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In this study, a hybrid organic‐inorganic field‐effect transistor (FET) is proposed with n‐type zinc‐tin oxide (ZTO) and p‐type dinaphtho[2,3‐b:2′,3′‐f] thieno[3,2‐b]thiophene (DNTT), presenting two applications: (1) random number generator (RNG) and (2) spiking neuron. Interface challenges lead to operational instabilities such as bias stress and hysteresis due to trap site formation from oxide surface hydroxyl groups. However, these trap sites are utilized to produce unstable noise for RNG. Also, the impact of an internal interlayer is explored to mitigate instability in the negative transconductance (NTC) effect. This interlayer enhances material compatibility, improving turn‐on voltage, on‐off current ratio, and reducing hysteresis in the FET. These improvements highlight and maximize the robustness of NTC characteristics. Utilizing this behavior, a spiking neuron is demonstrated that emulates neuronal spiking and generates neuronal spike signals. [ABSTRACT FROM AUTHOR]

Surface plasmon resonance‐based fiber optic sensors with Ag‐SnO2 and Ag‐ZnS bi‐layers are proposed experimentally and compared in detail in terms of sensitivity. Effect of SnO2 and ZnS layer thicknesses on the sensitivity is examined. Largest sensitivities are achieved by sensors with 40 nm Ag‐10 nm SnO2 layers and 40 nm Ag‐10 nm ZnS layers. Sensor with 40 nm Ag‐10 nm SnO2 layers is found to demonstrate better sensitivity than that with 40 nm Ag‐10 nm ZnS layers. [ABSTRACT FROM AUTHOR]

Ceramics based on tin oxide (SnO 2) and zinc oxide (ZnO) were sintered at temperatures up to 1400 °C. Except for the end members, all these ceramics are two- or three-phase composites containing spinel phase (Zn 2 SnO 4). Similar to pure SnO 2 ceramics, also the spinel-rich composite (50:50 mixture) does not exhibit densification after sintering at 1400 °C. Spinel Zn 2 SnO 4 is formed in all composites, with a major increase of spinel content at around 1000 °C. Young's modulus values, determined via impulse excitation, are between the exponential relation for convex pores and a benchmark relation for concave pores (or a percolation relation). The evolution of Young's modulus during sintering reveals significant differences between SnO 2 (weak increase above 1000 °C), ZnO (significant increase above 800 °C) and the composites (intermediate). Spinel formation is revealed during heating by a distinct peak (elastic anomaly) at around 1000 °C. [ABSTRACT FROM AUTHOR]

Technological advances have accelerated the pursuit of transparent conducting thin films (TCFs) with superior mechanical properties, durability, efficient optoelectrical performance and substrate compatibility as a pivotal focus in the realm of flexible transparent electronics. Against this background, this work investigates the fabrication of multilayer silver nanowire (AgNW) thin films reinforced by zinc tin oxide (ZTO) thin film encapsulation on polycarbonate substrates by a combination of sputtering and spin-coating techniques. An investigation of the influence of AgNW percolation networks on the optoelectrical properties of ZTO/AgNW/ZTO hybrid thin films was carried out. The impact of ZTO protective layers on the enhancement of electrical properties, adhesivity, flexibility and environmental stability of the multilayer TCF was elucidated. Additionally, to explore the compatibility of the fabricated TCF in integrated device and stealth applications, its electromagnetic interference shielding properties were investigated. The hybrid TCF showed 99.47% EMI shielding efficiency with an absorption-dominant EMI shielding effectiveness of 22.7 dB in the x-band region. [ABSTRACT FROM AUTHOR]

