不对称的三原子位点限制在第三氧化物中,使选择性CO2光热降解为乙酸
Juncheng Zhu1, Weiwei Shao1, Xiaodong Li1
1Hefei National Laboratory for Physical Sciences at the Microscale, National Synchrotron Radiation Laboratory, University of Science and Technology of China, Hefei 230026, China.
Journal of the American Chemical Society
|October 22, 2021
概括
这项研究引入了一种新型的光催化系统,利用光诱导的热量来增强二氧化碳 (CO2) 减少到有价值的C2燃料中. 开发的非对称金属三原子位点和O空位显著提高了二氧化碳转化效率和酸盐生产的选择性.
科学领域:
- 材料科学
- 催化剂
- 摄影化学
背景情况:
- 传统的光催化通常忽略了光引起的热量,这对于将二氧化碳 (CO2) 减少为二氧化碳燃料等具有挑战性的反应来说是一个关键因素.
- 有效地将二氧化碳转化为有价值的燃料需要克服热力学和动力学障碍.
研究的目的:
- 设计一个先进的光催化系统,利用光诱导的热量来增强二氧化碳减排到二氧化碳燃料.
- 研究非对称金属三原子位点和氧空缺在促进C-C合和化步骤中的作用.
主要方法:
- 具有不对称的 Zn-O-Ge 三原子位点的 O-空位丰富的 Zn2GeO4 纳米带的制造.
- 使用准现场拉曼光谱识别反应部位.
- 使用密度函数理论 (DFT) 计算来阐明反应机制.
- 在现场进行福里埃变换红外光谱和D2O动态同位素效应实验以研究反应动力学.
主要成果:
- 不对称的Zn-O-Ge位点通过在C1中间体中产生明显的电荷分布来促进C-C合.
- 氧气空缺将决定化速度的能量障碍从1.46 eV降至0.67 eV.
- 光引起的热能加快了C-C合和OCCO*化,从而提高了酸盐的产生.
结论:
- 设计的光催化剂有效地利用光诱导的热量来有效地将二氧化碳降解为酸盐.
- 达到了高的乙酸输出 (12. 7μmol g-1 h-1) 和选择性 (66. 9%),二氧化碳转化为乙酸的比率为 29. 95%.
- 具有高达220小时的极佳催化稳定性.
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