Yin Xi-Tao, Liu Ying, Tan Xiao-Ming, Gao Xiao-Chun, Li Jing, Ma Xiaoguang
School of Physics and Optoelectronic Engineering, Ludong University, Yantai, Shandong Province 264000, China.
The Key Laboratory of Chemical Metallurgy Engineering of Liaoning Province, University of Science and Technology Liaoning, Anshan, Liaoning Province 114051, China.
ACS Omega. 2022 Jun 9;7(24):21262-21266. doi: 10.1021/acsomega.2c02405. eCollection 2022 Jun 21.
The chemisorption phenomenon is widely used in the explanation of catalysis, gas-solid reactions, and gas sensing mechanisms. Generally, some properties of adsorbents, such as adsorption sites and dispersion, can be predicted by traditional methods through the variation of the chemisorption capacity with the temperature, pressure, and gas-solid interaction potential. However, these methods could not capture the information of the interaction between adsorbents, the adsorption rate, and the competitive adsorption relationship between adsorbents. In this paper, metal oxide semiconductors (MOSs) are employed to study the adsorption behavior. The gas sensing responses (GSRs) of MOSs caused by the gas adsorption process are measured as a new method to capture some adsorption behaviors, which are impossible for the traditional methods to obtain. The following adsorption behaviors characterized by this new method are presented for the first time: (1) distinguishing the adsorption type using an example of two reducing gases: the adsorption type of the two gases is single-molecular layer adsorption in this work; (2) detecting the interaction between different gases: this will be a promising method to provide original characterization data in the fields of gas-solid reaction mechanisms and heterogeneous catalysis; and (3) measuring the adsorption rate based on the GSR.
化学吸附现象广泛应用于催化、气固反应和气敏机理的解释。一般来说，吸附剂的一些性质，如吸附位点和分散性，可以通过传统方法，根据化学吸附容量随温度、压力和气固相互作用势的变化来预测。然而，这些方法无法获取吸附剂之间相互作用、吸附速率以及吸附剂之间竞争吸附关系的信息。本文采用金属氧化物半导体（MOS）来研究吸附行为。通过测量气体吸附过程引起的MOS的气敏响应（GSR），作为一种获取某些吸附行为的新方法，而这些行为是传统方法无法获得的。本文首次展示了用这种新方法表征的以下吸附行为：（1）以两种还原性气体为例区分吸附类型：在本工作中这两种气体的吸附类型均为单分子层吸附；（2）检测不同气体之间的相互作用：这将是一种在气固反应机理和多相催化领域提供原始表征数据的有前景的方法；（3）基于GSR测量吸附速率。