Recently, the trend in solar cell research has become highly competitive, with researchers striving to find the best material that strikes a balance between various factors, including fabrication speed, cost, material toxicity, abundance, and overall photovoltaic performance. Typically, cadmium sulfide serves as the buffer layer in CZTS solar cells, but this material is known for its high toxicity. On the other hand, zinc tin oxide (ZTO) has gained popularity in solar cell applications due to its transparency, conductivity, thermal stability, and non-toxic nature. Consequently, the idea of using ZTO as an alternative buffer layer in CZTS solar cells has emerged. In this study, we synthesized nanocomposite thin films of Zn(1−x)SnxO (x = 0.100, 0.133, 0.167, 0.200, and 0.233% w/w) using the sol–gel method and spin coating technique. Among the various concentrations tested, the thin film composed of Zn0.833Sn0.167O demonstrated the highest power conversion efficiency (PCE) of 0.54%. This outcome marked a successful result, indicating that this particular composition optimizes efficiency in our study. It is noteworthy that excessive tin doping did not lead to improved efficiency. However, it is important to acknowledge that the PCE in our experiment is relatively low compared to that of other researchers due to the use of ITO glass as the back contact, chosen for economic considerations. Furthermore, our fabrication method for ZTO thin films resulted in a bandgap energy (Eg) value of 0.78 eV. In summary, our findings suggest that ZTO has the potential to replace cadmium sulfide as the buffer layer in CZTS-based solar cells. These findings are expected to have a significant impact on promoting ZTO as the primary buffer material in CZTS solar cell technology. [ABSTRACT FROM AUTHOR]

Thin films of composite Zinc Tin Oxide (ZTO) are grown on glass substrates by thermal vapor evaporation. Thin films with different ratios of ZnO: SnO2= (90:10, 80:20, 70:30, 60:40 and 50:50) wt% were prepared and annealed at 500 °C for 2 h. The X-ray diffraction (XRD) patterns reveal that the ZTO films have become polycrystalline as we increase the percentage of tin oxide. The crystallinity of films also increases significantly. The field emission scanning electron microscopy (FESEM) results indicate that the percentage of tin oxide changes the film's morphology. UV visible spectroscopy of the films indicates that the band gap is reduced with the increased percentage of tin oxide in the mixture, and transmittance is also decreased at a higher percentage. The transmittance of the films ranges from 90 to 83 %, while the band gap falls within the range of 3.90 to 3.40 eV. These characteristics make the films well-suited for solar cell window layers. [ABSTRACT FROM AUTHOR]

High-performance photodetectors are crucial to developing cutting-edge technologies in many disciplines, such as medicine, optical communication, display and imaging, military, environmental monitoring, security checks, scientific research, and industrial process control. Field-effect phototransistors (FETs) using an amorphous oxide semiconductor, zinc–tin oxide (ZTO), show great potential as next-generation photodetectors. Regrettably, typical ZTO-based FETs have drawbacks preventing their widespread adoption in commercial applications, including reduced photosensitivity, slow reaction time, and insufficient mechanical flexibility. Here, ZnO nanowire (NW) growth on ZTO-based FETs for a superior photosensitive self-powered photodetector was studied for the first time. Initially, the ZTO-based photodetector was illuminated under 550 μW/cm2 ultraviolet (UV) intensities, which exhibit sensitivity (responsivity) of 7.33 (0.21 AW–1) and 1.34 (0.66 AW–1) under atmosphere and vacuum environments, respectively. The excess oxygen ions in the atmosphere significantly boost photosensitivity compared to that in a vacuum environment. Furthermore, ZTO/ZnO NWs-based FETs were illuminated under 106 μW/cm2 UV intensities, thus exhibiting excellent sensitivity (responsivity) of 8.67 × 104 (160.79 AW–1) under an atmosphere environment. Moreover, our device is a promising candidate for UV detection under weak UV illumination. Additionally, the superior charge carrier transport and mobility of ZnO NWs lower the recombination rate of photogenerated charge carriers and extend the lifespan of free charge carriers in photodetectors. Highly sensitive photodetectors based on ZTO/ZnO NW transistors are expected to have critical applications in various forefront domain fields, including bio-, flexible, wearable, transparent electronics and neuromorphic synaptic applications. [ABSTRACT FROM AUTHOR]

