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We investigated the crystalline phase and electronic structure of perovskite-type La1−xSrxMnO3 (0.0 ≤x≤ 1.0) (LSMx) catalysts synthesized via the citric sol–gel route, for H2O2 reduction. The resulting materials were characterized by XRD, XANES, TR-XANES, and TPO and, after calcination, consisted of cubic perovskite for 0.0 ≤x≤ 0.8 and hexagonal perovskite for x = 1.0. Mn species in the precalcined catalysts were oxidized to Mn3+ for x = 0.0 to 0.6 and to Mn2+ for x = 0.8 and 1.0. After calcination, Mn species were present in a mixed oxidation state of Mn3+/Mn4+, while Sr2+ and La3+ were not altered. TR-XANES and TPO showed that Mn species were oxidized at 210–220 °C and formed active perovskites LSM0.4 and LSM0.0 at 580 °C and 640 °C. This shows that Sr doping can reduce the oxidation temperature of LSMx with 0.2 ≤x≤ 0.4. However, the concentration of Mn4+ in LSMx is increased which is useful for enhancing their catalytic activity and stability. When tested in an alkaline electrolyte, LSM0.6 containing the optimum Mn4+/Mn3+ ratio promoted the formation of hydroxyl via the oxygen intercalation reaction and exhibited low polarization resistance and the highest catalytic activity for H2O2 reduction. [ABSTRACT FROM AUTHOR]

Local structure of indium oxynitride thin films grown on silicon substrates was investigated by X-ray absorption fine structure technique incorporated with first principle calculations. The thin films were grown by using reactive gas timing radio frequency (RF) magnetron sputtering technique with nitrogen (N2) and oxygen (O2) as reactive gasses. The reactive gasses were interchangeably fed into sputtering system at five different time intervals. The gas feeding time intervals of N2:O2 are 30 : 0, 30 : 5, 30 : 10, 30 : 20 and 10 : 30 s, respectively. The analysis results can be divided into three main categories. Firstly, the films grown with 30 : 0 and 30 : 5 s gas feeding time intervals are wurtzite structure indium nitride with 25 and 43% oxygen contaminations, respectively. Secondary, the film grown with 10 : 30 s gas feeding time intervals is bixbyite structure indium oxide. Finally, the films are alloying between indium nitride and indium oxide for other growth condition. The fitted radial distribution spectra, the structural parameters and the combination ratios of the alloys are discussed. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Abstract: This work reports the fabrication and electrochemical characterization of the polydimethylsiloxane (PDMS) microfluidic three-electrode cell chip utilizing diamond-like carbon (DLC) films as a working electrode for amperometric biosensing applications. The DLC films are prepared by a radio-frequency plasma enhanced chemical vapor deposition (RF-PECVD) technique with CH4 as a carbon precursor gas. Raman spectroscopy is employed to characterize the film structures. Cyclic voltammetry is used to investigate the responses of a standard redox species (K3Fe(CN)6 in KNO3) at the three-electrode system. Immobilization of glucose oxidase at the DLC surfaces is attempt through a covalent linkage. Preliminary results indicate that a mediator-free amperometric detection of glucose can be achieved with this device. [Copyright &y& Elsevier]

High sensitivity and very low drift rate pH sensors are successfully prepared by using nanocrystal-TiO2 as sensing membrane of ion sensitive field effect transistor (ISFET) device fabricated via CMOS process. This paper describes the physical properties and sensing characteristics of the TiO2 membrane prepared by annealing Ti and TiN thin films that deposited on SiO2/p-Si substrates through reactive DC magnetron sputtering system. The X-ray diffraction, scanning electron microscopy and Auger electron spectroscopy were used to investigate the structural and morphological features of deposited films after they had been subjected to annealing at various temperatures. The experimental results are interpreted in terms of the effects of amorphous-to-crystalline phase transition and subsequent oxidation of the annealed films. The electrolyte–insulator–semiconductor (EIS) device incorporating Tih name="sbnd" />N membrane that had been obtained by annealing of TiN thin film at 850°C exhibited a higher sensitivity (57mV/pH), a higher linearity (1), a lower hysteresis voltage (1mV in the pH cycle of 7→4→7→10→7), and a smaller drift rate (0.246mV/h) than did those devices prepared at the other annealing temperatures. Furthermore, this pH-sensing device fabrication process is fully compatible with CMOS fabrication process technology. [ABSTRACT FROM AUTHOR]

