Li Panpan, Zhang Xuejing, Wang Jingnan, Xue Yanming, Yao Yongbin, Chai Shanshan, Zhou Bo, Wang Xi, Zheng Nanfeng, Yao Jiannian
Department of Physics, School of Science, Beijing Jiaotong University, Beijing 100044, P. R. China.
School of Chemical Engineering and Technology, Molecular Plus and Collaborative Innovation Center of Chemical Science and Engineering, Tianjin University, Tianjin 300072, P. R. China.
J Am Chem Soc. 2022 Apr 6;144(13):5930-5936. doi: 10.1021/jacs.1c13563. Epub 2022 Mar 22.
Boron nitride (BN) has been widely studied as an efficient catalyst for oxidative propane dehydrogenation (OPDH). Oxygen-containing boron species (e.g., BO·, B()O) are generally considered as the active centers in BN for OPDH. Here, we show an effective progressive substitution strategy toward the development of boron-oxygen-nitrogen nanotubes (BONNTs) enriched with O-O species as a highly active, selective, and stable catalyst for OPDH. At 525 °C, an olefin yield of 48.6% is achieved over BONNTs with a propane conversion of 64.4%, 2.8 times that of boron nitrogen nanotubes (BNNTs). Even after reaction for 150 h (475 °C), BONNTs exhibit good olefin yield. Both the B()O and O-O species that coexist in the BONNT catalyst are demonstrated as active centers, which differs from the B()O one in BNNTs. Based on catalytic results, propane and oxygen alternate treatment experiments, and theoretical calculations, the O-O center is more favorable for producing both propylene (C) and ethylene (C), which experiences a dehydration pathway and two possible reaction paths with a lower energy barrier to yield olefins, while B()O is mainly responsible for producing few C.
氮化硼（BN）作为氧化丙烷脱氢（OPDH）的高效催化剂已得到广泛研究。含氧化硼物种（如BO·、B()O）通常被认为是BN用于OPDH的活性中心。在此，我们展示了一种有效的逐步取代策略，用于开发富含O - O物种的硼 - 氧 - 氮纳米管（BONNTs），作为OPDH的高活性、选择性和稳定催化剂。在525℃下，BONNTs的烯烃产率达到48.6%，丙烷转化率为64.4%，是硼氮纳米管（BNNTs）的2.8倍。即使在475℃反应150小时后，BONNTs仍表现出良好的烯烃产率。BONNT催化剂中共存的B()O和O - O物种均被证明是活性中心，这与BNNTs中的B()O不同。基于催化结果、丙烷和氧气交替处理实验以及理论计算，O - O中心更有利于生成丙烯（C）和乙烯（C），其经历脱水途径和两条能量垒较低的可能反应路径以生成烯烃，而B()O主要负责生成少量的C。
