Facile Preparation of Nanoporous PtCu Alloys for Preferential Oxidation of CO in Hydrogen-Rich System
摘要:
Nanoporous (NP) PtCu alloys were straightforwardly fabricated by a simple dealloying method, characterized by bicontinuous interconnected nanosponge structure with the typical size around 10 nm. By controlling the time of selectively etching PtCu source alloy, NP-PtCu alloys with three different compositions were easily obtained, whose catalytic activities were evaluated towards the preferential oxidation of CO (PROX) as a function of the residual Cu content. The presence of H-2 has little influence on the CO oxidation activity over PtCu catalysts for PROX reaction. NP-PtCu catalysts with three bimetallic compositions exhibit distinct PROX catalytic performance along with different CO conversions and selectivity. The maximal values of CO2 selectivity on Pt60Cu40 and Pt78Cu22 catalysts could reach as high as 70-75% at the temperature as low as 70 degrees C. Compared with Pt43Cu57 and Pt78Cu22, Pt60Cu40 sample shows the superior catalytic activity for PROX reaction with the higher CO conversion and CO2 selectivity in a wide temperature range of 50-160 degrees C. Moreover, NP-PtCu catalyst has excellent catalytic stability with almost no activity loss and structure coarsening upon consecutive cycling tests.
作者:Si-Bo Wang、Wei Zhu、Jun Ke、Jun Gu、An-Xiang Yin、Ya-Wen Zhang、Chun-Hua Yan
DOI:10.1039/c3cc43208d
日期:——
Porous PtâM (M = Cu, Zn, Ni) nanoparticles (NPs) were obtained by reduction of [Pt(CH3NH2)4][PtCl4] and M(Ac)2 (or MCl2) with oleylamine under mild conditions. The porous PtâCu NPs exhibited superior catalytic activities over a Pt/Cu NP mixture and Cu NPs as references for CO oxidation processes.
Monodisperse and self-assembled Pt-Cu nanoparticles as an efficient electrocatalyst for the methanol oxidation reaction
作者:Xuewei Du、Shuiping Luo、Hongyu Du、Min Tang、Xiangdong Huang、Pei Kang Shen
DOI:10.1039/c5ta09261b
日期:——
Monodisperse PtCu nanoparticles have been synthesized and can be self-assembled via adding oleylamine (OAM), and they show higher activity, stability and better CO tolerance compared with Pt/C toward the methanol oxidation reaction.
A mesoporous PtCu catalyst modified with a Ru submonolayer is successfully synthesized by a facile electrochemical process of electrodeposition, dealloying and Ru underpotential deposition. The material has a large specific surface area comparable to nanoparticles (11 m2 g−1) and exhibits a promising catalyst activity for the methanol oxidation reaction.
agent, also as the stabilizing agent. The average diameter of NWs was about 3.1 nm and NWs showed typical face-centered-cubic (fcc) alloy crystal structure. The influence of Pt/Cu ions ratios in precursor solution on the bimetallic composition of NWs had been studied, and NWs displayed the feature of composition-tuning. The electro-catalytic activity of Pt-Cu alloy NWs for ethylene glycol oxidation reaction
and Pt73Ni27 nanowires showed mass current densities of 390 (at 0.69) and 503 mA mg−1 (at 0.70 V), respectively. These mass current densities are much higher than that of Pt nanowires (356 mA mg−1 at 0.73 V) and commercial Pt black (195 mA mg−1 at 0.73 V). During the entire 2000 s current–time test, the porous Pt75Cu25 and Pt73Ni27 nanowires also exhibited higher stability for the methanol oxidation reaction
通过一步湿法化学溶液法成功地合成了多孔的Pt 75 Cu 25和Pt 73 Ni 27纳米线,这是首次无需使用任何模板。多孔和一维特征的结合以及第二种廉价金属的添加提供了较高的催化剂利用率,出色的催化活性和更好的甲醇氧化反应耐久性。多孔的Pt 75 Cu 25和Pt 73 Ni 27纳米线的质量电流密度分别为390(在0.69时)和503 mA mg -1(在0.70 V时)。这些质量电流密度远高于Pt纳米线的质量电流密度(356 mA mg -1在0.73 V时)和市售Pt黑(在0.73 V时为195 mA mg -1)。在整个2000 s的电流时间测试中,多孔的Pt 75 Cu 25和Pt 73 Ni 27纳米线对甲醇氧化反应的稳定性也比Pt纳米线和市售Pt黑线高。