以碳黑（Vulcan XC 72）为载体,氯铱酸（H2IrCl6.6H2O）和氯铂酸（H2PtCl6.6H2O）为前驱体,聚乙烯基吡咯烷酮（PVP,polyvinylpyrrolidone）为保护剂,首次采用高压氢还原方法制备出PtIr/C合金催化剂,并对其进行不同温度的通H2热处理。运用XRD、TEM和XPS对PtIr/C合金催化剂进行表征。结果表明,Pt与Ir发生合金化,PtIr合金纳米粒子均匀分散在碳黑表面。经400和700℃热处理后,PtIr合金纳米粒子的平均粒径仅从4.46nm长大至4.56和5.58nm,且随着热处理温度的升高,其晶型不断完善。用CO-stripping伏安法,循环伏安法（CV）、计时电流法（CA）等电化学测试方法测试PtIr/C合金催化剂的电催化性能,发现400℃热处理的PtIr/C合金催化剂,在酸性溶液中对CO氧化的起始电位明显提前,对甲醇氧化具有最高的催化活性。
For the first time, Ptlr/C alloying catalysts were synthesized by high-pressure hydrogen reduction method using H2IrC16 · 6H20 and H2PtC16 · 6H20 as Ir and Pt precursors, polyvinylpyrrolidone as dispersing agent, in ethylene glycol solution, then further heat treated at different temperatures in H2 gas. The PtIr/C alloying catalysts were characterized by X-ray diffraction （XRD）, transmission electron microscopy （TEM） and X-ray photoelectron spectroscopy （XPS）. The results revealed that the PtIr nanoparticles were alloying catalysts, the metal particles were good dispersed on the caubon surface. After heat treated at 400 and 700°C, the mean particle sizes of PtIr nanoparticles just increased from 4.46 to 4.56 and 5.58nm, and with the increasing at heat treatment temperature, the crystal structure of PtIr alloying nanoparticles improved. CO-stripping voltammetry, cyclic voltammetry （CV） and chronoamperometry （CA） were used to characterize the catalytic performance of PtIr/C alloying catalysts toward CO and methanol electro-oxidation. PtIr/C catalysts had a lower oxidation starting potential towards CO oxidation in acid Solution and a better catalytic activity towards methanol oxidation.
参考文献
| [1] | Dillon R;Srinivasan S;Arico S et al.[J].Journal of Power Sources,2004,127(1-2):112-126. |
| [2] | Zhong C J;Luo J;Fang B et al.[J].Nanotechnology,2010,21:062001-062020. |
| [3] | Cheng X;Shi Z;Nancy G et al.[J].Journal of Power Sources,2007,165:739-756. |
| [4] | Xu Y Y;Dong Y N;Yang X K et al.[J].Catalysis Communications,2011,13:54-58. |
| [5] | Mallik K;Mandal M;Pradhan N et al.[J].Nano Letters,2001,6(01):319-322. |
| [6] | Bezerra C W B;Zhang L;Lee K et al.[J].Electrochimica Acta,2008,53:4937-4951. |
| [7] | Cheng X;Shi Z;Nancy G et al.[J].Journal of Power Sources,2007,165:739-756. |
| [8] | Nanba T;Wada K;Masukawa S .[J].Applied Catalysis A:General,2010,380:66-71. |
| [9] | Weststrateb C J;Bakkera J W;Gluhoi A C et al.[J].Catalysis Today,2010,154:46-52. |
| [10] | Reyes P.;Rojas H.;Fierro JLG. .Kinetic study of liquid-phase hydrogenation of citral over Ir/TiO2 catalysts[J].Applied Catalysis, A. General: An International Journal Devoted to Catalytic Science and Its Applications,2003(1/2):59-65. |
| [11] | Reyes P;Rojas H;Fierro J L G .[J].Journal of Molecular Catalysis A:Chemical,2002,179:293-299. |
| [12] | Sivakumar P;Tricoli V;Electrochem J .[J].Solid-State Letters,2006,9(03):A167-A170. |
| [13] | Liang YM;Zhang HM;Zhong HX;Zhu XB;Tian ZQ;Xu DY;Yi BL .Preparation and characterization of carbon-supported PtRuIr catalyst with excellent CO-tolerant performance for proton-exchange membrane fuel cells[J].Journal of Catalysis,2006(2):468-476. |
| [14] | Gao L;Sun G Q;Li H Q et al.[J].Electrochemistry Communications,2007,9:2541-2546. |
| [15] | Shen S Y;Zhao T S;Xu J B .[J].Electrochimica Acta,2010,55:9179-9184. |
| [16] | Tayal J;Rawat B;Basu S .[J].International Journal of Hydrogen Energy,2011,36:14884-14897. |
| [17] | Zeng J H;Yang J;Lee J Y et al.[J].Journal of Physical Chemistry B,2006,110:24606-24611. |
- 下载量()
- 访问量()
- 您的评分：
-
10%
-
20%
-
30%
-
40%
-
50%