Fig. 1 TEM image of Pt/CNTs; (c-e) TEM image of Pt/GNTs; (f) TEM image of Pt/rGO
Figure 2 (a) i-t curves of Pt/GNTs and commercial Pt/C and (b) CV curves
Recently, the Institute of Plasma Physics, Institute of Plasma Physics, Chinese Academy of Sciences, Wang Qi's Research Group for Plasma Applications, has made progress in the oxidation of methanol. The relevant content was published in Applied Surface Science.
The direct methanol fuel cell (DMFC) works on the principle that during the redox reaction, the methanol of the anode loses electrons under the action of the catalyst, passes through the external circuit to the cathode, and simultaneously hydrogen ions (acid electrolyte) pass through the electrolyte The film is transferred from the anode to the cathode, and then the oxygen of the cathode is catalytically reduced to obtain electrons to form a current loop to provide electrical energy. Among them, the methanol oxidation reaction of the catalyst to the anode is very important. In recent years, related research has become more and more in-depth, mainly from the improvement of precious metal catalysts. The utilization rate, modification of carriers and preparation of alloy catalysts to improve the anti-intoxication ability and other aspects start. Platinum (Pt) as a superior performance precious metal catalyst has been of concern to researchers, in which the carriers loaded with platinum nanoparticles are often the ultimate catalytic performance It has a great influence. Graphene oxide is often used as a carrier for noble metals. However, using graphene oxide as a carrier directly, the electrochemical performance test can not achieve the desired effect.
The researchers self-assemble graphene oxide (GO) and carbon nanotubes (CNTs) to form a three-dimensional structure, then loaded with platinum, and can get platinum-based three-dimensional graphene-carbon nanometers with large specific surface area through hydrogen plasma discharge. Pipe catalysts (Pt/GNTs) have excellent catalytic performance for methanol oxidation. The technical route synthesizes the advantages of GO and CNTs to form a three-dimensional composite structure through self-assembly, which increases the specific surface area and is more conducive to the distribution of platinum nanoparticles. (Figure 1). Subsequently, the researchers prepared a series of different GO and CNTs mass ratios (GO: CNTs=0:1, 1:6, 1:4, 1:2, 1:1, 2:1). , 4:1, 6:1, and 1:0) catalysts, and found that GO: CNTs=1:2 had the best catalytic performance for methanol, and the current density was as high as 691.1 mA/mg. This value was higher than that of commercial platinum carbon catalysts. The increase was 87.7%, and was superior to most of the other reported catalysts. After 3600s of CA testing, the current density remained high (Figure 2). This result has a lot to do with the structural properties of the carrier. This study is of great significance for the preparation of a highly efficient methanol oxidation catalyst. Preparation of support also provides a new idea.
The research work was supported by the National Natural Science Foundation of China, the Anhui Outstanding Young Scientists Fund, the Talent Promotion Program of the Chinese Academy of Sciences Green Promotion Society, and the Hefei Research Institute Dean Fund.
