Новый катализатор топливных ячеек достиг крупного прорыва - Оборудование для литий-ионных аккумуляторов
27 Сен 2022
The commercial application of proton exchange membrane fuel cells is limited by the sluggish oxygen reduction kinetics at 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 the oxygen-containing species by alloying the transition metal M (M=Fe, Co, Ni, Cu, etc.) with the noble metal Pt. Enhanced catalytic activity for oxygen reduction.
Recent studies have shown that interfacial catalysts can provide another effective way to enhance the catalytic activity of oxygen reduction relative to surface catalysts. However, how to design efficient interfacial catalysts with novel interfacial enhancement mechanisms remains a great challenge.(Lithium - Ion Battery Equipment)
Carbides of transition metals have gained 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 interfacial catalyst by combining PtM and transition metal carbides remains a great challenge.
To solve these problems, Guo Shaojun's team from the School of Engineering of Peking University designed and developed a new type of dumbbell-shaped PtFe-Fe2C nanoparticles. The dumbbell-shaped PtFe-Fe2C nanoparticles were obtained by carbonizing dumbbell-shaped PtFe-Fe3O4 nanoparticles.
Electrochemical tests show that the specific activity and mass activity of the catalyst for oxygen reduction in acidic media reach 3.53 mAcm2 and 1.50 Amg1, respectively, which are 11.8 and 7.1 times higher than those of commercial Pt/C, respectively, and have excellent electrochemical stability. After 5000 cycles, the activity of the catalyst has almost no decay.
Further computational studies by the research team found that this unique structure has a novel barrier-free interfacial electron transport mechanism, which is more conducive to the electrocatalytic reaction and improves the electrocatalytic activity.
This barrier-free interfacial electron transport mechanism can also be extended to other electrocatalytic systems, such as the electrocatalytic hydrogen evolution reaction and the electrocatalytic reduction of hydrogen peroxide. The specific activity of the catalyst for hydrogen evolution in acidic medium reaches 28.2 mAcm2, which is 2.9 times higher than that of commercial Pt/C, respectively.
The detection limit of the hydrogen peroxide electrochemical sensor based on this catalyst reaches 2 nM. This work has guiding significance for the theoretical study of electrocatalysis and the development of novel high-efficiency fuel cell electrocatalysts, and also provides new ideas for the structural design of next-generation high-performance and low-cost electrocatalysts.
Recent studies have shown that interfacial catalysts can provide another effective way to enhance the catalytic activity of oxygen reduction relative to surface catalysts. However, how to design efficient interfacial catalysts with novel interfacial enhancement mechanisms remains a great challenge.(Lithium - Ion Battery Equipment)
Carbides of transition metals have gained 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 interfacial catalyst by combining PtM and transition metal carbides remains a great challenge.
To solve these problems, Guo Shaojun's team from the School of Engineering of Peking University designed and developed a new type of dumbbell-shaped PtFe-Fe2C nanoparticles. The dumbbell-shaped PtFe-Fe2C nanoparticles were obtained by carbonizing dumbbell-shaped PtFe-Fe3O4 nanoparticles.
Electrochemical tests show that the specific activity and mass activity of the catalyst for oxygen reduction in acidic media reach 3.53 mAcm2 and 1.50 Amg1, respectively, which are 11.8 and 7.1 times higher than those of commercial Pt/C, respectively, and have excellent electrochemical stability. After 5000 cycles, the activity of the catalyst has almost no decay.
Further computational studies by the research team found that this unique structure has a novel barrier-free interfacial electron transport mechanism, which is more conducive to the electrocatalytic reaction and improves the electrocatalytic activity.
This barrier-free interfacial electron transport mechanism can also be extended to other electrocatalytic systems, such as the electrocatalytic hydrogen evolution reaction and the electrocatalytic reduction of hydrogen peroxide. The specific activity of the catalyst for hydrogen evolution in acidic medium reaches 28.2 mAcm2, which is 2.9 times higher than that of commercial Pt/C, respectively.
The detection limit of the hydrogen peroxide electrochemical sensor based on this catalyst reaches 2 nM. This work has guiding significance for the theoretical study of electrocatalysis and the development of novel high-efficiency fuel cell electrocatalysts, and also provides new ideas for the structural design of next-generation high-performance and low-cost electrocatalysts.