高耐甲醇性和稳定性的纳米复合阴极催化剂
We report the preparation, characterization, and electrocatalytic properties of a novel nanocomposite cathode catalyst (TiOPc-Pt/NSWCNH), which was assembled using Pt nanoclusters, TiOPc nanocrystal, and nitrogen-doped single wal ed carbon nanohorns (NSWCNHs) as building blocks. TiOPc-Pt/NSWCNH was characterized by inserting Pt nanoparticles in nano-networks formed by stacked NSWCNHs, and connecting some of the Pt nanoparticles with TiOPc nanocrystals. TiOPc-Pt/NSWCNH exhibits high electrocatalytic activity, excel ent selectivity, and good durability for the oxygen reduction reaction (ORR) in the presence of methanol. In an O2-saturated HClO4 aqueous solution containing methanol (0.5 mol·L-1), the onset potential over the TiOPc-Pt/NSWCNH catalyst shifted by more than+260 mV relative to that over a commercial Pt/C-JM catalyst. The mass activity and specific activity for the ORR over TiOPc-Pt/NSWCNH at 0.85 V (versus a reversible hydrogen electrode (RHE)) were 83.5 A·g-1 and 0.294 mA·cm-2, respectively. These results are much higher than those for Pt/C-JM. Cyclic voltammetry accelerated aging tests (0.6-1.0 V for 15000 cycles) in an O2-saturated HClO4 aqueous solution containing methanol revealed that TiOPc-Pt/NSWCNH had higher durability than TiOPc-Pt/C. The high methanol tolerance of TiOPc-Pt/NCNH may be mainly derived from electron transfer from TiOPc nanocrystals to Pt nanoparticles. The nano-network and the high graphitization degree of the NSWCNHs are responsible for the excel ent durability of TiOPc-Pt/NSWCNH.
O646.54(物理化学（理论化学）、化学物理学)
2012-11-08（万方平台首次上网日期，不代表论文的发表时间）
共6页
2263-2268
