酸纳米管中的工程O-O物种增加了氧化脱的奥莱芬
Panpan Li1, Xuejing Zhang2, Jingnan Wang3
1Department of Physics, School of Science, Beijing Jiaotong University, Beijing 100044, P. R. China.
Journal of the American Chemical Society
|March 22, 2022
概括
具有O-O物种的-氧-纳米管 (BONNT) 显著提高了氧化脱 (OPDH) 的性能. 与传统的化纳米管 (BNNT) 相比,这些新型催化剂具有更高的活性,选择性和稳定性.
科学领域:
- 材料科学
- 催化剂
- 化学工程
背景情况:
- 化 (BN) 是已知的氧化脱 (OPDH) 的催化剂.
- 含有氧的物种,如BO·和B(OH) O3-,通常被认为是OPDH的BN催化剂中的活性位点.
研究的目的:
- 开发一种新型-氧-纳米管 (BONNTs) 催化剂,富含O-O物种.
- 研究BONNTs对OPDH的增强催化活性,选择性和稳定性.
主要方法:
- 使用渐进替代策略合成BONNT.
- 在525°C下对BONNT进行OPDH的催化试验.
- 长期稳定性测试在475°C进行150小时.
- 包括气和氧气交替处理在内的实验分析.
- 理论计算以阐明反应机制.
主要成果:
- 在525°C时,BONNT的转化率为64.4%,olefin的产量为48.6%,比BNNT高出2.8倍.
- 即使在475°C反应150小时后,BONNT也显示了持续高的烯酸产量.
- 与BNNT中的B(OH) O3-中心不同,B(OH) O3-和O-O物种都被确定为BONNT中的活性中心.
结论:
- 在BONNT中共存的B(OH) O3-和O-O物种作为OPDH的活性中心.
- 通过具有较低能量障碍的脱水途径,O-O物种更有效地产生 (C3=) 和乙烯 (C2=).
- BONNTs是OPDH的高度活跃,选择性和稳定的催化剂,比BNNTs提供了显著的改进.
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