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The chemical solution-deposited zinc ferrite (ZFO; ZnFe2O4) RRAM devices on Pt/Ti/SiO2/Si substrate are being reported. Fabricated devices show the positive as well as negative unipolar switching memory properties. Thickness of ZFO thin films in Au/ZFO/Pt structure was varied to explore the resistive switching behavior. It is reported that forming voltage and resistance of the device increase by increasing the number of ZFO layers. Our results reveal that ZFO thin film deposited by eight times spin coating with a thickness of eight layers illustrates stable resistive switching with the most steady Set (2 V) and Reset voltages (0.5 V) as compared to the devices with two, four, and six layers. It also demonstrates the enhanced endurance of greater than 300 switching cycles and stable time-dependent resistance greater than 104 s. The current transport mechanism is Ohmic at low-resistance state, while it leads to Schottky emission at high-resistance state. The possible switching mechanism is also discussed for the possible application of ZFO-based memory for nonvolatile RRAM devices. [ABSTRACT FROM AUTHOR]

The chemical solution-deposited zinc ferrite (ZFO; ZnFe2O4) RRAM devices on Pt/Ti/SiO2/Si substrate are being reported. Fabricated devices show the positive as well as negative unipolar switching memory properties. Thickness of ZFO thin films in Au/ZFO/Pt structure was varied to explore the resistive switching behavior. It is reported that forming voltage and resistance of the device increase by increasing the number of ZFO layers. Our results reveal that ZFO thin film deposited by eight times spin coating with a thickness of eight layers illustrates stable resistive switching with the most steady Set (2 V) and Reset voltages (0.5 V) as compared to the devices with two, four, and six layers. It also demonstrates the enhanced endurance of greater than 300 switching cycles and stable time-dependent resistance greater than 104 s. The current transport mechanism is Ohmic at low-resistance state, while it leads to Schottky emission at high-resistance state. The possible switching mechanism is also discussed for the possible application of ZFO-based memory for nonvolatile RRAM devices. [ABSTRACT FROM AUTHOR]

Electrochemical anodization, under a constant voltage of 45 V and for 15, 30, and 45 min, was performed to fabricate highly ordered TiO 2 nanotubes. Depending on the processing paramters, the diameter of the TiO 2 nanotubes was found to be around 95 ± 6 nm, while the thickness of TNT layer exhibited a change with anodizing time, varying from 1 to 4 μm. Subsequent to the anodization α-Fe 2 O 3 /TiO 2 heterogeneous structure was created by the spin coating of iron precursor based solutions on TiO 2 nanotubes. X-ray diffraction (XRD) and scanning electron microscopy (SEM) analysis were utilized to ascertain the phase structure and morphology of TiO 2 nanotubes. The change of optical band gap values depending on the processing parameters was calculated using UV–Vis spectrophotometer data. The photocatalytic performances of the samples, namely the degradation rates and kinetics, were evaluated by examining the photodegradation of methylene blue (MB). The (TC15) sample, obtained by anodizing for 15 min and decorated with α-Fe 2 O 3 , exhibited the highest photocatalytic activity, with a degradation efficiency of 70 % at the end of 7 h of light exposure. On the other hand, the inhibition percentages of bacterial growth were examined and it was seen that the TC30 sample with the highest value was 88.89 % for E.coli bacteria and 70.57 % for S.aureus. To assess the mechanism of antimicrobial activity, ROS (Reactive Oxygen Species) Analysis were perfomed on T30 and TC30 groups and the ROS amount of TC30 was higher than T30. According to the results of the L929 mouse fibroblast cytotoxicity experiment with indirect contact according to ISO 10993-5 standards, all samples showed a successful performance in terms of cell viability. The cell viability of TC15 was higher in comparison to the control group. [ABSTRACT FROM AUTHOR]

Photoelectrochemical devices require solid anodes and cathodes for the easy assembling of the whole cell and thus redox catalysts need to be deposited on the electrodes. Typical catalyst deposition involves drop casting, spin coating, doctor blading or related techniques to generate modified electrodes where the active catalyst in contact with the electrolyte is only a very small fraction of the deposited mass. We have developed a methodology where the redox catalyst is deposited at the electrode based on supramolecular interactions, namely CH‐π and π–π between the catalyst and the surface. This generates a very well‐defined catalysts‐surface structure and electroactivity, together with a very large catalytic response. This approach represents a new anchoring strategy that can be applied to catalytic redox reactions in heterogeneous phase and compared to traditional methods involves about 4–5 orders of magnitude less mass deposition to achieve comparable activity and with very well‐behaved electroactivity and stability. [ABSTRACT FROM AUTHOR]

Stable aqueous dispersions of spin-crossover (SCO) doped [FeII(Htrz)2(trz)](BF4) nanoparticles (NPs) were prepared by using water-soluble polyvinylpyrrolidone (PVP) as protecting polymer. The metal or ligand substitution percentage regulated the ultra-small size and morphology of the NPs. At the same time, the colloidal dispersions showed a complete conversion of the LS state to the HS state of the FeII ion. [ABSTRACT FROM AUTHOR]

New anodes consisting of zirconium-doped PbO2 coating, growth on titanium dioxide interlayer, were deposited on titanium substrates using spin coating method and have been tested for the removal of ampicillin, a β-lactam antibiotic, from water. Morphological, structural, and electrochemical properties of the prepared coatings were characterized by scanning electron microscopy (SEM), atomic force microscope (AFM), X-ray diffraction (XRD), and electrochemical impendence spectroscopy (EIS). Results showed that the incorporation of zirconium dopant had a noticeable modification in the morphology of anodes. An increase in the surface roughness and the specific active area were observed with Ti/TiO2/PbO2- 10% Zr electrode compared to other anodes. The electrochemical measurements indicated that the anode doped with 10% Zr showed a more protective coating performance than the undoped and 20% Zr-doped PbO2 electrodes. The experiments on ampicillin degradation revealed that doped lead dioxide anodes have excellent electrocatalytic activity. The major byproduct generated during anodic oxidation treatment has been identified as ampicilloic acid by liquid chromatography-mass spectroscopy (LC–MS) analysis. Results demonstrated that Ti/TiO2/PbO2- 10% Zr anode presents the best removal rate of ampicillin with a minimum intermediate amount, which leads to conclude that 10% is the optimum percentage of zirconium dopant for antibiotic wastewater treatment. [ABSTRACT FROM AUTHOR]

