New breakthrough in fuel power cell of Peking University -Lithium - Ion Battery Equipment
The commercial application of proton exchange membrane fuel cells is limited by the slow oxygen reduction kinetics of the cathode. At present, the most effective strategy to improve the catalytic activity of oxygen reduction is to optimize the bonding energy between the catalyst and oxygen containing species through the regulation of transition metal M (M=Fe, Co, Ni, Cu, etc.) and precious metal Pt alloying, so as to enhance the catalytic activity of oxygen reduction.(Lithium - Ion Battery Equipment)
Recent studies have shown that, compared with surface catalysts, interfacial catalysts can provide another effective way to enhance the catalytic activity of oxygen reduction. However, it is still a great challenge to design highly efficient interfacial catalysts with new interfacial enhancement mechanisms. Carbides of transition metals have received considerable attention in recent years due to their high electrical and thermal conductivity, excellent mechanical strength, hardness, chemical stability and corrosion resistance. Creating a new interface catalyst by combining PtM with transition metal carbides remains a huge challenge.
In order to solve these problems, Guo Shaojun's team of Peking University Institute of Technology designed and developed a new dumbbell like PtFe-Fe2C nanoparticles. This dumbbell like PtFe-Fe2C nanoparticles were obtained by carbonizing dumbbell like PtFe-Fe3O4 nanoparticles (Fig. 1a). The electrochemical test showed that the specific activity and mass activity of the catalyst for oxygen reduction in acid medium reached 3.53mAcm2 and 1.50Amg1 respectively, which were 11.8 and 7.1 times higher than commercial Pt/C respectively, and had extremely excellent electrochemical stability. The activity of the catalyst almost did not decline after 5000 cycles.
The research team further calculated and found that this unique structure has a novel barrier free interface electron transport mechanism, which is more conducive to the electrocatalytic reaction and thus improves the electrocatalytic activity (Fig. 1b). This barrier free interface electron transport mechanism can also be extended to other electro catalytic systems, such as electro catalytic hydrogen evolution reaction and hydrogen peroxide electro catalytic reduction. The specific activity of the catalyst for hydrogen evolution in acidic medium reached 28.2 mAcm2, 2.9 times higher than commercial Pt/C respectively.
The detection limit of hydrogen peroxide electrochemical sensor based on the catalyst reaches 2nM. This work has guiding significance for the theoretical research of electrocatalysis and the development of new high efficiency fuel cell electrocatalysts, and also provides a new idea for the structural design of the next generation high-performance low-cost electrocatalysts.
The work was completed by Guo Shaojun's team of Peking University Institute of Technology. Guo Shaojun is the corresponding author of the paper, and postdoctoral Lai Jianping and Dr. Huang Bolong of Hong Kong Polytechnic University are the co first authors. The project is supported by the National Natural Science Foundation of China and the key R&D plan of the Ministry of Science and Technology.
Recent studies have shown that, compared with surface catalysts, interfacial catalysts can provide another effective way to enhance the catalytic activity of oxygen reduction. However, it is still a great challenge to design highly efficient interfacial catalysts with new interfacial enhancement mechanisms. Carbides of transition metals have received considerable attention in recent years due to their high electrical and thermal conductivity, excellent mechanical strength, hardness, chemical stability and corrosion resistance. Creating a new interface catalyst by combining PtM with transition metal carbides remains a huge challenge.
In order to solve these problems, Guo Shaojun's team of Peking University Institute of Technology designed and developed a new dumbbell like PtFe-Fe2C nanoparticles. This dumbbell like PtFe-Fe2C nanoparticles were obtained by carbonizing dumbbell like PtFe-Fe3O4 nanoparticles (Fig. 1a). The electrochemical test showed that the specific activity and mass activity of the catalyst for oxygen reduction in acid medium reached 3.53mAcm2 and 1.50Amg1 respectively, which were 11.8 and 7.1 times higher than commercial Pt/C respectively, and had extremely excellent electrochemical stability. The activity of the catalyst almost did not decline after 5000 cycles.
The research team further calculated and found that this unique structure has a novel barrier free interface electron transport mechanism, which is more conducive to the electrocatalytic reaction and thus improves the electrocatalytic activity (Fig. 1b). This barrier free interface electron transport mechanism can also be extended to other electro catalytic systems, such as electro catalytic hydrogen evolution reaction and hydrogen peroxide electro catalytic reduction. The specific activity of the catalyst for hydrogen evolution in acidic medium reached 28.2 mAcm2, 2.9 times higher than commercial Pt/C respectively.
The detection limit of hydrogen peroxide electrochemical sensor based on the catalyst reaches 2nM. This work has guiding significance for the theoretical research of electrocatalysis and the development of new high efficiency fuel cell electrocatalysts, and also provides a new idea for the structural design of the next generation high-performance low-cost electrocatalysts.
The work was completed by Guo Shaojun's team of Peking University Institute of Technology. Guo Shaojun is the corresponding author of the paper, and postdoctoral Lai Jianping and Dr. Huang Bolong of Hong Kong Polytechnic University are the co first authors. The project is supported by the National Natural Science Foundation of China and the key R&D plan of the Ministry of Science and Technology.
