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The harsh environment of space, especially radiation of direct solar rays, can potentially raise the temperature of the spacecraft to harmful levels. Thermal control coatings (TCCs) fix the thermal condition of the spacecraft acceptable for its components. This is possible by diffusely reflecting all effective ultraviolet (UV), visible (VIS) and near infrared (IR) (NIR) wavelengths of solar radiation and emmition of IR energy. The most commonly used TCCs have used ZnO as a pigment, but absorption of the UV light by ZnO pigment can change the ideal condition of these TCCs. The aim of his study is the using the porous ZnO particles as pigment to prevent the UV absorption.

To enhance the efficiency of these coatings, in the present study, nano-porous zinc oxide particles were synthesized and used as pigments for white TCCs.

The results revealed that the proposed TCC (TPZ), Thermal control coating with porous ZnO had better reflection (scattering) and emittance properties in comparison with the coating using ZnO as a pigment (TZ coating); so this coating had a solar absorptance value equal to 0.141, whereas this value for TZ was 0.150. Furthermore, TPZ showed higher thermal emittance (0.937) in comparison with TZ (0.9). These changes were because of the improvement in the refractive index, shape and surface area of the pigments. The general trend of the scattering coefficients for the prepared coating, as calculated from the Kubelka–Munk equation, showed that scattering was more efficient in the UV region, as compared with the TCC containing ZnO pigments.

This type of pigment for the first time is evaluated in TCCs.

The purpose of this paper is to synthesize porous zinc oxide (ZnO) by means of strain etching/wet chemical etching method with the use of 0.5% of nitric acid (HNO₃) etchant. The structural and surface morphological properties of the samples are accessed by using X‐ray diffraction (XRD) and scanning electron microscopy (SEM) characterization techniques.

ZnO samples used in this work were deposited on the p‐Si (111) substrates by using radio frequency (RF) sputtering technique. Wet chemical etching processes with the use of 0.5% HNO₃ etchant was applied on these samples in order to obtain porous structure. The porous ZnO samples are characterized by means of XRD and SEM to access their structural and surface morphological properties.

The XRD and SEM cross‐sectional measurements revealed that the thickness of the etched ZnO thin films is proportional to the etching time. SEM micrographs show that the surface morphology of ZnO changes over etching time. On the other hand, XRD results indicate that the crystallite sizes of the ZnO(002) decreases when the etching time increases.

The paper shows how porous ZnO thin films have been successfully synthesized by using simple wet chemical etching. SEM images reveal that this method is reliable when producing porous structure ZnO surfaces.

This work encompasses the various laboratory-based and portable methods evolved in recent times for sensitive and selective detection of ethylene for fruit-ripening application. The role of ethylene in natural and artificial fruit ripening and the associated health hazards are well known. So there is a growing need for ethylene detection. This paper aims to highlight potential methods developed for ethylene detection by various researchers, including ours. Intense efforts by various researchers have been on since 2014 for societal benefits.

The paper focuses on types of sensors, fabrication methods and signal conditioning circuits for ethylene detection in ppm levels for various applications. The authors have already designed, developed a laboratory-based set-up belonging to the electrochemical and optical methods for detection of ethylene.

The authors have developed a carbon nanotube (CNT)-based chemical sensor whose performance is higher than the reported sensor in terms of material, sensitivity and response, the sensor element being multi-walled carbon nanotube (MWCNT) in comparison to single-walled carbon nanotube (SWCNT). Also the authors have developed infrared (IR)-based physical sensor for the first time based on the strong IR absorption of ethylene at 10.6 µm. These methods have been compared with literature based on comparable parameters. The review highlights the potential possibilities for development of portable device for field applications.

The authors have reported new chemical and physical sensors for ethylene detection and quantification. It is demonstrated that it could be used for fruit-ripening applications A comparison of reported methods and potential opportunities is discussed.

To study the effect of rotation of a zinc/steel cylinder couple on the rate of galvanic corrosion in saline water and a saline water methyl alcohol system.

The weight loss technique was used for calculating the rate of corrosion. variables such as cylinder rotational speed, salt concentration, alcohol volume percentage, and zinc/steel ratio were studied.

The relationship of turbulence and the rate of corrosion were found to fit the equation R=aRe 0.27. The presence of methyl alcohol in a saline water system decreased the rate of corrosion between 58 and 72 percent for a volume percentage of alcohol from 20 to 70 percent.

This paper explains the mechanism of galvanic corrosion for a zinc/steel cylinder couple in the turbulent region for saline water and saline water‐alcohol systems.

This paper aims to successfully synthesize three-dimensional spindle-like Au functionalized Co₃O₄-ZnO nanocomposites; characterize the structure, morphology and surface chemical properties of the products; study the effect of Au NPs doping concentration, operating temperature different gas to, sensing properties; and introduce an attractive gas sensor for acetone detection.

Au NPs functionalized Co₃O₄-ZnO nanocomposite was prepared by coprecipitation and impregnation methods; the structure and surface chemical property of the products were characterized by XRD, SEM, TEM, UV-Vis, BET and XPS. The sensing ability of Au@Co₃O₄-ZnO for acetone and mechanism was analyzed systematically.

The results of gas sensing tests show that the unique component structure, Schottky junction and catalytic effect of Au functionalization make it have low operating temperature, excellent selectivity, high response (10 ppm, 56) and rapid response recovery time.

All the characterization and test data of the prepared materials are provided in this paper and reveals the gas sensing mechanism of the gas sensor.

The detection limit is 2.92–100 ppb acetone. It is promising to be applied in low-power, micro detection and miniature acetone gas sensors.

The gas sensor prepared has a lower working temperature and low detection limit, so it has promising application prospects in low-concentration acetone detection and early warning.