The wide bandgap oxide semiconductor thin films are synthesized using tetrahydroxogallate (III) ammonium {NH4Ga(OH)4} precursor at a concentration of 10 at% Ga and varying amounts of hydrated aluminum nitrate between 0.6 and 3.2 at%. Thin films of β‐Ga2O3:Al are synthesized by spin coating and spray pyrolysis with postannealing in nitrogen ambient at 930 °C. The structural properties of the thin films are investigated using XRD and Raman spectroscopy, while the electrical characteristics are determined using 4‐point probe, current–voltage (I–V), and capacitance–voltage (C–V) measurements with Ti/Al/Ni/Au Ohmic contacts and Pd/Au Schottky contacts. The β‐Ga2O3 with 2.2 at% Al is found to be the optimal concentration in this study, resulting in ideality factors of 1.10 and 1.09, saturation currents of 3.17 × 10−6 and 3.10 × 10−6 A, Schottky barrier heights of 0.73 and 0.88 eV, and series resistances of 948 and 955 Ω, for the spin‐coated and pyrolytically sprayed samples respectively. [ABSTRACT FROM AUTHOR]

Sol-gel spin coating method was employed for depositing TiO2 and Ag-doped TiO2 films. The effects of Ag doping and the annealing temperatures (300–600 °C) were studied with respect to their structural, morphological, vibrational, and optical properties. Field Emission Scanning Electron microscopy (FESEM) investigation exhibited the grained, compact structures of TiO2-based films. Ag incorporation resulted in a rougher film surface. X-ray diffraction (XRD) results confirmed the formation of Ag nanoparticles and AgO phase, along with anatase and rutile TiO2, strongly depending on Ag concentration and technological conditions. AgO fraction diminished after high temperature annealing above 500 °C. The vibrational properties were characterized by Fourier Transform Infrared (FTIR) spectroscopy. It was found that silver presence induced changes in IR bands of TiO2 films. UV–VIS spectroscopy revealed that the embedment of Ag NPs in titania matrix resulted in higher absorbance across the visible spectral range due to local surface plasmon resonance (LSPR). Ag doping reduced the optical band gap of sol-gel TiO2 films. The optical and plasmonic modifications of TiO2:Ag thin films by the number of layers and different technological conditions (thermal and UV treatment) are discussed. [ABSTRACT FROM AUTHOR]

The escalating environmental concerns associated with conventional plastic packaging have accelerated the development of sustainable alternatives, making food packaging a focus area for innovation. Bioplastics, particularly polyhydroxyalkanoates (PHAs), have emerged as potential candidates due to their biobased origin, biodegradability, and biocompatibility. PHAs stand out for their good mechanical and medium gas permeability properties, making them promising materials for food packaging applications. In parallel, zinc oxide (ZnO) nanoparticles (NPs) have gained attention for their antimicrobial properties and ability to enhance the mechanical and barrier properties of (bio)polymers. This review aims to provide a comprehensive introduction to the research on PHA/ZnO nanocomposites. It starts with the importance and current challenges of food packaging, followed by a discussion on the opportunities of bioplastics and PHAs. Next, the synthesis, properties, and application areas of ZnO NPs are discussed to introduce their potential use in (bio)plastic food packaging. Early research on PHA/ZnO nanocomposites has focused on solvent-assisted production methods, whereas novel technologies can offer additional possibilities with regard to industrial upscaling, safer or cheaper processing, or more specific incorporation of ZnO NPs in the matrix or on the surface of PHA films or fibers. Here, the use of solvent casting, melt processing, electrospinning, centrifugal fiber spinning, miniemulsion encapsulation, and ultrasonic spray coating to produce PHA/ZnO nanocomposites is explained. Finally, an overview is given of the reported effects of ZnO NP incorporation on thermal, mechanical, gas barrier, UV barrier, and antimicrobial properties in ZnO nanocomposites based on poly(3-hydroxybutyrate), poly(3-hydroxybutyrate-co-3-hydroxyvalerate), and poly(3-hydroxybutyrate-co-3-hydroxyhexanoate). We conclude that the functionality of PHA materials can be improved by optimizing the ZnO incorporation process and the complex interplay between intrinsic ZnO NP properties, dispersion quality, matrix–filler interactions, and crystallinity. Further research regarding the antimicrobial efficiency and potential migration of ZnO NPs in food (simulants) and the End-of-Life will determine the market potential of PHA/ZnO nanocomposites as active packaging material. [ABSTRACT FROM AUTHOR]

Non-radiative recombination of perovskite solar cells (PSCs) will increase as a result of the numerous crystallographic defects that the solution-grown perovskite films will cause, particularly at the grain boundary and film surface. As a result, it negatively influences the performance of the device. Consequently, lowering perovskite film defects is a useful strategy for raising the efficiency of PSCs. This study reports a grain regeneration and passivation approach that can decrease the recombination loss of the perovskite layer/charge transfer layer interface and the grain border. Guanidine iodide (GAI) treatment of perovskite films is the means by which this objective is accomplished. Unlike most methods that use GAI to post-treatment the perovskite layer or add GAI into the perovskite precursor solution, this work uses GAI for pre-treatment before spin coating the perovskite layer. It can effectively passivate surface defects and increase the grain size of perovskite films by controlling the crystallization process. The water stability of devices was enhanced, the short-circuit current (Jsc), filling factor (FF), and power conversion efficiency (PCE) of PSCs were markedly improved, and non-radiative recombination was successfully reduced. The best efficiency of PSCs was 20.56% after the additional GAI treatment was applied to the perovskite layer, an 11.9% increase over the efficiency of the control device without GAI treatment. This method has the advantage of being simple and straightforward, providing a feasible pathway for the low-cost preparation and commercialization of PSCs. [ABSTRACT FROM AUTHOR]

Polymer matrix composite memristors exhibit exceptional performances, including a straightforward structure, rapid operational speed, high density, good scalability, cost-effectiveness, and superior mechanical flexibility for wearable applications. This study utilizes sensitized chemical evaporation and spin coating carbonization techniques to fabricate composite nanofibers doped with Nickel-Cobalt coated multi-walled carbon nanotubes (SC-NCMTs). A novel polyimide matrix composite memory device was fabricated using in-situ polymerization technology. The transmission electron microscopy (TEM) and micro-Raman spectroscopy analyses validate the presence of dual interfaces structure locating between the Ni-Co-MWNTs, carbon nanofibers and PI matrix and a large number of defects in the SC-NCMTs/PI composite films, resulting in tunable ternary resistive switching behaviors of the composite memory device, exhibiting good ON/OFF current ratio of 104 and a retention time of 2500 s under operating voltages V onset ≤ 3 V. Based on the interface layer distribution and the defects in the composites, different physical models are comprised to investigate the charge transmission mechanism underlying the multilevel resistive switching behaviors. The studies on the impact of tunable multi-interfaces trap structures on multilevel resistive switching could enhance the data storage capabilities of polymer matrix memristors. [ABSTRACT FROM AUTHOR]

