谷物边界工程提升了协调不足的活跃站点,用于可扩展的CO2转化为乙烯
Yang Zhang1, Kun Qi1,2, Pengbo Lyu3
1Institut Européen des Membranes, IEM, UMR 5635, Université Montpellier, ENSCM, CNRS, Montpellier 34000, France.
ACS nano
|June 24, 2024
概括
研究人员开发了一种可扩展的方法,以提高铜催化剂的电化学二氧化碳减排性能,通过使用可再生能源将二氧化碳转化为有价值的多碳产品,实现高效率.
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
- 可持续化学 可持续化学
背景情况:
- 电化学二氧化碳减排 (CO2RR) 对可持续化学至关重要,其目的是利用可再生能源将二氧化碳转化为有价值的产品.
- 铜 (Cu) 催化剂对于生产多碳产品 (C2+) 是有前途的,但它们的效率受到确定内在活性和最大化活性位点的挑战的限制.
- 据假设,Cu催化剂中的粒度边界在CO2RR中发挥作用,通过调节关键中间体吸附,如*CO.
研究的目的:
- 开发一种可扩展的策略,以增加铜电极上协调不足的活性位点的密度.
- 为了研究谷物边界密度对降低二氧化碳的铜催化剂性能的影响.
- 量化谷物边界对CO2RR选择性和多碳产品形成的贡献.
主要方法:
- 采用直接的时空对比脉冲方法,创建具有高谷物边界活性位点 (GB-Cu) 密度的铜催化剂.
- 描述技术包括传输电子显微镜 (TEM),现场拉曼光谱和X射线光电子光谱 (XPS).
- 使用膜电极组件 (MEA) 电解器进行电化学测量,并配合太阳能电池进行太阳能到燃料 (STF) 效率评估.
主要成果:
- 对C2+产品的法拉戴效率与协调不足的地点的密度之间建立了线性相关性,证实了谷物边界的作用.
- GB-Cu 电极在 303.6 mA cm-2.2 时实现了 73.2% 的峰值 C2+ 法拉代效率和 20.2% 的全电池能效率.
- 在25厘米2的MEA电解器中,GB-Cu催化剂表现出极好的稳定性,在70小时内保持超过62%的选择性,电流保留率为88.4%.
- 通过将催化剂和电解剂与三联太阳能电池合,实现了8.33%的太阳能转化效率.
结论:
- 该研究成功设计和实施了一种缺乏协调的基于Cu的催化剂,最大限度地增加了谷物边界的暴露,显著提高了CO2RR的性能.
- 这项工作提供了一种方法来量化谷物边界对CO2RR的影响,并为开发用于太阳能驱动燃料生产的高效电催化装置提供了一条途径.
- 证明的高选择性,稳定性和太阳能燃料效率突出显示了这种方法在可持续化学中的实际应用潜力.
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