Synthesis of ZnO Flakes on Flexible Substrate and Its Application on Ethylene Sensing at Room Temperature

Abstract

As a hormone that determinates the level of fruit ripeness, ethylene concentration monitoring plays an important role in the agricultural field. One of the techniques that can be used to detect ethylene concentration is the sensing method. Zinc oxide (ZnO) is a multipurpose metal oxide semiconductor with a wide application in sensing area. Here, we use a ZnO-based flexible sensor to identify the presence of ethylene gas at certain concentrations. The as-synthesized ZnO layers were deposited on a polyethylene terephthalate-indium doped tin oxide (PET-ITO) flexible substrate using a simple electrochemical deposition method. To enhance the performance of the ethylene sensor, a small amount of silver (Ag) was added to the seeding solution. From the study, it was revealed that the ZnO-Ag layers were able to identify the presence of ethylene gas at the lowest concentration of 29 ppm. The most optimal result was obtained using 1 mM Ag. This layer demonstrated a response of 17.2% and 19.6% of ethylene gas at concentrations of 29 and 50 ppm, with recovery times of four and eight minutes, respectively.

Nickel nanoparticle-decorated reduced graphene oxide/WO3 nanocomposite – a promising candidate for gas sensing

“…When considering the possible mechanism of the influence of nickel on the sensory properties of the Ni/rGO/WO 3 composite, in addition to selective catalytic activity, it is also possible to refer to the existing explanation for the interaction of clusters of metal particles with a semiconductor. In accordance with the literature data, the role of nickel in increasing the sensory sensitivity is most likely associated with the spillover effect [60,61]. When interacting with a gas atom, the barrier height at the Ni/rGO interface decreases due to this effect (the possibility of electron transfer from nickel particles to rGO and WO 3 ), which leads to a greater decrease in the resistance of the composite.…”

Recent Advances in ZnO Based Electrochemical Ethylene Gas Sensors for Evaluation of Fruit Maturity

“…This improvement is due to the phenomenon of surface plasmon resonance (SPR) on the sensor surface. The SPR phenomenon enhances the O 2 absorption process on the surface and eventually helps to achieve fast response and recovery times [52]. This scheme of enhanced performance has been depicted in Fig.…”

“…Their work reported gas sensing at 15 ppm level [51]. ZnO in the form of nanofiber (1D) [57], nanosheet (2D) [58,59], and microspheres (3D) [60,61] have been also reported as sensing elements for detecting gases. For instance, Du et al [57] reported 1D ZnO nanofiber for sensing acetone with a sensitivity of 125Ra/Rg and a response time of 75 s@100 ppm.…”

A Review of Microwave Synthesis of Zinc Oxide Nanomaterials: Reactants, Process Parameters and Morphologies

“…In optoelectronics, various ZnO nanostructures are used for producing e.g., refractive index sensors [ 123 ], surface-enhanced Raman scattering (SERS) sensors [ 124 ], lasers, UV detectors, and UV diodes [ 74 , 125 , 126 , 127 , 128 ]. ZnO nanostructures may serve for producing sensors of gases [ 129 , 130 , 131 , 132 , 133 , 134 , 135 , 136 , 137 , 138 , 139 , 140 , 141 , 142 , 143 , 144 , 145 , 146 , 147 , 148 , 149 , 150 , 151 , 152 ] such as steam (humidity, H 2 O) [ 133 ], ammonia (NH 3 ) [ 129 , 130 , 131 , 143 ], nitrogen (N 2 ) [ 131 ], nitrogen monoxide (NO) [ 129 , 130 , 139 ], nitrogen dioxide (NO 2 ) [ 129 , 131 , 134 , 135 , 136 ,…”