The unique component structure, Schottky junction and catalytic effect of Au functionalization Co₃O₄-ZnO make it have low operating temperature, excellent selectivity and rapid response recovery time.

This paper aims to report a novel preparation method of ZnO particles with different structures and their photocatalytic activity.

ZnO powders are prepared by a facile, economical and environment-friendly aqueous solution route. X-ray diffraction, field emission scanning electron microscopy, energy dispersive spectroscopy, transmission electron microscopy and UV-vis diffuse reflectance spectra are used to characterize the products. Photocatalytic activity of the samples is evaluated by degradation of organic pollutant pentachlorophenol under UV-vis irradiation.

It is found that three-dimensional ZnO hierarchical structures can be prepared via aqueous solution route without using any template or structure-directing agent, and the alkalinity of reaction solution is the key factor. All the as-prepared ZnO products have good catalytic activity under UV-vis light irradiation.

This report presents a simple method for the preparation of ZnO particles with excellent photocatalytic activity. Experimental results could provide useful reference for the treatment of chlorophenols in the future.

Zinc oxide (ZnO) is an emerging optoelectronic material due to its various functional behaviors. The purpose of this paper is to report on the fabrication and characterizations of ZnO microrods.

ZnO microrods were synthesized using sol‐gel immerse technique on oxidized silicon (Si) substrates. The oxidized Si substrates were immersed in ZnO aqueous solution for different times ranging from three to five hours. The surface morphologies of the ZnO microrods were examined using scanning electron microscope (SEM). In order to investigate the structural properties, the ZnO microrods were measured using an X‐ray diffractometer (XRD). The optical properties were measured using a photoluminescence (PL) spectrophotometer.

Characterization from SEM shows an enhanced growth of the ZnO rods with increasing immerse time. XRD characterizations demonstrate sharp and narrow diffraction peaks peculiar to ZnO, which implies that the rod is of high crystallinity. Based on the PL spectra, long immerse time results in the high peak in the UV region.

This paper concludes that the immerse time exerts an influence on the ZnO microrods. A longer immerse duration is preferred in the fabrication of the ZnO microrod, which is considered an emerging material for many advanced electronic and optoelectronic applications.

This paper aims at analyzing the potential of new materials in magnesium-ion batteries (MIBs) with a particular focus on options for electrodes and electrolyte solutions while also carefully considering the barriers to their entry in this application for MIBs, with a particular focus on the material options for electrodes and electrolyte solutions.

Potential materials for MIBs were examined for sustainability, safety and efficiency to develop the sustainable and well-working MIBs.

For anode materials, the use of Mg-bismuth alloys has shown promise, whereas Chevrel phases or layered molybdenum disulfide have potential as cathode materials. Potential electrolytes range from traditional materials to the development of tailored solid-state and liquid-based options.

This study considers the growing need for Mg-based ion batteries, as well as the need for suitable electrode and electrolyte materials and analyzes suitable options.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0081/

The purpose of the paper is to investigate photochemical machining characteristics of stainless steel (AISI 304-SS304) parts with a novel design are investigated experimentally from the aspect of process parameters. The effects of phototool pattern geometry, ultraviole (UV) exposure time and etching time on of AISI 304 were evaluated.

The designed semi-automated photochemical manufacturing (PCM) equipment consists of 4 units, which include UV exposure, etching, developing and surface cleaning units. Experimental procedure has been designed via Taguchi method. Results were evaluated via Analysis of Variance (ANOVA) method.

Etching time is the most effective factor in PCM quality of AISI 304 stainless steel. Surface roughness is sensitive to geometrical pattern of the phototool for PCM of AISI 304 UV exposure time is less influential on the PCM quality for stainless steel.

The designed PCM equipment prototype is not fully automated, which requires automation for part replacements into units. The effects of the temperature inside chemical processing units on process characteristics cannot be evaluated due to equipment limitations. The effects of surface cleaning time inside surface cleaning unit are not analyzed.

The utilized PCM equipment is semi-automated equipment, with which the process parameters such as etching time, surface cleaning time, UV exposure time and developing time can be controlled. Different from literature, the effects of phototool pattern geometries on the photochemical machining quality parameters are evaluated for the processing of AISI 304. The effects of processing parameters on dimensional accuracy, which is not common in the literature for AISI 304 stainless steel, are also evaluated.

The purpose of this study is to fabricate an ultraviolet (UV) metal-semiconductor-metal (MSM) photodetector based on zinc oxide nanorods (ZnO NRs) grown on seeded silicon (Si) substrate that was prepared by a low-cost method (drop-casting technique).

The drop-casting method was used for the seed layer deposition, the hydrothermal method was used for the growth of ZnO NRs and subsequent fabrication of UV MSM photodetector was done using the direct current sputtering technique. The performance of the fabricated MSM devices was investigated by current–voltage (I–V) measurements. The photodetection mechanism of the fabricated device was discussed.

Semi-vertically high-density ZnO (NRs) were effectively produced with a preferential orientation along the (002) direction, and increased crystallinity is confirmed by X-ray diffraction analysis. Photoluminescence results show a high UV region. The fabricated MSM UV photodetector showed that the ZnO (NRs) MSM device has great stability over time, high photocurrent, good sensitivity and high responsivity under 365 nm wavelength illumination and 0 V, 1 V, 2 V and 3 V applied bias. The responsivity and sensitivity for the fabricated ZnO NRs UV photodetector are 0.015 A W-1, 0.383 A W-1, 1.290 A W-1 and 1.982 A W-1 and 15,030, 42.639, 100.173 and 334.029, respectively, under UV light (365 nm) illumination at (0 V, 1 V, 2 V and 3 V).

This paper uses the drop-casting technique and the hydrothermal method as simple and low-cost methods to fabricate and improve the ZnO NRs photodetector.