Quantitative Structure–Activity Relationship of Nanowire Adsorption to SO2 Revealed by In Situ TEM Technique

• Published in: Nano letters 2021-02, Vol.21 (4), p.1679-1687
• Main Authors: Wang, Xueqing, Yao, Fanglan, Xu, Pengcheng, Li, Ming, Yu, Haitao, Li, Xinxin
• Format: Article
• Language: English
• ISSN: 1530-6984; 1530-6992
• DOI: 10.1021/acs.nanolett.0c04481

A quantitative structure–activity relationship (QSAR) is revealed based on the real-time sulfurization processes of ZnO nanowires observed via gas-cell in situ transmission electron microscopy (in situ TEM). According to the in situ TEM observations, the ZnO nanowires with a diameter of 100 nm (ZnO-100 nm) gradually transform into a core–shell nanostructure under SO2 atmosphere, and the shell formation kinetics are quantitatively determined. However, only sparse nanoparticles can be observed on the surface of the ZnO-500 nm sample, which implies a weak solid–gas interaction between SO2 and ZnO-500 nm. The QSAR model is verified with heat of adsorption (−ΔH°) and aberration-corrected TEM characterization. With the guidance of the QSAR model, the following adsorbing/sensing applications of ZnO nanomaterials are explored: (i) breakthrough experiment demonstrates the application potential of the ZnO-100 nm sample for SO2 capture/storage; (ii) the ZnO-500 nm sample features good reversibility (RSD = 1.5%, n = 3) for SO2 sensing, and the detection limit reaches 70 ppb.