AlN/Er 2 O 3 multi-layer coatings, as a novel hydrogen isotope permeation barrier for nuclear reactor and hydrogen energy field, were prepared by magnetron sputtering coupled with metal-organic decomposition on the surface of reduced activation ferrite/martensitic steel. The thickness of the Er 2 O 3 layers was adjusted by spin coating several times, the adhesion of the layers was tested with a micron scratch tester, and the microstructure and surface composition of the layers were analyzed by TEM and XPS. The results indicate the absence of evident crack holes on the coating surface, uniform distribution of elements without segregation, and satisfactory densification. In comparison with the individual Er 2 O 3 coating, the multi-layer coating incorporating AlN as the interlayer exhibits enhanced adhesion strength, which could effectively mitigate the thermal mismatch phenomenon of Er 2 O 3 under high temperature conditions. Electrochemical hydrogen permeation and high temperature gas pressure driven deuterium permeation tests demonstrated that the permeability resistance of the AlN/Er 2 O 3 coating does not linearly increase with its thickness. The hydrogen permeation reduced factor of the coating reaches its maximum value when the thickness of the Er 2 O 3 coating is 1500 nm. [ABSTRACT FROM AUTHOR]

This research work focuses on the potential applications of polypyrrole nanofibers and phosphorus-doped graphene (PPy/P-rGO) in gas sensing devices. The synthesis and characterization of PPy/P-rGO nanocomposites were conducted to assess their suitability for gas sensing applications. The nanocomposites were synthesized using a combination of hydrothermal processing and in situ polymerization methods. Various characterization techniques such as XRD, Raman spectroscopy, FESEM, and HRTEM were employed to analyze the synthesized nanocomposites. The PPy/P-rGO nanocomposite was then used to fabricate gas sensing devices on soda lime substrate through spin coating technique. The sensing behavior of these devices was evaluated in different chemical vapor environments, including ammonia, methanol, ethanol, acetone, and chloroform. The PPy/P-rGO nanocomposite sensor exhibited a response time of 20 s, a recovery time of 57 s, a detection limit of 0.082 ppm (82 ppb), and a sensing response of ~ 460%, which was about 3.96 times greater than the sensing response of the pure PPy sensor (116%), which indicates an effective modification of the PPy device through the addition of P-rGO. The PPy/P-rGO sensor exhibits a remarkably linear gas response when exposed to ammonia concentrations ranging from 1 to 100 ppm. The synergistic effects of PPy and P-rGO demonstrate the potential of these nanocomposites in overcoming challenges faced by gas sensing technologies and developing high-performance devices. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of spinning speed on the electrical, optical, structural, morphological, and gas sensing properties of thin films deposited on glass substrates by sol–gel spin coating, using copper acetate dihydrate as the precursor. The deposition of the films was carried out at varying spinning speeds from 1500 rpm to 2500 rpm to achieve different thicknesses ranging from 157 nm to 470 nm, respectively. The results revealed that the resistivity of the films decreased from 75.5 Ω·m to 42.5 Ω·m with the decrease in spinning speed. X-ray diffraction (XRD) studies demonstrated that the crystallite size varied in the range of 18.14–27.48 nm. The band gap of the samples was found to vary from 2 eV to 1.69 eV, revealing that these samples were suitable for gas sensing applications. Field-emission scanning microscopy (FESEM) studies showed that the prepared samples were porous in nature and were suitable for H2S gas detection. The films were examined at different operating temperatures with different concentrations of H2S gas. The results showed that the response toward hydrogen sulfide gas varied with varying thickness of the samples. The CuO thin films showed the highest response toward hydrogen sulfide gas at a temperature of 25°C. [ABSTRACT FROM AUTHOR]

In this paper, we study the effects of Cu, Ni, and Zn doping in TiO2 layers on the performance of MAPbI3-based perovskite solar cells (PSCs) fabricated under ambient air with relative humidity between 60% and 70%. One of the factors limiting the efficiency of MAPbI3-based PSCs is the TiO2 electron transport layer properties. The efficiency of PSCs is the maximum power that can be produced by a PSC when illuminated by light with a specific energy. This study aims to enhance MAPbI3-based PSC efficiency by doping TiO2 with 2 mol.% Cu, Ni, and Zn. MAPbI3-based PSCs were then fabricated using spin coating with the structure ITO/TiO2/MAPbI3/graphite/ITO. X-ray diffraction and scanning electron microscopy (SEM) analyses revealed that doping reduced TiO2 crystal sizes from 19.34 nm (pure) to 18.96 nm (Cu-doped), 18.04 nm (Ni-doped), and 17.6 nm (Zn-doped), with corresponding average particle sizes of 225 nm, 107 nm, 79 nm, and 50.4 nm. Ultraviolet–visible (UV–Vis) spectroscopy indicated an increase in the bandgap from 3.0 eV (pure) to 3.1 eV (Cu-doped), 3.2 eV (Ni-doped), and 3.25 eV (Zn-doped). Current–voltage (I–V) electrical testing revealed improvement in efficiency from 5.7% (undoped) to 7.6% (Cu-doped), 6.9% (Ni-doped), and 8.01% (Zn-doped). These findings demonstrate that metal-doped TiO2 significantly enhances the efficiency of MAPbI3-based PSCs fabricated in open-air environments without the need for a glove box. [ABSTRACT FROM AUTHOR]

Though 3D printing shows potential in fabricating complex optical components rapidly, its poor surface quality and dimensional accuracy render it unqualified for industrial optics applications. The layer steps in the building direction and the pixelated steps on each layer's contour result in inevitable microscale defects on the 3D‐printed surface, far away from the nanoscale roughness required for optics. This paper reports a customized vat photopolymerization‐based lens printing process, integrating unfocused image projection and precision spin coating to solve lateral and vertical stair‐stepping defects. A precision aspherical lens with less than 1 nm surface roughness and 1 µm profile accuracy is demonstrated. The 3D‐printed convex lens achieves a maximum MTF resolution of 347.7 lp mm−1. A mathematical model is established to predict and control the spin coating process on 3D‐printed surfaces precisely. Leveraging this low‐cost yet highly robust and repeatable 3D printing process, the precision fabrication of multi‐scale spherical, aspherical, and axicon lenses are showcased with sizes ranging from 3 to 70 mm using high clear photocuring resins. Additionally, molds are also printed to form multi‐scale PDMS‐based lenses. [ABSTRACT FROM AUTHOR]

AbstractThe single source precursor tris(N,N,N’,N’-tetramethylethylenediamine)Al(III)Cl3 has been synthesized by the reaction of N,N,N’,N’-tetramethylethylenediamine (TMEDA) with AlCl3 in 3:1 molar ratio in ethanol. The precursor is stable for long periods of time and cleanly generated aluminum nitride upon pyrolysis. The pyrolysis process was optimized by varying parameters such as temperature, pressure, and the flow rate of gases (N2 and Ar). Thin films of AlN were prepared by spin coating the precursor onto Si(100) and quartz substrates followed by pyrolysis under optimized CVD conditions obtained from bulk pyrolysis. Pyrolyzed powders and films were characterized with a variety of techniques. X-ray diffraction (XRD) showed 8.5 nm grain size with a dominant 220 orientation. UV-Vis spectroscopy indicated a band gap for the AlN films of ∼5.7 eV, which is close to bulk AlN (6.1 eV). FESEM showed a smooth and homogeneous film surface and EDAX showed a 1.4:1 ratio of Al:N, respectively. [ABSTRACT FROM AUTHOR]