Surface enhanced Raman spectroscopy (SERS) has been widely studied and recognized as a powerful label-free technique for trace chemical analysis. However, its drawback in simultaneously identifying several molecular species has greatly limited its real-world applications. In this work, we reported a combination between SERS and independent component analysis (ICA) to detect several trace antibiotics which are commonly used in aquacultures, including malachite green, furazolidone, furaltadone hydrochloride, nitrofurantoin, and nitrofurazone. The analysis results indicate that the ICA method is highly effective in decomposing the measured SERS spectra. The target antibiotics could be precisely identified when the number of components and the sign of each independent component loading were properly optimized. With SERS substrates, the optimized ICA can identify trace molecules in a mixture at a concentration of 10 -6 M achieving the correlation values to the reference molecular spectra of 71-98%. Furthermore, measurement results obtained from a real-world sample demonstration could also be recognized as an important basis to suggest this method is promising for monitoring antibiotics in a real aquatic environment., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

The sudden outburst of Coronavirus disease 19 or COVID-19 has raised serious awareness about viral contamination on the environment, which is one of the major causes of the disease. Transmission via contaminated surfaces has been recognized as a significant route for spreading the virus. To suppress and control the spread of SARS-CoV-2, potent virucidal finishing agents for decontamination of medical textiles are urgently required. In this study, an environmental-friendly, economical, non-toxic, and practical finishing on medical textiles with potent virucidal activity was proposed with the combined concepts of a new green synthesis of TiO 2 @Ag core-shell nanostructures using ascorbic acid reduction and UV-curing process. In order to evaluate efficiency of virucidal activity, effects of the amount of TiO 2 @Ag NPs and contact time were determined against the coronavirus following ISO 18184:2019 standard. The finishing agent exhibited an excellent 99.9% virucidal efficacy. The stability of virucidal activity and mechanical properties were determined under repeated washing. The finished fabrics had the ability to retain their virucidal activity and tensile strength through 20 washes. The results suggested that the finishing agent had great potential as a potent and non-toxic virucide against the coronavirus for medical textile applications., Competing Interests: Declaration of conflicting interests: The author(s) declared no potential conflicts of interest with respect to the research, authorship, and/or publication of this article., (© The Author(s) 2022.)

Since the innovation of our new half-piece elastometric respirator, this type of filtering facepiece respirator (FFR) has been used widely in Thailand. Decontamination methods including ultraviolet C (UVC) germicidal irradiation and 70% alcohol have been implemented to decontaminate these respirators. We then examined the inactivation potential of different decontamination processes on porcine epidemic diarrhea virus (PEDV) and numerous bacterial strains, most of which were skin-derived. To enable rigorous integrity of the masks after repeated decontamination processes, fit tests by the Bitrex test, tensile strength and elongation at break were also evaluated. Our results showed that UVC irradiation at a dose of 3 J/cm2 can eradicate bacteria after 60 min and viruses after 10 min. No fungi were found on the mask surface before decontamination. The good fit test results, tensile strength and elongation at break were still maintained after multiple cycles of decontamination. No evidence of physical degradation was found by gross visual inspection. Alcohol (70%) is also an easy and effective way to eradicate microorganisms on respirators. As the current pandemic is expected to continue for months to years, the need to supply adequate reserves of personnel protective equipment (PPE) and develop effective PPE reprocessing methods is crucial. Our studies demonstrated that the novel silicone mask can be safely reprocessed and decontaminated for many cycles by UVC irradiation, which will help ameliorate the shortage of important protective devices in the COVID-19 pandemic era., Competing Interests: The authors have declared that no competing interests exist.

