Chai Peng, Jin Yuekang, Sun Guanghui, Ding Liangbing, Wu Longxia, Wang Haocheng, Fu Cong, Wu Zongfang, Huang Weixin
Hefei National Laboratory for Physical Sciences at the Microscale, Key Laboratory of Surface and Interface Chemistry and Energy Catalysis of Anhui Higher Education Institutes, and Department of Chemical Physics, University of Science and Technology of China, Hefei 230026, People's Republic of China.
Rev Sci Instrum. 2022 May 1;93(5):054105. doi: 10.1063/5.0081102.
The model catalyst approach is often used for fundamental investigations of complex heterogeneous catalysis, in which operando characterizations are critical. A flow reactor is usually adopted for gas-solid heterogeneous catalytic reactions. Herein, we report a home-designed near-ambient pressure (NAP) flow reactor coupled with polarization-modulation infrared reflection absorption spectroscopy (PM-IRAS) and an online quadrupole mass spectrometer for operando studies of heterogeneous catalytic reactions over model catalysts. A unique gas supply system is designed and manufactured to enable a stable gas inlet to the NAP flow reactor at pressures up to ∼100 mbar. An ultrahigh vacuum chamber equipped with the facilities for x-ray photoelectron spectroscopy, low-energy electron diffraction, thermal desorption spectroscopy, E-beam evaporation source, and ion sputtering gun is connected to the NAP flow reactor via a gate valve for preparations and routine characterizations of model catalysts. The functions of the system are demonstrated by in situ PM-IRAS characterization of CO adsorption on Pt(111) and operando characterizations of CO oxidation on Pt(111) under NAP conditions.
模型催化剂方法常用于复杂多相催化的基础研究，其中原位表征至关重要。气固多相催化反应通常采用流动反应器。在此，我们报道了一种自行设计的近常压（NAP）流动反应器，它与偏振调制红外反射吸收光谱（PM-IRAS）和在线四极杆质谱仪联用，用于对模型催化剂上的多相催化反应进行原位研究。设计并制造了独特的气体供应系统，以确保在高达约100毫巴的压力下，能稳定地向NAP流动反应器供气。一个配备有X射线光电子能谱、低能电子衍射、热脱附光谱、电子束蒸发源和离子溅射枪等设备的超高真空腔室，通过闸阀与NAP流动反应器相连，用于模型催化剂的制备和常规表征。通过在NAP条件下对Pt(111)上CO吸附的原位PM-IRAS表征以及对Pt(111)上CO氧化的原位研究，证明了该系统的功能。