Dust and other environmentally suspended particles deposited on the solar panels reduce the sunlight to photovoltaic cells, reducing the total energy outcome. A dust-reflecting coating keeps a cleaner surface, thus enhancing light absorption and improving the overall energy outcome. This study synthesized the sol–gel of SiO2, MgF2, and TiO2 and made the coating on the glass substrate by SiO2+MgF2, SiO2+TiO2, and MgF2+SiO2+TiO2 using sol–gel dip coating and spin coating method. Coatings that occurred on the glass sample surfaces were identified by using FTIR analysis. Five of the above six coatings made using different mixtures have increased transmittance than pure glass, while one SiO2+MgF2 spin coating reduced the transmittance. The minimum water contact angle of 37.69∘ was found on the SiO2+TiO2 spin-coated surface, and the maximum contact angle was 72.10∘ on the MgF2 dip-coated surface. This shows that the self-cleaning properties in SiO2+TiO2 spin-coated surfaces are maximum and minimum in MgF2 dip-coated surfaces. The angle found by the test shows that spin coating is a better technique than dip coating for hydrophilic surface coating. This was due to the more homogenous coating on the spin-coated sample surfaces. There was less accumulation of dust found on the coated surfaces compared to non-coated glass sample surfaces. [ABSTRACT FROM AUTHOR]

In this study, the spin coating process was used to develop perovskite solar cells in a two-step process. Thermal annealing of the perovskite solar cells was done from 90 to 120 °C, and the microstructure and solar cell properties of the perovskite were determined. The result shows that the thermal annealing temperature affects the degree of crystallisation of the perovskite layer. The optimal result was obtained at 120 °C, where the efficiency was 9.6%, fill factor = 0.45, Jsc = 12.51 mA/cm2, and Voc = 0.822 V. It has been established that combined-effect two-step spin coating and thermal annealing can be used to enhance the solar properties of lead-based perovskites. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) cells offer a promising method for producing green hydrogen through the splitting of water using solar energy. However, the cost‐effective synthesis of highly crystalline p‐type semiconductor materials for PEC cells remains a significant challenge for industrial applications. Herein, a CuInS2 photoelectrode is fabricated using a scalable and economical wet chemical spin‐coating technique. To enhance the crystallinity and photoelectrochemical activity of the photoelectrode, the grain size is precisely controlled by adjusting the atomic ratio, thickness, morphology, and Ag doping. Evaluating a novel growth mechanism of CuInS2 from Cu–In–O reveals that Ag doping significantly promotes grain growth. Consequently, the CuInS2 photocathode achieves one of the highest photoelectrochemical activities (−9.8 mA cm−2 at 0 VRHE) reported for CuInS2 photoelectrodes synthesized via wet chemical methods. Bias‐free water splitting is achieved using a CuInS2‐based photoelectrode in a photovoltaic–PEC cell configuration. These results highlight the potential of CuInS2, prepared through wet chemical methods, for cost‐effective photoelectrochemical water splitting. [ABSTRACT FROM AUTHOR]

The Europium (Eu(III))-doped Cu2ZnSnS4 (CZTS) thin films were prepared by spin coating method. Structural, morphological and elemental composition were analysed by X-ray Diffraction (XRD), Raman Spectroscopy and Scanning Electron Microscope with Energy-Dispersive X-ray analysis (SEM–EDX). Optoelectronic properties were analysed by UV–VIS-NIR Spectrophotometer and Van der Pauw Ecopia HMS-3000 Hall Measurement System. The XRD patterns verified the kesterite structure and Eu(III) doping was shown to increase crystallite sizes. High absorption was seen in the visible region of the UV–VIS-NIR spectra, and as the doping percentage was increased, the band gaps were dropping from 1.92 to 1.80 eV. The SEM images exhibited enhanced grain growth from several nano-meters to micrometers along with agglomeration of different sizes. The Hall measurements showed that the undoped CZTS and 1% Eu(III) doped CZTS as p-type semiconductors, suitable absorber layer of thin film solar cells, 2% and 3% Eu(III)-doped samples as n-type semiconductors. [ABSTRACT FROM AUTHOR]

Metal oxide thin‐film transistors (TFTs) offer remarkable opportunities for applications in emerging transparent and flexible microelectronics. Unfortunately, their performance is hindered by limitations associated with parasitic effects, such as parasitic electrode overlap capacitances and high contact resistance, which can severely limit their dynamic behavior. Here, an innovative method is reported to fabricate coplanar self‐aligned‐gate (SAG) indium‐gallium‐zinc‐oxide (IGZO) transistors with engineered source/drain contacts. The manufacturing process starts with the deposition and patterning of a gate electrode/dielectric stack and its functionalization with an organic self‐assembled monolayer (SAM) as the surface energy modifier. A second gold (Au) electrode is subsequently deposited over the gate electrode stack. The overlapping region between the two electrodes is removed via self‐delamination under mild sonication, forming perfectly aligned coplanar Au‐Gate‐Au electrodes. Device fabrication is completed with the spin coating of the IGZO precursor, followed by rapid photonic curing. Replacing the gold source/drain contact with bimetallic electrodes such as Au/In and Au/ITO enables a reduction in contact resistance and improves the transistor performance remarkably without increasing manufacturing complexity. The method is highly scalable, robust, and applicable to other semiconductor materials. [ABSTRACT FROM AUTHOR]

Transition metal-doped diluted semiconductor materials have attracted significant interest in spintronic applications. In order to investigate the structural, optical, electrochemical, and magnetic properties of these diluted magnetic semiconductors, transition metal-doped ZnO thin films were successfully produced at room temperature using a low-cost sol-gel spin coating technique with the same molar ratios. XRD analyses revealed that all samples adopted the crystal structure of ZnO. Optical measurements indicated high transparency in the visible region for all samples, while electrical measurements confirmed that all samples were n-type semiconductors. Finally, magnetic measurements showed that pure ZnO and Al- doped ZnO exhibited diamagnetic behavior, while Ni and Co doped ZnO displayed magnetic behavior. These results show that Co and Ni-doped ZnO films can be used as diluted magnetic semiconductor materials in spintronic applications. [ABSTRACT FROM AUTHOR]

Photoelectrochemical (PEC) photodetectors convert light into electrical signals via PEC processes, providing high sensitivity, positioning them as promising candidates for next-gen optoelectronic devices. Over the past few years, there has been a significant interest in the field of photodetection regarding 2D materials, owing to their advantageous properties. In this study, the PEC photodetection of hydrothermally synthesized MoS2–Se nanocomposites have been systematically tested. Structural analysis confirms the coexistence of MoS2 and Se phases in the synthesized nanocomposites with crystallite sizes in the nanoscale dimension. Optical studies indicate that MoS2–Se nanocomposites exhibit broadened absorption spectrum extending to UV region, unlike pure MoS2 which absorbs solely in the visible region. This enhances their sensitivity for wide-band photodetectors with a small bandgap (1.01–1.34 eV). Optoelectronic study revealed superior performance of MoS2–Se thin film PEC device with efficient photoresponse with a responsivity of 38.3 μA/W and fast response time of 0.12 s. The novelty of this research resides in the integration of these unique features in MoS2–Se nanocomposites for PEC photodetectors, explored for the first time. The innovative aspect of this study involves employing spin coating to deposit 2D MoS2–Se thin films, which enhances control over film thickness and uniformity, thereby resulting in improved responsivity and photocurrent. [ABSTRACT FROM AUTHOR]