In the present study, indium tin oxide (ITO) nanorod films were produced by usage of ion-assisted electron-beam evaporation with a glancing angle deposition technique. The as-produced ITO nanorod films were annealed in the temperature range of 100-500 °C for two hours in a vacuum atmosphere. The as-produced ITO nanorod films exhibited (222) and (611) preferred orientations from the X-ray diffraction pattern. After vacuum annealing at 500 °C, the ITO nanorod films demonstrated many preferred orientations and the improvement of film crystallinity. The sheet resistance of the as-produced ITO nanorod films was 11.92 Ω/ and was found to be 13.63 Ω/ by annealing at 500 °C. The as-produced and annealed ITO nanorod films had a rod diameter of around 80 nm and transmittance in a visible zone of around 90%. The root mean square roughness of the as-produced ITO nanorod film's surface was 5.49 nm, which increased to 13.77 nm at an annealing temperature of 500 °C. The contact angle of the as-produced ITO nanorod films was 110.9° and increased to 116.5° after annealing at 500 °C.

As fast human temperature screening is needed in large public areas, this paper proposes a low-cost mobile platform module that combines the advantages of analyzing visible and thermal images. In particular, the key idea relies on face detection in the visible image. Then the coordinates of all faces detected are mapped on to the thermal image to determine their corresponding temperatures. Internal temperature compensation and external reference temperature also are employed to reduce the unwanted temperature fluctuation inside the module and in the surrounding environment. Our mobile platform module, called $\unicode{x00B5} {\rm Therm}$, uses a FLIR ONE camera as our visible and thermal imaging cameras. It can simultaneously determine the temperatures of nine people at a speed of 8 frames/second. A field test operation was performed for four days with 1,170 people, with very promising results of 100% sensitivity, 92.6% specificity, and 92.7% accuracy.

This work aims to utilize diamond-like carbon (DLC) thin films for bioreceptor immobilization and amperometric biosensing in a microfluidic platform. A specific RF-PECVD method was employed to prepare DLC thin film electrodes with desirable surface and bulk properties. The films possessed a relatively high sp 2 fraction, a moderate electrical conductivity (7.75 × 10 -3 S cm -1 ), and an optical band gap of 1.67 eV. X-ray photoelectron spectroscopy (XPS) and attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy revealed a presence of oxygen-containing functional groups on the DLC surface. The DLC electrodes were integrated into polydimethylsiloxane (PDMS) microfluidic electrochemical cells with the channel volume of 2.24 μL. Glucose oxidase (GOx) was chosen as a model bioreceptor to validate the employment of DLC electrodes for bioelectrochemical sensing. In-channel immobilization of glucose oxidase (GOx) at the DLC surface was realized through carbodiimide covalent linkages. Enzyme bound DLC electrode was confirmed with the redox potential at around -79 mV vs NHE in 0.1 M phosphate buffer pH 7.4. Amperometric flow-injection glucose sensing at a potential of -0.45 V vs Ag in the absence of standard redox mediators showed the increase of current response upon increasing the glucose concentration. The sensing mechanism is based on the reduction process of H 2 O 2 liberated from the enzymatic activity. The proposed model for the catalytic H 2 O 2 reduction to H 2 O on DLC electrodes was attributed to the dissociation of C-O bonds at the DLC surface.

In this research, β -FeSi₂ films were formed on Si(111) wafer substrates via the utilization of facingtargets direct-current sputtering (FTDCS). The sputtering pressure was set at 1.33×10 -1 Pa and the substrate temperature was maintained at 600 °C. After formation, the as-formed β -FeSi₂ films were transferred to the annealing system and annealed for two hours in a vacuum at 200, 400, and 600 °C. The peaks of the Raman line were located at positions of 194 and 247 cm -1 , which affirmed the formation of the β phase for the as-produced FeSi₂ films. These peak positions were not changed significantly by annealing. FESEM imagery of the as-formed β -FeSi₂ films exhibits a large amount of crystallite with an average grain size of 114.11 nm, including many grain boundaries and a porous area. After annealing, the porosity of the film surface was diminished and grain size was expanded. The rms roughness of the as-formed β -FeSi₂ films was 2.02 nm, which changed slightly after annealing. The average contact angle between the water droplet and as-formed β -FeSi₂ film surface was found to be 93.25°. This result showed that the surface of the unannealed β -FeSi₂ films was hydrophobic. The average contact angle value decreased to 82.15° at an annealing temperature of 600 °C. The hardness of the β -FeSi₂ film surface was 37.55 GPa and 64.88 GPa in cases of non-annealing and annealing temperatures of 600 °C, respectively.

