State Key Laboratory of Chemical Resource Engineering, School of Science, Beijing University of Chemical Technology, Beijing 100029, P. R. China
基金项目：
The project was supported by the Beijing Municipal Science and Technology Program, China(Z171100000917019);the National Key Research and Development Program of China(2016YFB0101203);the National Natural Science Foundation of China(21376022);the National Natural Science Foundation of China(21476020);International S & T Cooperation Program of China(2013DFA51860);Fundamental Research Funds for the Central Universities, China(JC1504)
State Key Laboratory of Chemical Resource Engineering, School of Science, Beijing University of Chemical Technology, Beijing 100029, P. R. China
Abstract:
A series of nanocatalysts consisting of acid treated carbon nanotubes (CNTs) with different diameters (8-15, 20-30, 30-50, >50 nm) supporting platinum (Pt) nanoparticles (Pt/CNTs) were synthesized via a microwave-assisted ethylene glycol method. The as-synthesized catalysts were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), thermogravimetric analysis (TGA), and transmission electron microscopy (TEM). Their catalytic performances in the oxygen reduction reaction (ORR) were evaluated by cyclic voltammetry (CV) and linear sweep voltammetry (LSV). The experimental results showed that the diameter of the CNTs influences the particle size, loading, and dispersion of Pt NPs. Furthermore, the Pt/CNTs having different CNT diameters displayed different catalytic activities in the ORR. The catalyst Pt/CNT8, which was prepared by using CNTs with diameters ranging between 8-15 nm as the support, exhibited the highest Pt loading, catalytic activity, and stability in the ORR. The mass activity of Pt/CNT8 was determined to be 0.188 A·mg-1 at 0.9 V, which is folds higher than that of the commercially available JM Pt/C catalyst. After testing the stability for 5000 potential cycles, the negative shift (~7 mV) of the half-wave potential for Pt/CNT8 was found to be significantly lesser than that for the JM Pt/C catalyst (~32 mV), indicating superior catalytic stability.