Fluorine-Doped Tin Oxide (FTO) thin films were deposited on a glass substrate using the spin coating technique and then annealed in both open air and nitrogen environments at temperatures between 500°C and 600°C. This study examined how annealing temperature affects the structural and electrical properties of the films. X-ray diffraction (XRD) analysis showed that the films had a polycrystalline structure, predominantly with the (110) plane. As the annealing temperature is increased, the crystal size also increased, leading to lower dislocation density and higher electron mobility. The resistivity of the films decreased with higher annealing temperatures, reaching its lowest value at 600°C. These findings indicate that annealing temperature is crucial for optimizing the structural and electrical properties of FTO thin films made via spin coating. The optimal annealing conditions were found to be 600°C in open air, resulting in a resistivity of 2.47x10-3 Ω-cm, sheet resistance of 1.08x10-2 Ω/square, the largest grain size of 18.41 nm, and the lowest values for dislocation density (2.95x1015 lines/cm²) and micro-strain (1.97x10-3). [ABSTRACT FROM AUTHOR]

Currently, 2D nanomaterials-based resistive random access memory (RRAMs) are explored on account of their tunable material properties enabling fabrication of low power and flexible RRAM devices. In this work, hybrid MoS2–GO based active layer RRAM devices are investigated. A facile hydrothermal co-synthesis approach is used to obtain the hybrid materials and a cost-effective spin coating method adopted for the fabrication of Ag/MoS2–GO/ITO RRAM devices. The performance of the fabricated hybrid active layer RRAM device is analysed with respect to change in material properties of the synthesized hybrid material. The progressive addition of 0.5, 1.5, 2.5 and 4.5 weight % of GO to MoS2, results in a hybrid active layer with higher intermolecular interaction, in the case of Ag/MoS2–GO4.5/ITO RRAM device, resulting in a unipolar resistive switching RRAM behavior with low SET voltage of 1.37 V and high I on/ I off of 200 with multilevel resistance states. A space charge limited conduction mechanism is obtained during switching, which may be attributed to the trap states present due to functional groups of GO. The increased number of conduction pathways on account of both Ag+ ions and oxygen vacancies (Vo2+), participating in the formation of conducting filament, results in higher I on/ I off. This is the first report of unipolar Ag/MoS2–GO/ITO RRAM devices, which are particularly important in realizing high density crossbar memories for neuromorphic and in-memory computing as well as enabling flexible 2D nanomaterials-based memristor applications. [ABSTRACT FROM AUTHOR]

In the pursuit of high‐efficiency polythiophene (PT) organic solar cells (OSCs), a critical challenge is the reduction of nonradiative recombination. This study comprehensively explores polydithienylthiazolothiazole (PTTz)‐based PT terpolymers: PTTz‐Tz and PTTz‐TzT, in which it is demonstrate that molecular structure alterations greatly influence the aggregation kinetics and orientation of these polymers. Specifically, PTTz‐TzT achieves rapid ordering aggregation during spin coating, effectively suppressing excessive polymer aggregation and facilitating appropriate phase separation upon mixing with the acceptor. Meanwhile, PTTz‐TzT inherently adopts a face‐on orientation, resulting in more structured π–π stacking in the vertical direction after acceptor integration, compared to the intrinsic edge‐on orientation of PTTz‐Tz. These factors collectively contribute to lower Urbach energy and a substantial reduction of nonradiative recombination in PTTz‐TzT‐based OSCs, culminating in a high photovoltaic conversion efficiency (PCE) exceeding 16%. Furthermore, a prominent PCE of 19.11% is obtained by PTTz‐TzT via ternary blend strategy, which is among the highest values reported for the OSCs. This investigation underscores the significance of aggregation kinetics and orientation in PT‐based polymers, especially regarding Urbach energy and nonradiative recombination, and offers novel insights for designing high‐performance polythiophene donors. [ABSTRACT FROM AUTHOR]

An oxide-based thin film heterostructure was produced using the sol-gel method. A layered structure composed of the semiconductor oxides SnO 2 , ZnO and TiO 2 was achieved through spin coating technique. The obtained samples were characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FEG-SEM), energy dispersive X-ray spectroscopy (EDX), atomic force microscopy (AFM) and UV–Vis spectroscopy. The thin film heterostructure exhibits a homogeneous surface, free from defects, cracks or delamination. Nanometric grains and nanofibers conform the surface, and a uniform submicronic film thickness was achieved. High values of optical transmission (>83 %), and band gap values were estimated from their absorption spectra. The photocatalytic activity was determinated through the degradation of the methylene blue dye (MB). The assessment of the biocidal effect of the film against Escherichia coli and Staphylococcus aureus bacteria demonstrated significant bactericidal properties. [ABSTRACT FROM AUTHOR]

Multifunctional thin films are becoming extremely popular in many technological fields. An increase in their functionality can be achieved by the creation of nanocomposite structures. This study represents novel thin composite coatings with a horizontally oriented single-walled carbon nanotube (SWCNT) filler inside a silicon oxynitride (SiO x N y) matrix obtained by (i) low-temperature thermal curing or by (ii) UV radiation-induced curing. The SiO x N y /SWCNT composite structures were prepared by simple dry transfer of a SWCNT film into a perhydropolysilazane (PHPS) polymer matrix film deposited by the spin-coating technique followed by curing. The structural, morphological, and optical properties of the SiO x N y /SWCNT composite films were studied using HR-SEM/EDX, ATR-FTIR, and UV–Vis spectroscopy. It was found that SWCNT films were uniformly transferred into the PHPS matrix, maintaining their horizontally oriented close-packed structure, and avoiding the problem of agglomeration, thereby forming a laminate-type composite. SWCNTs had no effect on the curing process of the PHPS matrix. The SWCNT concentration remained relatively low, resulting in highly transparent composite films. An antireflection effect in the composite film relative to the transmission of the SWCNT film was observed. The results indicate that SiO x N y /SWCNT composites are attractive for applications as protective, antireflective optical coatings. [Display omitted] [ABSTRACT FROM AUTHOR]

