Nanoscale Au-ZnO Heterostructure Developed by Atomic Layer Deposition Towards Amperometric H2O2 Detection

Abstract

Nanoscale Au-ZnO heterostructures were fabricated on 4-in. SiO 2 /Si wafers by the atomic layer deposition (ALD) technique. Developed Au-ZnO heterostructures after post-deposition annealing at 250°C were tested for amperometric hydrogen peroxide (H 2 O 2) detection. The surface morphology and nanostructure of Au-ZnO heterostructures were examined by field emission scanning electron microscopy (FE-SEM), Raman spectroscopy, atomic force microscopy (AFM), X-ray photoelectron spectroscopy (XPS), etc. Additionally, the electrochemical behavior of Au-ZnO heterostructures towards H 2 O 2 sensing under various conditions is assessed by chronoamperometry and electrochemical impedance spectroscopy (EIS). The results showed that ALD-fabricated Au-ZnO heterostructures exhibited one of the highest sensitivities of 0.53 μA μM −1 cm −2 , the widest linear H 2 O 2 detection range of 1.0 μM-120 mM, a low limit of detection (LOD) of 0.78 μM, excellent selectivity under the normal operation conditions, and great long-term stability. Utilization of the ALD deposition method opens up a unique opportunity for the improvement of the various capabilities of the devices based on Au-ZnO heterostructures for amperometric detection of different chemicals.

Dual Transduction of H2O2 Detection Using ZnO/Laser-Induced Graphene Composites

“…Table 2 displays a summary of the sensing figures of merit for the here studied sensors, as well as a comparison with those reported in the literature for ZnO-based H 2 O 2 sensors. As above-mentioned, PL sensing is scarcely used in this type of sensor, whereas transduction via electrochemical assessment using ZnO and ZnO-based composites is far more common [113][114][115][116][117][118][119]. A brief literature comparison from recently published papers revealed that the values obtained for the sensitivity in the present samples were superior to most of those reported for ZnO-based electrodes [117][118][119][120].…”

Plasma-induced sub-10 nm Au-SnO2-In2O3 heterostructures fabricated by atomic layer deposition for highly sensitive ethanol detection on ppm level

“…Among all fabrication techniques mentioned above, ALD or PE-ALD is a thin-film deposition method based on alternating, self-limiting chemical reactions between the gaseous precursors and solid substrate surface [26]. It can produce high quality, uniform and conformal SE even at the low fabrication temperatures [13,28,[31][32][33][34][35]. This technique enables precise control over the thickness, composition and structure (inter-mixed and/or laminated) of SE [29].…”

“…This technique enables precise control over the thickness, composition and structure (inter-mixed and/or laminated) of SE [29]. The ALD fabrication of SnO 2 nano-films for SE of various sensors was previously reported [28,[31][32][33][34][35]. However, special recipe for ALD process must be developed for SE with high aspect ratio and thickness less than 5.0 nm on the wafer scale [33].…”

“…However, special recipe for ALD process must be developed for SE with high aspect ratio and thickness less than 5.0 nm on the wafer scale [33]. Such recipe secures careful selection of the deposition temperature, partial pressures of reactants and pulse and purge durations for the grains size stability and uniformity of ultra-thin monolayers [34]. Thus, most of the developed ALD recipes represent valuable know-how because they ensure highly repeatable and reproducible processes on the semiindustrial scale [35].…”

Layer-by-Layer Films with CoFe2O4Nanocrystals and Graphene Oxide as a Sensitive Interface in Capacitive Field-Effect Devices

“…Research on nanostructured systems for sensing applications is attractive to investigate the detection of many substances. For instance, detection toward hydrogen peroxide and heavy metals is of great relevance for environmental monitoring. − The monitoring of these compounds is important since they are considered as pollutants and toxic substances at determined concentrations. , Hydrogen peroxide is a well-known substance with oxidant properties, which has been employed as a mediator in industries for food and environmental products. − Also, H 2 O 2 is a product generated from several enzymatic reactions. − Chemiluminescence and spectrophotometry are traditional methods for detecting H 2 O 2 ; however, such methods are laborious and time-consuming. , Heavy metals are nonbiodegradable materials and highly toxic for human health and the environment. ,, Such metals react with proteins, forming bonds with thiol groups, and alter the biochemical life cycle of cells . Particularly, copper is a heavy metal present in living organisms at lower concentrations of ca.…”