ZnO microparticles, ZnO nanoparticles and Zn0.9Cu0.1O nanoparticles toward ethanol vapor sensing: A comparative study

Karimi, Mohammad; Ezzati, Milad; Akbari, Sedyghe; Lejbini, M. Behtaj

doi:10.1016/j.cap.2013.07.014

Cited by 12 publications

(11 citation statements)

References 39 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Allthough all sensors demonstrated good sensing capabilities towards NH 3 over the concentration range of interest, Pd-doping significantly enhanced the NH 3 response, with the sensor containing 0.75 mol% Pd-loaded ZnO NPs-based sensor exhibiting the highest response as compared to the rest of the sensors. It has been previously reported that the response of an SMO-based sensor, such as ZnO, can be empirically expressed as:where C represents the concentration of NH 3 , while a and b are constants defining the type of gas sensor and sensing material employed 20,26,36 . In this case, the value b relies on the charged state of the chemisorbed oxygen species, and can be either 0.5 ( O 2− ) or 1 ( O − ), depending on the surface interactions taking place between the NH 3 molecules and the chemisorbed oxygen species 20,36 .…”

Section: Resultsmentioning

confidence: 99%

A highly responsive NH3 sensor based on Pd-loaded ZnO nanoparticles prepared via a chemical precipitation approach

Mhlongo

Motaung

Cummings

et al. 2019

Sci Rep

103

View full text Add to dashboard Cite

The gas-detecting ability of nanostructured ZnO has led to significant attention being paid to the development of a unique and effective approach to its synthesis. However, its poor sensitivity, cross-sensitivity to humidity, long response/recovery times and poor selectivity hinder its practical use in environmental and health monitoring. In this context, the addition of noble metals, as dopants or catalysts to modify the ZnO surface has been examined to enhance its sensing performance. Herein, we report preparation of Pd-loaded ZnO nanoparticles via a chemical precipitation approach. Various Pd loadings were employed to produce surface-modified ZnO nanostructure sensors, and their resulting NH 3 sensing capabilities both in dry and humid environments were investigated. Through a comparative gas sensing study between the pure and Pd-loaded ZnO sensors upon exposure to NH 3 at an optimal operating temperature of 350 °C, the Pd-loaded ZnO sensors were found to exhibit enhanced sensor responses and fast response/recovery times. The influence of Pd loading and its successful incorporation into ZnO nanostructure was examined by X-ray diffraction, high resolution-transmission electron microscopy, and X-ray photoelectron spectroscopy. XPS studies demonstrated that in all samples, Pd existed in two chemical states, namely Pd° and Pd 2+ . The possible sensing mechanism related to NH 3 gas is also discussed in detail.

show abstract

Section: Resultsmentioning

confidence: 99%

A highly responsive NH3 sensor based on Pd-loaded ZnO nanoparticles prepared via a chemical precipitation approach

Mhlongo

Motaung

Cummings

et al. 2019

Sci Rep

103

View full text Add to dashboard Cite

show abstract

“…Electronic conductivity of Cu is very high and it is cheap and highly available on Earth's crust and so it is important metal for doping [17]. The doping of Cu in ZnO is expected to modify absorption, and other physical or chemical properties of ZnO [18] [19].…”

Section: Introductionmentioning

confidence: 99%

Synthesis of Cu Doped ZnO Nanoparticles: Crystallographic, Optical, FTIR, Morphological and Photocatalytic Study

Labhane¹,

Huse²,

Patle³

et al. 2015

MSCE

View full text Add to dashboard Cite

Nanoparticles of Zn1−xCuxO system with nominal compositions x = 0.0, 0.01, 0.02 and 0.03 were prepared by co-precipitation method at room temperature. Structural, morphological, optical and chemical species of grown crystals were investigated by X-ray diffraction (XRD) technique, Scanning Electron Microscopy (SEM), UV-visible and FTIR spectroscopy, respectively. XRD analysis confirms that all samples have hexagonal structure with no impurity phases which suggest that Cu ion successfully incorporated into the regular ZnO crystal structure. The lattice parameters, volume of unit cell, X-ray density, atomic packing fraction, c/a ratio, and grain size were calculated from XRD pattern of pure and Cu doped ZnO samples and it was found that the grain size was in the range of 23 nm to 29 nm. The strain in pure and Cu doped ZnO samples was calculated by W-H analysis. Optical properties of Zn1−xCuxO samples were studied by using UV-vis spectrophotometer. Optical absorption spectra show that the band gap decreases with increasing Cu contents. The functional group and chemical interactions of Zn1−xCuxO samples were also determined at various peaks using FTIR data and observed that the functional groups corresponding to the Zn-O bands in the samples. The photocatalytic activities of the samples were investigated by oxidation of methylene blue under UV light illumination in batch reactor. The scavenger study was carried out to find out main reactive species responsible for the degradation of dyes.

show abstract

“…On the surface of ZnO nanoplates, reactive oxygen ions, such as O − 2 , O − and O 2− , are mainly chemisorbed with the aid of thermal energy in the dark. The reactions kinetics can be described as follows [25]:…”

Section: Resultsmentioning

confidence: 99%

“…where the subscripts 'g', 'ads' and 'lat' mean gas, adsorbed and lattice, respectively. These oxygen ions react with ethanol vapour introduced into the glass chamber by the following reaction [25]:…”

Section: Resultsmentioning

confidence: 99%

Enhancement of ethanol-sensing properties of ZnO nanoplates by UV illumination

et al. 2019

View full text Add to dashboard Cite

ZnO nanoplates with hexagonal wurtzite structure were synthesized by hydrothermal treatment. The average dimension and average thickness of the plates were ∼200 × 400 and 40 nm, respectively. ZnO nanoplates were deposited on Pt-interdigitated electrodes for the fabrication of gas-sensing devices. The ethanol-sensing properties of the devices were investigated in the dark vs. ultraviolet (UV) illumination. Under the UV illumination, the optimal operating temperature of the devices can be reduced from 237 to 164 • C and the response of the device was increased from 2.8 to 8.5 towards 1500 ppm ethanol vapour.

show abstract

ZnO microparticles, ZnO nanoparticles and Zn0.9Cu0.1O nanoparticles toward ethanol vapor sensing: A comparative study

Cited by 12 publications

References 39 publications

A highly responsive NH3 sensor based on Pd-loaded ZnO nanoparticles prepared via a chemical precipitation approach

A highly responsive NH3 sensor based on Pd-loaded ZnO nanoparticles prepared via a chemical precipitation approach

Synthesis of Cu Doped ZnO Nanoparticles: Crystallographic, Optical, FTIR, Morphological and Photocatalytic Study

Enhancement of ethanol-sensing properties of ZnO nanoplates by UV illumination

Contact Info

Product

Resources

About