Nanocrystalline iron disilicide (NC-FeSi₂) films were created at room temperature by facing-target direct current sputtering. The NC-FeSi₂ films were annealed at different temperatures of 300 °C, 600 °C, and 900 °C under high vacuum for 2 hours. XRD results of the as-created NC-FeSi₂ films after annealing at 300 °C showed a broad peak at 2  ranging from 40° to 50°. NC-FeSi₂ films annealed at 600 and 900 °C consisted of several preferred orientations with improved crystallinity. Peaks of Raman lines for unannealed and annealed NC-FeSi₂ films were observed at approximately 176 and 232 cm -1 , respectively. Based on FESEM micrographs in plane view, unannealed NC-FeSi₂ films were composed of many small uniform crystallites with diameters of 5-7 nm. At an annealing temperature of 300 °C the small uniform crystallites merged and formed small nanocrystalline clusters, while at annealing temperatures higher than 300 °C they grouped together as large clusters. An AFM of unannealed NC-FeSi₂ films showed a very smooth surface with a root mean square roughness of 0.81 nm which increased by annealing. Unannealed NC-FeSi₂ film surface exhibited an average contact angle of 100.1°, which was hydrophobic. At an annealing temperature of 300 °C, the film surface exhibited the highest contact angle of 106.2°. Average contact angles decreased at annealing temperatures higher than 300 °C.

Indium tin oxide (ITO) nanorod films were deposited onto glass slides and Si wafers using ionassisted electron beam evaporation with a glancing angle deposition technique. The annealing influence on the basic properties of the as-deposited ITO nanorod films was studied in the range of 100-500 °C for two hours in air. The crystallinity of the ITO nanorod films was enhanced with the increasing annealing temperature, and the average transmission of the as-deposited ITO nanorod films in the visible range was 90%. This value did not change significantly after the annealing process. The optical bandgap of the as-deposited ITO nanorod films was 3.94 eV and increased slightly after annealing. The sheet resistance of the as-deposited ITO nanorod films was 12.9 Ω/ and increased to 57.8 Ω/ at an annealing temperature of 500 °C. The as-deposited ITO nanorod films showed nanorod structures with average diameters of 79 nm, which changed slightly with the annealing temperature. The root mean square roughness of the as-deposited ITO nanorod films was 7.9 nm and changed slightly with annealing. The as-deposited ITO nanorod films had an average contact angle of 110.9°, which decreased to 64.2° at an annealing temperature of 500 °C. The experimental results showed that varying the annealing temperature influenced the structural, electrical and wettability properties of the ITO nanorod films while the optical properties and surface morphology were almost unaffected.

Here, we demonstrate a novel device structure design to enhance the electrical conversion output of a triboelectric device through the piezoelectric effect called as the piezo-induced triboelectric (PIT) device. By utilizing the piezopotential of ZnO nanowires embedded into the polydimethylsiloxane (PDMS) layer attached on the top electrode of the conventional triboelectric device (Au/PDMS-Al), the PIT device exhibits an output power density of 50 μW/cm 2 , which is larger than that of the conventional triboelectric device by up to 100 folds under the external applied force of 8.5 N. We found that the effect of the external piezopotential on the top Au electrode of the triboelectric device not only enhances the electron transfer from the Al electrode to PDMS but also boosts the internal built-in potential of the triboelectric device through an external electric field of the piezoelectric layer. Furthermore, 100 light-emitting diodes (LEDs) could be lighted up via the PIT device, whereas the conventional device could illuminate less than 20 LED bulbs. Thus, our results highlight that the enhancement of the triboelectric output can be achieved by using a PIT device structure, which enables us to develop hybrid nanogenerators for various self-power electronics such as wearable and mobile devices.

