Novel SnO2(ZnO:Sn)m superlattice nanoparticles for ultra-low ppb-level H2S detection. Issue 22 (24th May 2022)

• Record Type: Journal Article
• Authors: Huang, Jianan; Xu, Bojia; Ge, Binghui; Xu, Yi; Cao, Baobao
• Is Part Of: CrystEngComm. Volume 24:Issue 22(2022)
• Page Start: 4021
• Page End: 4029
• Publication Date: 2022-05-24
• Subjects: Crystals -- Periodicals; Crystal growth -- Periodicals; Crystallography -- Periodicals; Cristaux -- Périodiques; Cristaux -- Croissance -- Périodiques; Cristallographie -- Périodiques; 548
• DOI: 10.1039/d2ce00506a
• Languages: English
• ISSNs: 1466-8033

Abstract

Abstract : Novel SnO2 (ZnO:Sn) m superlattice nanoparticles were synthesized by a simple method of annealing ZnO nanoparticles precoated with a sol–gel Sn–Zn–O precursor, showing an ultra-low H2 S detection limit of 5 ppb with good selectivity. Abstract : Novel zero-dimensional SnO2 (ZnO:Sn) m superlattice nanoparticles were synthesized by a simple method of annealing ZnO nanoparticles precoated with a sol–gel Sn–Zn–O precursor. The annealing temperature and duration were systematically evaluated, and the optimum condition was confirmed as 900 °C for 45 min to obtain ideally fully developed layered structures. Cs-corrected scanning transmission electron microscopy (STEM) revealed that the SnO2 (ZnO:Sn) m was composed of alternate stacking of a Sn–O octahedral layer and Sn-doped ZnO slab, which resulted from the anisotropic diffusion of Sn atoms in the ZnO basal plane. A gas sensor based on the SnO2 (ZnO:Sn) m superlattice nanoparticles exhibited a superior selectivity towards the poisonous gas of hydrogen sulphide (H2 S) among six different types of gases (ethanol, H2, CO, NO2, NH3 and H2 S), and an extreme low H2 S detection limit of 5 ppb at the working temperature of 400 °C, which was about 3–5 orders lower than that of most ZnO-based H2 S gas sensors in the literature. The drastic enhancement of the sensing properties of the SnO2 (ZnO:Sn) m superlattice nanoparticles was believed to originate from its unique layered structure, which forms a microcirculation of electrons between the Sn–O atomic layers and Sn-doped ZnO slabs with different work functions, thus greatly accelerating the adsorption and desorption rate of gas molecules and increasing the sensor sensitivity. These new SnO2 (ZnO:Sn) m superlattice nanoparticles were demonstrated to be a competitive H2 S sensing material candidate for practical application. In addition, the facile superlattice nanoparticles fabrication method presented here could be extended to synthesize other ZnO-based superlattice material systems.