||Preparation and Growth of N-Doped Hollow Carbon Nanospheres and Their Application as Catalyst Support in Direct Borohydride Fuel Cell
||Chen, Y. Z; Dong, S.; Li, S.; Liu, Y.; Yan, W.
||Journal of Nanoscience & Nanotechnology
||N-doped hollow carbon nanospheres (HCNSs) were prepared by electric arc discharge method in
N2 atmosphere. X-ray Photoelectron Spectroscopy (XPS) analysis shows that their nitrogen content
reaches up to 4.9 atom%. Both the low thermal conductivity of N2 and the doping of nitrogen atom
make carbon unit bend to form hollow nanosphere structure. High-resolution transmission electron
microscopy (HRTEM) and X-ray diffusion (XRD) analysis prove the presence of detected defects
and a poor crystallinity on the HCNSs shell. Moreover, annealing treatment of HCNSs was carried
out at 1100 C/10 h and 1400 C/2 h to research their fracture extension. It is found that HCNSs
could grow into closed-tubes even with a shell at high annealing temperature. HCNSs were applied
in direct borohydride fuel cell (DBFC) to evaluate their catalytic performance. The electrochemical
results show that pure HCNSs doesn’t have any catalysis effect, but they can greatly promote
the catalytic performance of CoO, and the largest polarization current density of which achieves
1.845 A · cm−2 at −0.7 V (vs. Hg/HgO electrode).