Carbon-based photoluminescent nanodot has currently been one of the promising materials for various applications. The remaining challenges are the carbon sources and the simple synthetic processes that enhance the quantum yield, photostability and biocompatibility of the nanodots. In this work, the synthesis of blue photoluminescent carbon nanodots from limeade via a single-step hydrothermal carbonization process is presented. Lime carbon nanodot (L-CnD), whose the quantum yield exceeding 50% for the 490nm emission in gram-scale amounts, has the structure of graphene core functionalized with the oxygen functional groups. The micron-sized flake of the as-prepared L-CnD powder exhibits multicolor emission depending on an excitation wavelength. The L-CnDs are demonstrated for rapidly ferric-ion (Fe(3+)) detection in water compared to Fe(2+), Cu(2+), Co(2+), Zn(2+), Mn(2+) and Ni(2+) ions. The photoluminescence quenching of L-CnD solution under UV light is used to distinguish the Fe(3+) ions from others by naked eyes as low concentration as 100μM. Additionally, L-CnDs provide exceptional photostability and biocompatibility for imaging yeast cell morphology. Changes in morphology of living yeast cells, i.e. cell shape variation, and budding, can be observed in a minute-period until more than an hour without the photoluminescent intensity loss., (Copyright © 2016 Elsevier B.V. All rights reserved.)

We investigated the crystalline phase and electronic structure of perovskite-type La1-xSrxMnO3 (0.0 ≤ x ≤ 1.0) (LSMx) catalysts synthesized via the citric sol-gel route, for H2O2 reduction. The resulting materials were characterized by XRD, XANES, TR-XANES, and TPO and, after calcination, consisted of cubic perovskite for 0.0 ≤ x ≤ 0.8 and hexagonal perovskite for x = 1.0. Mn species in the precalcined catalysts were oxidized to Mn(3+) for x = 0.0 to 0.6 and to Mn(2+) for x = 0.8 and 1.0. After calcination, Mn species were present in a mixed oxidation state of Mn(3+)/Mn(4+), while Sr(2+) and La(3+) were not altered. TR-XANES and TPO showed that Mn species were oxidized at 210-220 °C and formed active perovskites LSM0.4 and LSM0.0 at 580 °C and 640 °C. This shows that Sr doping can reduce the oxidation temperature of LSMx with 0.2 ≤ x ≤ 0.4. However, the concentration of Mn(4+) in LSMx is increased which is useful for enhancing their catalytic activity and stability. When tested in an alkaline electrolyte, LSM0.6 containing the optimum Mn(4+)/Mn(3+) ratio promoted the formation of hydroxyl via the oxygen intercalation reaction and exhibited low polarization resistance and the highest catalytic activity for H2O2 reduction.

The need of mobile microscope is escalating as well as the demand of high quality optical components in low price. We report here a novel needle moving technique to fabricate milli-size lens together with thermal assist moldless method. Our proposed protocol is able to create a high tensile strength structure of the lens and its base which is beneficial for exploiting in convertinga smart phone to be a digital microscope. We observe that no bubble trapped in a lens when this technique is performed which can overcome a challenge problem found in a typical dropping technique. We demonstrate the symmetry, smoothness and micron-scale resolution of the fabricated structure. This proposed technique is promising to serve as high quality control mass production without any expensive equipment required.

In this work, we report an ultrasensitive hydrogen (H2) sensor based on tungsten trioxide (WO3) nanorods decorated with platinum (Pt) nanoparticles. WO3 nanorods were fabricated by dc magnetron sputtering with a glancing angle deposition (GLAD) technique, and decorations of Pt nanoparticles were performed by normal dc sputtering on WO3 nanorods with varying deposition time from 2.5 to 15 s. Crystal structures, morphologies, and chemical information on Pt-decorated WO3 nanorods were characterized by grazing-incident X-ray diffraction, field-emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, and photoelectron spectroscopy, respectively. The effect of the Pt nanoparticles on the H2-sensing performance of WO3 nanorods was investigated over a low concentration range of 150-3000 ppm of H2 at 150-350 °C working temperatures. The results showed that the H2 response greatly increased with increasing Pt-deposition time up to 10 s but then substantially deteriorated as the deposition time increased further. The optimally decorated Pt-WO3 nanorod sensor exhibited an ultrahigh H2 response from 1530 and 214,000 to 150 and 3000 ppm of H2, respectively, at 200 °C. The outstanding gas-sensing properties may be attributed to the excellent dispersion of fine Pt nanoparticles on WO3 nanorods having a very large effective surface area, leading to highly effective spillover of molecular hydrogen through Pt nanoparticles onto the WO3 nanorod surface.