The versatility of spin coating technology makes it a preferred method for producing the thin film layers used to manufacture products from solar panels and smartphones to sunglasses and CDs. However, the process requires a flat, rigid substrate to produce uniform films, which limits its use to planar devices. A novel multi-axis manipulator has been developed to extend the application of spin coating, enabling controlled thin film deposition onto curved surfaces. Various rotational schemes were studied to link the flow of a liquid film over a curved surface to forces induced by complex rotational dynamics. When the angular velocity exceeds a threshold, centrifugal force dominates the flow, pushing the fluid away from the instantaneous axis of rotation. This produces axisymmetric coating profiles when using consistent single or dual-axis rotation. Areas of near uniformity present around the spin axis poles for single-axis rotation and around the substrate's equator for dual-axis schemes. Sensitivities between the spherical substrate dynamics and the evolving fluid flow were investigated, exploring the parameters that promoted the production of uniform curved film layers for microfabrication processes. This enabled the evolution of the spin coating technique to effectively form curved polymer coatings with improved thickness control. The presented research outlines the capabilities of a multi-axis spin coating machine when used to coat spherical substrates. Therefore, enabling the use of fluid mechanics models to identify the optimal motion kinematics required to create uniform curved films. [ABSTRACT FROM AUTHOR]

Engineering new chalcogenide solids improves the desired functionality of the materials and may open the way for new applications. Here we discuss the preparation of As x S 100−x amorphous thin films modified with WS 3 by the sol–gel method. We show that the formation of homogeneous, transparent, and stable n-propylamine-based solutions by mixing 0.02M As x S 100−x and 0.02M (NH 4) 2 WS 4 solutions is feasible for the As content in the chalcogenide glass precursor x ≤ 25 at.%. Above this limit, rapid and massive precipitation occurs in the solutions. We further demonstrate the preparation of amorphous thin films along the pseudo-binary AsS 3 - WS 3 tie-line and provide information about the role of WS 3 on optical properties and the structure of tungsten-based chalcogenide thin films. Due to a significant etching contrast between annealed AsS 3 − WS 3 thin films at 70 and 240 ∘ C , we propose tungsten-based chalcogenide thin films as a suitable platform for application in wet-lithography. [Display omitted] • Homogeneous, transparent, and stable solutions by mixing As x S 100−x and (NH 4) 2 WS 4 solutions for x ≤ 25 at.%. • The WS 3 content increases the thermal stability of prepared thin films. • Optically transparent amorphous AsS 3 − WS 3 thin films up to a molar ratio of 1:3. • As WS 3 increases, the absorption edge is red-shifted. • The chemical resistance decreases to amine-based solutions with increasing WS 3 content. [ABSTRACT FROM AUTHOR]

Copper oxide thin films undoped and doped with silver (15 wt.%, 25 wt.%) were deposited by two different methods, namely sol gel dip coating and sol gel spin coating, on a glass substrate with a 0.2 M precursor concentration. The samples are characterized by X-ray diffraction, Fourier-transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray, UV-visible spectrophotometry, and the four-point, probe method. Structural, morphological, optical, and electrical properties of Ag-doped CuO are studied. According to the X-ray diffraction spectroscopy, all peaks confirm the formation of the tenorite phase with a monoclinic structure. The thin films were all polycryst.alline with directions along (200). According to scanning electron microscopy, the morphology of the films is almost smooth. A comparison is made between the two techniques of fabrication in terms of electric conductivity, morphology, energy gap, and average transmission in the visible domain. [ABSTRACT FROM AUTHOR]

Tin oxide (SnO2) thin films were deposited on glass substrates using a cost-effective spin coating method. The effect of solution molarity on their microstructural, optical, and electrical properties was investigated. For this purpose, solutions of tin chloride salt were prepared with various molarity in the range of 0.1M to 0.25M. The synthesized films structure and morphology were characterized by different techniques such as X-ray diffraction and scanning electron microscopy. The optical and electrical properties were studied by mean of UV-Vis spectroscopy and four probes conductivity measurement. The X-ray diffraction patterns of all samples revealed well-crystallized and pure SnO2 films with tetragonal rutile structure. The scanning electron microscopy images reveal a smooth and dense film pinholes free. The optical analyses show that the films exhibit an optical transparency that reaches up to 98% in the visible range and that the optical band gap decreases from 3.97 to 3.82 eV when the concentration increases from 0.1M to 0.25M. The films' electrical conductivity varies in the range from 76 to 100 (Ω cm)–1. The largest figure of merit of 9.8 × 10–3 was measured in the films prepared at low solution concentration. [ABSTRACT FROM AUTHOR]

The proper control of perovskite crystal morphology is a fundamental aspect of achieving efficient perovskite solar cells (PSCs) by ensuring better film coverage on an electron transport layer (ETL). In this study, three distinct approaches to depositing perovskite were thoroughly examined using different measurement techniques such as X-ray diffraction, photoluminescence spectra, UV-visible spectroscopy, and scanning electron microscopy. The impact of these perovskite deposition methods performed in an air-processed condition on the power conversion efficiency (PCE) of PSCs was thoroughly investigated. The results highlight that the infiltration of a mesoporous TiO2 ETL scaffold with perovskite solution yields much better coverage when employing sequential deposition processing, as opposed to single-step deposition processing. Moreover, the performance of perovskite-based photovoltaics is significantly improved to 6.8% by employing the two-step deposition dipping approach, which actively prevents the development of disorganized capping layers. This surpasses the 5.2% efficiency achieved through the one-step deposition method. Additionally, by optimizing the thickness of the mesoporous TiO2 film and using the spin coating method for the organic precursors in the process of perovskite formation, a significant enhancement in PCE is accomplished, surpassing 13.6%. Moreover, the best performing devices without encapsulation can retain 97% of the initial PCE over 40 days, under dark, 35% relative humidity, and room temperature. Hence, in this study the ambient air fabrication capability of the sequential deposition approach is demonstrated for the efficient and stable PSCs. [ABSTRACT FROM AUTHOR]

A LOx-based electrochemical biosensor for high-level lactate determination was developed. For the construction of the biosensor, chitosan and Nafion layers were integrated by using a spin coating procedure, leading to less porous surfaces in comparison with those recorded after a drop casting procedure. The analytical performance of the resulting biosensor for lactate determination was evaluated in batch and flow regime, displaying satisfactory results in both modes ranging from 0.5 to 20 mM concentration range for assessing the lactic acidosis. Finally, the lactate levels in raw serum samples were estimated using the biosensor developed and verified with a blood gas analyzer. Based on these results, the biosensor developed is promising for its use in healthcare environment, after its proper miniaturization. A pH probe based on common polyaniline-based electrochemical sensor was also developed to assist the biosensor for the lactic acidosis monitoring, leading to excellent results in stock solutions ranging from 6.0 to 8.0 mM and raw plasma samples. The results were confirmed by using two different approaches, blood gas analyzer and pH-meter. Consequently, the lactic acidosis monitoring could be achieved in continuous flow regime using both (bio)sensors. [ABSTRACT FROM AUTHOR]

