Wei Haoshan, Xie Kui, Zhang Jun, Zhang Yong, Wang Yan, Qin Yongqiang, Cui Jiewu, Yan Jian, Wu Yucheng
Department of Energy Materials, School of Materials Science and Engineering, Hefei University of Technology, No.193 Tunxi Road, Hefei, Anhui 230009, China.
1] Department of Energy Materials, School of Materials Science and Engineering, Hefei University of Technology, No.193 Tunxi Road, Hefei, Anhui 230009, China [2] Key Laboratory of Advanced Functional Materials and Devices, Hefei University of Technology, No.193 Tunxi Road, Hefei, Anhui 230009, China.
Sci Rep. 2014 Jun 3;4:5156. doi: 10.1038/srep05156.
In this paper, we report the in situ growth of Ni(x)Cu(1-x) (x = 0, 0.25, 0.50, 0.75 and 1.0) alloy catalysts to anchor and decorate a redox-reversible Nb1.33Ti0.67O4 ceramic substrate with the aim of tailoring the electrocatalytic activity of the composite materials through direct exsolution of metal particles from the crystal lattice of a ceramic oxide in a reducing atmosphere at high temperatures. Combined analysis using XRD, SEM, EDS, TGA, TEM and XPS confirmed the completely reversible exsolution/dissolution of the Ni(x)Cu(1-x) alloy particles during the redox cycling treatments. TEM results revealed that the alloy particles were exsolved to anchor onto the surface of highly electronically conducting Nb1.33Ti0.67O4 in the form of heterojunctions. The electrical properties of the nanosized Ni(x)Cu(1-x)/Nb1.33Ti0.67O4 were systematically investigated and correlated to the electrochemical performance of the composite electrodes. A strong dependence of the improved electrode activity on the alloy compositions was observed in reducing atmospheres at high temperatures. Direct electrolysis of CO2 at the Ni(x)Cu(1-x)/Nb1.33Ti0.67O4 composite cathodes was investigated in solid-oxide electrolysers. The CO2 splitting rates were observed to be positively correlated with the Ni composition; however, the Ni0.75Cu0.25 combined the advantages of metallic nickel and copper and therefore maximised the current efficiencies.
在本文中，我们报道了Ni(x)Cu(1-x)（x = 0、0.25、0.50、0.75和1.0）合金催化剂的原位生长，以锚定和修饰氧化还原可逆的Nb1.33Ti0.67O4陶瓷基底，目的是通过在高温还原气氛中从陶瓷氧化物晶格直接析出金属颗粒来调整复合材料的电催化活性。使用XRD、SEM、EDS、TGA、TEM和XPS进行的联合分析证实了在氧化还原循环处理过程中Ni(x)Cu(1-x)合金颗粒的完全可逆析出/溶解。TEM结果表明，合金颗粒以异质结的形式析出并锚定在高电子导电性的Nb1.33Ti0.67O4表面。系统研究了纳米尺寸的Ni(x)Cu(1-x)/Nb1.33Ti0.67O4的电学性质，并将其与复合电极的电化学性能相关联。在高温还原气氛中观察到改进的电极活性对合金组成有强烈依赖性。在固体氧化物电解槽中研究了Ni(x)Cu(1-x)/Nb1.33Ti0.67O4复合阴极上CO2的直接电解。观察到CO2分解速率与Ni组成呈正相关；然而，Ni0.75Cu0.25结合了金属镍和铜的优点，因此使电流效率最大化。
