1. Programmed temperature reduction method
Temperature programmed method is put forward in the eighty s is still the most widely used in a laboratory for the means of the MoC, the reaction experiment, molybdenum oxide is used as the source of molybdenum, hydrocarbon gas and hydrogen were used as the basis of carbon dioxide gas and reduction of materials, and temperature rising slowly to ensure in balance in the process of catalytic reaction speed, the composition and content of the monitoring tail gas by chromatography, Accordingly, the reaction process was evaluated and the reaction with carbonized raw materials was stopped in time to obtain MoC with larger surface area. The carbon sources in these catalytic reactions come from the pyrolysis products and hydrogen reactions of hydrocarbon gases at high temperatures.
2. Microwave pyrolysis
Microwave heating is rapid, and the system temperature can reach the set value in a short time, so as to reduce the preparation time of MoC to another level, which can effectively suppress the phenomenon of hot particles, so that MoC can be obtained from microwave solution, and the particles are uniform and small in size.
3. Chemical vapor deposition
Chemical vapor deposition is a treatment technique in which chemical reactions occur in the gas phase to deposit a solid onto the surface of a heated solid substrate. This is a process technology that can efficiently produce thin films under heavy load. Some researchers have used two-step precipitation and carbon dioxide formation methods to obtain MoC thin layers.
4. Sol-gel method
The gel was heated and evaporated at 60 ° C to 80 ° C, and then heated in hydrogen gas at 850 ° C for 14h to obtain hexagonal MoC. In addition, nickel and nickel carbide can be obtained by adding an appropriate amount of nickel acetate, which can be used to modify MoC.
5, biomass carbonization method
In recent years, the extraction of carbides from biomass has become very popular. There are many types of biomass, including renewable resources, which can therefore be used to produce large amounts of carbon. Because the carbon dioxide reaction occurs between the solid phase and the solid phase, it is easy to control.