ZnO-Loaded Graphene for NO2 Gas Sensing

Abstract

This paper investigates the effect of decorating graphene with zinc oxide (ZnO) nanoparticles (NPs) for the detection of NO2. In this regard, two graphene sensors with different ZnO loadings of 5 wt.% and 20 wt.% were prepared, and their responses towards NO2 at room temperature and different conditions were compared. The experimental results demonstrate that the graphene loaded with 5 wt.% ZnO NPs (G95/5) shows better performance at detecting low concentrations of the target gas than the one loaded with 20 wt.% ZnO NPs (G80/20). Moreover, measurements under dry and humid conditions of the G95/5 sensor revealed that the material is very sensitive to ambient moisture, showing an almost eight-fold increase in NO2 sensitivity when the background changes from dry to 70% relative humidity. Regarding sensor selectivity, it presents a significant selectivity towards NO2 compared to other gas compounds.

Development of an efficient electrochemical sensing platform based on ter-poly(luminol-o-anisidine-o-toluidine)/ZnO/GNPs nanocomposites for the detection of antimony (Sb3+) ions

“…4D–F) presented dispersed bright spots on the surface of the composite, forming small aggregated globules, demonstrating the presence of zinc oxide nanoparticles (ZnO NPs). 62,64 Furthermore, the images at higher magnification (Fig. 4F) exhibited relatively smooth black graphene sheets stacked together on the surface associated with the deposition and coating of graphene nanoplatelets (GNPs).…”

“…4F) exhibited relatively smooth black graphene sheets stacked together on the surface associated with the deposition and coating of graphene nanoplatelets (GNPs). 60–64 The nanocomposite images depict the advantage of network/layer structures with rough and well-defined topography, providing efficient electron transfer and high conductivity of graphene to produce suitable sensor structures for electrochemical Sb 3+ ion detection. 75…”

“…The combination of ZnO NPs and GNPs in sensor development has been described in numerous recent studies. 60–64 For instance, a new nanocomposite comprising ZnO nanoparticles and reduced graphene oxide (ZnONPs/N-rGO) was synthesized using a one-step hydrothermal process and subsequently modified as an electrochemical sensor for l -cysteine. 60 Additionally, a Zn-oxide-incorporated graphene-modified carbon paste electrode (ZnO-Gr/CPE) was fabricated to study the electrochemical properties of cetirizine.…”

“…63 Gas sensors were also investigated, and the effect of decorating graphene with ZnO nanoparticles on the detection of NO 2 has been reported. 64…”

ZnO Decorated Graphene-Based NFC Tag for Personal NO2 Exposure Monitoring during a Workday

“…Table S1 in the Supplementary Materials , presents a comparison of graphene-based gas sensors for NO 2 detection at room temperature. To prove the feasibility of the wearable NFC tag system developed during this work, graphene decorated with 5 wt.% zinc oxide (ZnO) was used due to the previous experience of our research group working with a combination of these materials [ 25 ]. The authors compared different wt.% ZnO loading on a graphene-based sensor and concluded that the 5 wt.% loading performs better than higher and lower loadings according to sensing capabilities toward NO 2 concentrations.…”