Recently, much research has focused on the search for new mixed donor–acceptor layers for applications in organic electronics. Organic heterostructures with layers based on the generation 1 poly(propylene thiophenoimine) (G1PPT) dendrimer, N,N′-diisopropylnaphthalene diimide (MNDI), and a combination of the two were prepared and their electrical properties were investigated. Single layers of G1PPT and MNDI and a mixed layer (G1PPT:MNDI) were obtained via spin coating on quartz glass, silicon, and glass/ITO substrates, using chloroform as a solvent. The absorption mechanism was investigated, the degree of disorder was estimated, and the emission properties of the layers were highlighted using spectroscopic methods (UV–Vis transmission and photoluminescence). The effects of the concentration and surface topographical particularities on the properties of the layers were analyzed via atomic force microscopy. All of the heterostructures realized with ITO and Au electrodes showed good conduction, with currents of the order of mA. Additionally, the heterostructure with a mixed layer exhibited asymmetry in the current–voltage curve between forward and reverse polarization in the lower range of the applied voltages, which was more significant at increased concentrations and could be correlated with rectifier diode behavior. Consequently, the mixed-layer generation 1 poly(propylene thiophenoimine) dendrimer with N,N′-diisopropylnaphthalene diimide can be considered promising for electronic applications. [ABSTRACT FROM AUTHOR]

The facile spin coating fabrication of high‐dielectric‐constant (high‐k) multicomponent (Al,Ti,V,Zr,Hf)Ox films with an equivalent oxide thickness of ≈0.95 nm and the investigation of their thermal stability and dielectric and electrical properties of the resulting advanced metal–oxide–semiconductor (MOS)‐based electronic devices are reported in this study. Various heating conditions, including drying following spin coating, annealing after drying, and forming gas annealing, were investigated to optimize the quality of the films and reduce film defects. The favorable film‐based MOS devices exhibited robust capacitance–voltage (C–V) and current–voltage (I–V) characteristics with a remarkable k value of approximately 62 at 1 kHz. The thermal stability of the films was affirmed through a rapid thermal annealing treatment at 900°C for 5 s and observation of nondegraded C–V and I–V curves. The electrical performance of the resulting MOS field‐effect transistors (MOSFETs), including a threshold voltage of 0.4 V, an on/off ratio of 106, a saturated mobility of 40.1 cm2 V−1 s−1, and a subthreshold swing of 66.7 mV dec−1, was obtained. Moreover, hole‐ and electron‐trapping measurements through negative and positive gate bias stress instabilities, respectively, indicate the reliable performance of our MOSFETs. Our results imply that solution‐based processes are promising for fabricating fundamental semiconductor devices. [ABSTRACT FROM AUTHOR]

Calcium phosphate materials, particularly hydroxyapatite (HA), are extensively used in biomedical applications because of their prominence as primary inorganic constituents of human hard tissues. This study investigates the synthesis of HA coatings via spray pyrolysis using various precursors, including HA derived from bovine bone. The effects of pH on the formation and properties of HA coatings were systematically examined. Samples exposed to acidic conditions or left without pH adjustment led to the formation of HA, contrasting with the outcomes observed through dissolution methods. Different characterization techniques, such as scanning electron microscopy (SEM), transmission electron microscopy (TEM), and X‐ray diffraction (XRD), were employed to evaluate the quality and crystallinity of the coatings. Among the samples, those exhibiting superior crystallinity and nanostructured features, including bovine HA, were selected for further surface functionalization with the antibiotic enrofloxacin using spin coating. As expected, the antibiotic loading on each material's surface depended on the amount of HA deposited on the substrate. However, the desorption results indicated that, in all cases, desorption persisted beyond 38 h, implying that HA‐loaded matrices could be effective systems for controlled and prolonged drug release, which could be useful in dental or orthopedic implants for inhibiting the growth of bacterial biofilms. [ABSTRACT FROM AUTHOR]

Recombination of charge carriers is the major issue for the sustainable operation of dye-sensitized solar cells (DSSC). Generally, an external voltage bias is necessary to efficiently segregate the excitons and restrict recombination. A ferroelectric An organic ferroelectric DSSC has been fabricated, and the performance was examined by altering the thickness of the ferroelectric polyvinylidene fluoride (PVDF) thin film stratum. The PVDF was coated using the spin-coating method, and the TiO2 anode and nitrogen-doped reduced graphene nanosheet cathode layers were coated using the doctor blade method. An enhancement in Jsc and Voc has been noted by a decrease in PVDF film thickness. A maximum efficiency of 3.9%, along with a 70.9% fill factor, was achieved for the irradiation of 10 mW/cm2 for the DSSC made with an 80-nm-thick ferroelectric PVDF layer. Further, the performance has been tested by coating the TiO2 anode using spin coating. After evaluating the current–voltage characteristics with a single diode model, it was found that low series and high shunt resistances are responsible for the observed enhancement in Voc, leading to an overall increase in device efficiency. [ABSTRACT FROM AUTHOR]

Second-generation solar cells, commonly known as thin-film solar cells, have emerged as promising alternatives to traditional silicon-based first-generation photovoltaic cells. The superstrate configuration is the most widely used structure for constructing thin-film solar cells. Nevertheless, light reflection from the front cover glass surface significantly contributes to energy losses in thin-film solar cells. In this study, a ZnO anti-reflection (AR) coating was introduced using the spin coating technique on a glass/FTO/CdS/CdTe/Cu/Au substrate to improve the power conversion efficiency of the solar cell by reducing front-surface reflectance. The ZnO layer deposited at 3000 rpm in 15 s showed the minimum reflectance and higher transmittance over a wavelength range of 500–900 nm. Further, the thickness of the film under optimal conditions was 63.32 nm, which is compatible with the ideal theoretical AR coating thickness of 65 nm. Comparing the device performance of the CdS/CdTe solar cell with and without AR coating, all tested devices showed an average short-circuit current density improvement of 6.8% and overall enhancement in power conversion efficiency of 9.3%. [ABSTRACT FROM AUTHOR]

Flexible sensors are used widely in wearable devices, specifically flexible piezoresistive sensors, which are common and easy to manipulate. However, fabricating such sensors is expensive and complex, so proposed here is a simple fabrication approach involving a sensor containing microstructures replicated from a sandpaper template onto which polydimethylsiloxane containing a mixture of graphene and carbon nanotubes is spin coated. The surface morphologies of three versions of the sensor made using different grades of sandpaper are observed, and the corresponding pressure sensitivities and linearity and hysteresis characteristics are assessed and analyzed. The results show that the sensor made using 80-mesh sandpaper has the best sensing performance. Its sensitivity is 0.341 kPa−1 in the loading range of 0–1.6 kPa, it responds to small external loading of 100 Pa with a resistance change of 10%, its loading and unloading response times are 0.126 and 0.2 s, respectively, and its hysteresis characteristic is ∼7%, indicating that the sensor has high sensitivity, fast response, and good stability. Thus, the presented piezoresistive sensor is promising for practical applications in flexible wearable electronics. HIGHLIGHTS: • A piezoresistive flexible sensor is fabricated by replicating microstructures from sandpaper onto a PDMS-RGO-CNT composite. •The sensor exhibits sensing performance with high sensitivity, rapid response, and low hysteresis. •Larger microstructures replicated from sandpaper show better performance compared to smaller ones. [ABSTRACT FROM AUTHOR]

