thickness. This work provides a new idea for the controllable preparation of large-area, continuous graphene films from the bottom-up process; it also provides a new method for sulfur-doped graphene and confirms that sulfur doping can significantly improve the electrochemical performance of graphene films. performance.
The above work was funded by the National Natural Science Foundation of China, the National Key Research and Development Program, the Natural Science Foundation of Liaoning Province, and the National Youth 1000-member Program.
The most common applications that machine screws tend to be used for involve metal parts and panels needing to be fixed securely together. This is a daily requirement across all manner of industrial, manufacturing, construction, assembly, process, and production environments.
How do you use machine screws? Simply put, you use machine screws in much the same way as you would use any other type of screw or bolt.
Follow the below steps for guidance on using machine screws:
You use a machine screw by drilling or tapping it into a pre-drilled hole or nut, using either a manual or powered screwdriver
Power tools are frequently associated with the use of machine screws. This is because fasteners of this type are typically demanded in more heavy-duty or industrial-scale assembly and construction jobs
In the vast majority of scenarios, machine screws will be used with a nut and driven into a pre-drilled (tapped) hole. When using a nut with a machine screw, the nut will typically go behind the rearmost component or part being fastened
Machine screws are versatile and are often used to join two or more different parts or components. Sometimes, they are also chosen to hold down or sandwich gaskets and membranes, as well as being used on terminal strips and for making numerous other sorts of electrical connections
A handy alternative use for machine screws is to separate and secure parts or panels which need to be kept at a fixed distance from one another. This is achieved via a type of threaded coupling which allows two machine screws to be driven in from opposing directions. The separation distance you require between parts will dictate the length of the coupling inserted between the two fasteners
Machine Screw,Countersunk Machine Screw,Self Tapping Machine Screws,Stainless Steel Machine Screws
Taizhou Risco Stainless Steel Products Co.,Ltd , https://www.riscofastener.com