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植物封闭的CeOx与协同的格子扭曲和氧气空隙驱动高效的尿素电合成
Ziming Zhao1,2, Yaru Wei1,2, Haoyu Duan1,2
1Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing, 400714, P. R. China.
Advanced science (Weinheim, Baden-Wurttemberg, Germany)
|November 4, 2025
概括
研究人员在一个多孔的碳框架内开发了网格扭曲的氧化纳米粒子,用于高效的电催化尿素合成. 这种新型催化剂加速了碳-联反应,为从废物中生产尿素提供了可持续的途径.
科学领域:
- 材料科学 材料科学 材料科学
- 电化学 电化学 电化学
- 催化剂是一种催化剂.
背景情况:
- 从二氧化碳和酸盐的电催化尿素合成面临着由于缓慢的多电子动力学和未定义的C-N合机制的挑战.
- 现有的催化剂在将废物转化为有价值的化学物质 (如尿素) 的效率和稳定性方面扎.
研究的目的:
- 设计和合成一种用于高效电催化尿素合成的新型催化剂.
- 阐明C-N合的机制,并确定影响反应动力学的关键因素.
- 提高催化剂的稳定性和活性,以实现可持续的尿素生产.
主要方法:
- 在一个多孔的碳框架 (d-CeOx/PC) 中制造网格扭曲的氧化 (CeOx) 纳米粒子,使用植物过度积累的限制策略.
- 催化剂结构的表征,包括纳米粒子大小,Ce-O键的长度和氧空隙度.
- 在现场减弱总反射里埃变换红外光谱 (ATR-FTIR) 检测反应中间体.
- 理论计算 (密度函数理论) 用于研究电子结构,反应路径和能量障碍.
主要成果:
- d-CeOx/PC催化剂呈现出超微小 (≈2 nm) 和均分散的CeOx纳米粒子,具有收缩的Ce-O键 (≈2.29 Å) 和丰富的氧空缺 (OV).
- 在现场ATR-FTIR和理论计算证实了涉及关键中间体 (*CO/*NO) 的C-N合路径,并确定了在速率决定步骤中显著降低的能量屏障 (0.18 eV).
- 设计的催化剂证明了反应剂吸附的增强,稳定了中间体,抑制了竞争中的化通路,并实现了优异的耐用性 (>100小时).
结论:
- 网格扭曲和CeOx纳米颗粒中的氧气空缺,被限制在一个多孔的碳框架内,为电催化尿素合成创造了一个积极的环境.
- 合约的Ce-O键在稳定Ce3+和促进多步电子转移方面发挥着至关重要的作用,从而降低了C-N合能障碍.
- 这项研究为尿素电合成提供了机理性的见解,并为设计有效和耐用的催化剂提供了有希望的策略,以从废物中生产可持续化学品.
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