Formic Acid Gas Sensors Based on Electrolytically Exfoliated Graphene-loaded Flame-Made Spinel Zn2SnO4 Composites

Abstract

In this work effective gas-sensing material were prepared by combining spinel zinc stannate (Zn2SnO4) nanoparticles synthesized by flame spray pyrolysis and graphene produced by the electrolytic exfoliation for volatile organic acids (VOAs) detection. The effect of graphene content in the range of 0.2�wt% on formic acid (HCOOH)-sensing performance of Zn2SnO4 nanoparticles was evaluated. Structural physical and chemical properties were investigated using X-ray diffraction Raman spectroscopy BET-surface analysis energy dispersive X-ray spectroscopy and electron microscopy. From the gas-sensing test towards 0.005-0.1 vol% HCOOH in dry air at 200-400?C the graphene-loaded Zn2SnO4 sensor with the optimal graphene content of 0.5 wt% displayed the highest response of ~4970 towards HCOOH at the optimal temperature of 300?C. Moreover it showed high HCOOH selectivity against several other VOAs volatile organic compounds and environmental gases. Therefore graphene-loaded spinel Zn2SnO4 sensors could be attractive choices for selective HCOOH detection and useful for food science and industrial applications. ? 2023 Chiang Mai University. All rights reserved.