Ultra-sensitive H2S sensor based on sunflower-like In-doped ZnO with enriched oxygen vacancies

Yong-Hui Zhang; Ying-Ying Li; Xuan-Yu Yang; Fei-Long Gong; Jun-Li Chen; Ke-Feng Xie; Hao-Li Zhang; Shao-Ming Fang

doi:10.1039/d2cp02539f

Ultra-sensitive H₂S sensor based on sunflower-like In-doped ZnO with enriched oxygen vacancies

Phys Chem Chem Phys. 2022 Nov 30;24(46):28530-28539. doi: 10.1039/d2cp02539f.

Authors

Yong-Hui Zhang¹, Ying-Ying Li¹, Xuan-Yu Yang¹, Fei-Long Gong¹, Jun-Li Chen¹, Ke-Feng Xie², Hao-Li Zhang³, Shao-Ming Fang¹

Affiliations

¹ College of Materials and Chemical Engineering, Collaborative Innovation Center of Environmental Pollution Control and Ecological Restoration, Zhengzhou University of Light Industry, Zhengzhou 450002, P. R. China. yonghui.zhang@zzuli.edu.cn.
² School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou, Gansu 730070, P. R. China.
³ State Key Laboratory of Applied Organic Chemistry (SKLAOC); Key Laboratory of Special Function Materials and Structure Design (MOE); College of Chemistry and Chemical Engineering, Lanzhou University, Lanzhou, 730000, P. R. China.

PMID: 36411969
DOI: 10.1039/d2cp02539f

Abstract

Metal oxide sensors face the challenge of high response and fast recovery at low operating temperatures for the detection of toxic and flammable hydrogen sulfide (H₂S) gases. Herein, novel In-doped ZnO with a sunflower-like structure and tunable surface properties was rationally synthesized. The substitutional In atom in the ZnO crystal can dramatically enhance the concentration of oxygen vacancies (O_v), the In-ZnO sites are responsible for fast recovery, and the formation of sub-stable sulfide intermediates gives rise to the high response towards H₂S. As a result, the response of the optimized 4In-ZnO sensor is 3538.36 to 50 ppm H₂S at a low operating temperature of 110 °C, which is 106 times higher than that of pristine ZnO. Moreover, the response time and recovery time to 50 ppm H₂S are 100 s and 27 s, respectively, with high selectivity and stability. First-principles calculations revealed that 4In-ZnO with rich O_v exhibited higher adsorption energy for the H₂S molecule than pristine ZnO, resulting in effortless H₂S detection. Our work lays the foundation for the rational design of highly sensitive gas sensors through precise doping of atoms in oxygen-rich vacancies in semiconductor materials.