Hierarchical Zinc Stannate Nanoneedle-Based Sensitive Detection of Formaldehyde

Abstract

Perovskite-type ternary metal oxides have persisted as an area of research toward developing interesting nanostructures and their subsequent application. The paper presents a nanodimensional needle-like hierarchical structure of zinc stannate (ZnSnO3) material for the sensitive detection of formaldehyde. The nanomaterial was successfully synthesized through a simple and low-cost hydrothermal process. The morphology and structural properties were validated through various material characterization techniques. The nanoneedles were formed with a definite shape having an average thickness and a length of 20 and 450 nm, respectively, along with high crystallinity. Additionally, the evolution process of the grown nanostructure was discussed considering the involved chemical reactions. The gas-sensing behavior was investigated, where the maximum response was found toward formaldehyde with admirable sensitivity, fast kinetics, complete reversibility, and good selectivity and reproducibility. The limit of detection was found to be 717 ppb using the power law theory of semiconducting gas sensors. The sensing mechanism was explained using adsorption theory and the corresponding electron depletion layer modulation. The reported results indicate the potential influence of the prepared ZnSnO3 nanoneedles toward efficient integration in various electrochemical applications.