Aluminum (Al) and its alloys have been widely used in daily life, but the absence of antibacterial properties makes them potential vectors for bacterial transmission. In this study, an Ag-doped TiO2 coating was successfully prepared on the porous surface of etched Al foil using the sol-gel method. The results indicated that the porous layer allowed the gel to permeate through the holes, thereby forming an interface carrying these antibacterial agents with a thickness of about 10 μm. The Ag dopant promoted the transformation of titania from rutile to anatase during the calcination process, with the rutile being absent when the atomic ratio of Ag to Ti reached 0.10. Meanwhile, the doped Ag+ was thermally decomposed into metallic Ag0. As a result, doping Ag enhanced the photocatalytic efficacy of TiO2 coating. Moreover, the antibacterial rate of this coating against Escherichia coli and Staphylococcus aureus under dark conditions could reach more than 99%, and the corrosion resistance of the Al foil was also slightly improved by it.

In a thick-dielectric electroluminescent (TDEL) device, which is a variation of thin-film electroluminescent devices, one of the insulation layers is replaced by a thick-film dielectric layer. High brightness and reliability are the features of TDEL owing to a higher withstanding voltage of the thick-film dielectric layer. This paper presents a new type of TDEL with a bottom emission structure. The thick-film dielectric layer was manufactured by spin coating using an ink material, which is a mixture of BaTiO3 powder and a binder resin. The thicknesses of the phosphor and dielectric layers were minimized to reduce the operating voltage. A threshold voltage as low as 50 V and a maximum luminance of 1000 cd/m2 were obtained at 60 V. [ABSTRACT FROM AUTHOR]

Sm, Zr co-doped HfO 2 films were deposited on a p-type silicon wafer using a cost-effective spin coating method. The influence of Sm, Zr co-doping concentration variation on structural, compositional, morphological, and electrical properties was examined. The dominance of the orthorhombic phase (o-phase) in comparison to the monoclinic phase was noted to rise with the simultaneous increment of Sm doping concentration and decrement of Zr concentration. A decrease in oxygen vacancies was noted for all the Sm, Zr co-doped HfO 2 films from XPS results. Nonporous and uniform distribution of grains was observed from Field Emission Scanning Electron Microscope (FESEM) and Atomic Force Microscopy (AFM) studies. Electrical studies of MOS capacitors based on Sm, Zr co-doped HfO 2 films revealed a low leakage current. C-V studies exhibited an increment of dielectric constant and a decrement of interface trap densities. Further, to obtain insights into the microscopic features of Sm, Zr co-doped films, impedance and modulus studies have been performed. The obtained results imply the potential of tuning Sm, Zr co-doping concentrations in HfO 2 towards stabilization of the orthorhombic phase and to enhance the dielectric constant of the films. [ABSTRACT FROM AUTHOR]

QCM-based alcohol vapor sensors have been widely researched, and various materials have been deposited onto the sensor surface to serve as a functional layer. However, non-conductive polymers such as SBS as a functional layer for alcohol sensors are still minimally reported. In this study, the SBS was deposited on 1 side of the QCM using the spin coating technique. After deposition, the layer was annealed for 1 h. The annealing temperatures are 100, 150 and 200 °C. The concentrations of exposed alcohol vapor were 5, 10, 15, 20, 25, 50, 75 and 100 ppm. This study demonstrated that the SBS layer has the potential to be a functional layer of alcohol sensors. SBS 200 °C is an optimum functional layer for alcohol vapor sensors due to its high Δf and sensitivity. Meanwhile, SBS 100 °C has poor Δf and sensitivity. This is due to the morphology of 200 °C SBS, which consists of more valleys that perform as interaction sites for SBS and alcohol molecules. However, one of the limitations of SBS as a functional sensor layer for alcohol sensors is its low selectivity, which is a characteristic of rubbery polymers. [ABSTRACT FROM AUTHOR]

Electrochromism involves a change in colour of certain materials when a reversible voltage is applied externally. Tungsten oxide (WO3) has been endowed as one of the versatile electrochromic materials because of its several benefits, including high availability and affordable fabrication. Furthermore, it is appropriate to be produced as thin films or coatings, which is what makes it captivating for a variety of uses. In view of growing applicability of WO3, there is a strong need to improvise its electrochromic attributes. Different fabrication techniques have been explored to fabricate WO3 thin films since their significance is growing in the present. The choice of fabrication technique plays an important role in modifying the electrochromism. One of the economical and easy way of thin film fabrication is spin coating. It is seen in the literature that spin coating technique has not been given enough focus for the fabrication of WO3 films. In this regard we have presented a comprehensive review on the perspective of spin coating technique for the fabrication of WO3 thin films towards profound electrochromism. Through this mini review, it is possible to have a quick overview of the work available on WO3 fabrication by spin coating and hence to improvise its applicability in electrochromism. [ABSTRACT FROM AUTHOR]

Zirconia coating has a lot of promise when it comes to enhancing the optical performance and laser-induced damage threshold (LIDT) of the mirror in laser systems. In this work, a high LIDT ZrO2 coating was created using the sol-gel spin coating technique. The anhydrous ethanol solvent was substituted with alcohol ether solvent, and the spin coating technique was employed to achieve a macro homogeneous and flawless ZrO2 coating. Additionally, organic polymer polyethylene glycol (average Mn 200, PEG200) doping was used to achieve the uniform ZrO2 coating with LIDT. ZrO2-PEG composite coatings with consistent LIDT and exceptional optical properties were created. Alcohol ether solvents helped the sol produce a more homogeneous gel coating on the substrate, as demonstrated by the ZrO2 coating microscope pictures. The LIDT with a 0.5 wt.% PEG200 content was the most uniform. PEG200 organic molecules were able to alter the link state of the ZrO2 particles. The macroscopic mechanical characteristics of the coatings revealed that the hardness and elastic modulus of the ZrO2-PEG composite coating were mostly influenced by the PEG200 content. When the PEG200 content was 0.3 wt.%, the hardness and elastic modulus of the ZrO2-PEG composite coating were the lowest with the highest of the LIDT at 39.25 ± 3.13 J/cm2 (@ 1064 nm, 11 ns, 1 mm2). Highlights: Stable ZrO2 sol was prepared by sol-gel technology with Zirconium (IV) n-propoxide solution, Diethylene glycol (DEG), acetic acid (HAc), and water in ethanol solvent. ZrO2 coating was developed on the fused quartz substrates by a spin coating method, and the effect of solvents on the uniformity of use investigated. The macro defect-free and uniform ZrO2 coatings were successfully obtained by changing the ethanol solvent to alcohol ether solvents. PEG200 had improved the LIDT of ZrO2 coating to a certain extent while enhancing the uniformity of the spatial distribution of it. [ABSTRACT FROM AUTHOR]