Wang Ran, Li Guobo, Zong Xupeng, Wang Jiaxing, Xu Yuanjie, Jin Chengwen, Wang Mingzhe, Ma Peijie, Zhang Rui, Zheng Kun, Hu Jiangliang, Liao Junjie, Wang Jiancheng, Tang Yu, Dai Yihu, Wang Shudong, Wang Sheng
Dalian National Laboratory for Clean Energy, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 457 Zhongshan Rd, Dalian 116023, China.
State Key Laboratory of Clean and Efficient Coal Utilization, Key Laboratory of Coal Science and Technology, Ministry of Education, Taiyuan University of Technology, Taiyuan 030024, China.
Environ Sci Technol. 2025 Jun 24;59(24):12121-12131. doi: 10.1021/acs.est.5c03422. Epub 2025 Jun 10.
Supported Pt catalysts often exhibit limited effectiveness in achieving complete methane oxidation, which restricts their commercial application. However, Pt catalysts are particularly attractive, especially in sulfur-containing environments, where commercial Pd catalysts are more susceptible to sulfur poisoning. Therefore, developing highly active Pt sites and gaining a deeper understanding of the intrinsic mechanisms governing methane combustion over Pt catalysts is essential. In this study, we present a highly active stannic oxide supported platinum catalyst (Pt/SnO) for stable low-temperature methane combustion, achieving a T as low as 390 °C at a high gas hourly space velocity (GHSV) of 60,000 mL·g·h. This performance surpasses that of most other Pt catalysts as well as Pd/SnO and benchmark Pd/AlO. The superior SO tolerance of Pt/SnO was demonstrated by the stability of methane conversion at 500 °C, with only a minor reduction observed during the long-term online test. Characterization results indicate that the Pt atoms on SnO are electron-deficient and predominantly adopt a crowded configuration. In situ studies and density functional theory (DFT) calculations reveal that the electron-deficient, crowded Pt atoms enhance the chemisorption of CH molecules by withdrawing the electrons from CH, resulting in activated CH with an elongated C-H bond. This work provides an in-depth understanding of the nature of Pt active sites for high-performance methane combustion, offering valuable insights for the rational design of Pt-based catalysts.
负载型铂催化剂在实现甲烷完全氧化方面通常表现出有限的效率，这限制了它们的商业应用。然而，铂催化剂特别具有吸引力，尤其是在含硫环境中，因为商用钯催化剂更容易受到硫中毒的影响。因此，开发高活性的铂位点并更深入地了解铂催化剂上甲烷燃烧的内在机制至关重要。在本研究中，我们展示了一种用于稳定低温甲烷燃烧的高活性氧化锡负载铂催化剂（Pt/SnO），在60,000 mL·g·h的高气时空速（GHSV）下实现了低至390°C的T90。这一性能超过了大多数其他铂催化剂以及Pd/SnO和基准Pd/Al2O3。Pt/SnO卓越的抗硫性通过在500°C下甲烷转化率的稳定性得到证明，在长期在线测试中仅观察到轻微下降。表征结果表明，SnO上的铂原子缺电子且主要采用拥挤构型。原位研究和密度泛函理论（DFT）计算表明，缺电子、拥挤的铂原子通过从CH4中提取电子增强了CH4分子的化学吸附，导致C-H键伸长的活化CH4。这项工作深入了解了用于高性能甲烷燃烧的铂活性位点的本质，为基于铂的催化剂的合理设计提供了有价值的见解。
