通过引入乙烯作为C-C键分裂的前体来加速乙醇的完整电氧化
Teng Chen1,2, Shen Xu3, Taotao Zhao2
1Air Force Logistics Academy, Xuzhou, Jiangsu, 221000, China.
Angewandte Chemie (International ed. in English)
|August 7, 2023
概括
一种新型的催化剂,Pt/Al2O3@TiAl,通过乙烯通路实现了完全的乙醇氧化,克服了直接乙醇燃料电池 (DEFC) 的局限性. 这一突破提高了DEFC的性能和耐用性.
科学领域:
- 电化学 电化学 电化学
- 材料科学 材料科学 材料科学
- 催化剂是一种催化剂.
背景情况:
- 由于稳定的C-C键,直接乙醇燃料电池 (DEFC) 受到不完整的乙醇电氧化阻碍.
- 开发用于乙醇氧化反应 (EOR) 的高效催化剂对于推进DEFC技术至关重要.
研究的目的:
- 提出一种新的以乙烯为媒介的途径,在乙醇氧化中实现100%的C1选择性.
- 开发和描述一个带有级联活性位点的Pt/Al2O3@TiAl催化剂,以增强EOR.
主要方法:
- 使用现场电化学里埃变换红外光谱法 (FTIR) 和微分电化学质谱法 (DEMS).
- 进行了X射线吸收光谱和密度函数理论 (DFT) 研究.
- 催化剂的性能被评估为活性和耐用性.
主要成果:
- 确定了一种独特的以乙烯为媒介的EOR途径,具有100%的C1选择性.
- 该Pt/Al2O3@TiAl催化剂证明了有效的乙醇脱水和乙烯氧化.
- 在Pt纳米晶体中的Al兴奋剂降低了反应障碍,并消除了有毒物种,增强了EOR动力学.
结论:
- 该Pt/Al2O3@TiAl催化剂的特异活性是商业Pt/C的7.4倍.
- 催化剂显示出优越的长期耐用性,为实际的DEFC应用铺平了道路.
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