在非传统的2H-Pd纳米粒子上选择异相纳米结构的相向增长
Yiyao Ge1,2, Zhiqi Huang1,2, Chongyi Ling1
1Department of Chemistry, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong SAR, People's Republic of China.
Journal of the American Chemical Society
|October 22, 2020
概括
研究人员合成了具有独特异相结构的新金 (Pd@Au) 纳米棒. 这些Pd@Au纳米棒在电化学转化二氧化碳 (CO2) 变成一氧化碳 (CO) 方面表现出极高的效率.
科学领域:
- 材料科学和纳米技术
- 催化剂
- 电化学
背景情况:
- 贵金属异构纳米材料在各种应用中具有显著的潜力.
- 精确定义的贵金属异相纳米结构的控制合成仍然是一个重大挑战.
研究的目的:
- 开发一种合成非传统的六角密封 (2H型) (Pd) 纳米粒子的方法.
- 使用这些2H-Pd纳米颗粒作为其他贵金属的表层生长的种子,创建异相核心纳米结构.
- 在电化学二氧化碳还原反应 (CO2RR) 中研究这些新型纳米结构的催化性能.
主要方法:
- 无形Pd纳米颗粒的控制相位转化形成2H-Pd纳米颗粒.
- 在2H-Pd种子上的Au,Ag,Pt,PtNi和PtCo的面向,晶体相选择性表层生长.
- 由此产生的核心外纳米结构的表征 (例如,Pd@Au,Pd@Ag,Pd@Pt,Pd@PtNi,Pd@PtCo).
- 对Pd@Au纳米棒的电化学CO2RR性能评估.
主要成果:
- 通过受控相转换成功合成2H-Pd纳米粒子.
- 通过表轴生长实现了明确的面中心立方体 (fcc) - 2H-fcc异相Pd@Au核心纳米棒.
- 将这种合成策略扩展到其他异相核心纳米结构 (Pd@Ag,Pd@Pt,Pd@PtNi,Pd@PtCo).
- 在一个广泛的潜在窗口中,Pd@Au纳米棒在CO2RR中表现出超过90%的法拉达效率 (-0.9到-0.4V与RHE).
结论:
- 展示了一种用于制备贵金属异相纳米材料的新方法.
- 合成的fcc-2H-fcc Pd@Au纳米棒是CO2RR的高效电催化剂.
- 这项工作为设计先进的二氧化碳转化催化剂开辟了新的途径.
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