We demonstrate an artificially-intelligent cornea that can assume the functions of the native human cornea such as protection, tactile perception, and light refraction, and possesses sensory expansion and interactive functions. These functions are realized by an artificial corneal reflex arc that is constructed to implement mechanical and light information coding, information processing, and the regulation of transmitted light. Digitally-aligned, long and continuous zinc tin oxide (ZTO) semiconductor fabric patterns were fabricated as the active channels of the artificial synapse, which are non-toxic, heavy-metal-free, low-cost, and ensure superior comprehensive optical properties (transmittance >99.89%, haze <0.36%). Precisely-tuned crystal-phase structures of the ZTO fibers enabled reconfigurable synaptic plasticity, which is applicable to encrypted communication and associative learning. This work suggests new strategies for the tuning of synaptic plasticity and the design of visual neuroprosthetics, and has important implications for the development of neuromorphic electronics and for visual restoration. Existing artificial corneas can assume partial functions of the human cornea, but sense reconstruction remains a challenge. Qu et al. develop an artificially-intelligent cornea with tactile sensation that enables sensory expansion and interaction. [ABSTRACT FROM AUTHOR]

The demand for flexible indoor organic photovoltaic cells (OPVs) is growing dramatically due to their simple and practical use as a powering aid for various electronic gadgets connected to the Internet of Things. Due to the brittleness of inorganic material‐based transparent bottom electrodes and their incompatibility with flexible organic substrates, it is extremely difficult to limit the influence of mechanical stress on the stability of flexible OPV. In this regard, choosing a mechanically stable and highly conductive transparent conducting oxide (TCO) is crucial. Therefore, flexible OPVs are fabricated onto a flexible (polyimide) substrate coated with mechanically stable TCO indium zinc tin oxide (IZTO). Sheet resistance measurements and observations of scanning electron microscope images of IZTO film after 100 000 bending repetitions (bending radius: 5 mm) confirm the ultrahigh mechanical stability of the TCO. The sheet resistance of flexible IZTO electrode layers is increased by 9%, from 17.42 to 19.12 Ω sq−1. In addition, the impact of a large number of bending repetitions on film transmittance is minimal. The OPV shows ≈69% and ≈20% of its initial power conversion efficiency value after 100 000 bending repetitions for 1000 lx LED illumination and 1 sun conditions, respectively. [ABSTRACT FROM AUTHOR]

Herein, the fabrication and characterization of low‐resistance all‐oxide transparent vertical β‐Ga2O3 diodes using indium tin oxide (ITO) and aluminum‐doped zinc oxide (AZO) Schottky contacts are reported. It is shown that an ITO ohmic contact to n+‐β‐Ga2O3 substrate is formed after annealing in N2 at 800 °C. Both AZO‐ and ITO‐based Schottky diodes show well‐behaved current–voltage characteristics. Average Schottky barrier heights and ideality factors are 0.99 and 1.05 eV and 0.95 and 1.03 eV for AZO and ITO Schottky contacts, respectively. The on‐off current ratio is about 2×$\times$1010 and 1×$\times$1010 for AZO and ITO Schottky contact, respectively. Moreover, the on‐state resistance is about 6–7 and 4–5 mΩ cm2 for AZO and ITO Schottky contact, respectively, and is 20–35 times lower than for previously reported transparent β‐Ga2O3 Schottky diodes. [ABSTRACT FROM AUTHOR]

In this paper, In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) films with a single spinel phase are successfully grown at the low temperature of 300 °C through careful cation composition design and a catalytic chemical reaction. Thin‐film transistors (TFTs) with amorphous In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) channel layers have a reasonable mobility of 41.0 cm2 V−1 s−1 due to the synergic intercalation of In and Sn ions. In contrast, TFTs with polycrystalline spinel In0.22ZnδSn0.78−δO1.89−δ (δ = 0.55) channel layers, achieved through a metal‐induced crystallization at 300 °C, exhibit a remarkably high field‐effect mobility of ≈83.2 cm2 V−1 s−1 and excellent stability against external gate bias stress, which is attributed to the uniform formation of the highly ordered spinel phase. The relationships between cation composition, microstructure, and performance for the In2O3–ZnO–SnO2 ternary component system are investigated rigorously to attain in‐depth understanding of the roles of various crystalline phases, including spinel Zn2−ySn1−yIn2yO4 (y = 0.45), bixbyite In2−2xZnxInxO4 (x = 0.4), rutile SnO2, and a homologous compound of compound (ZnO)k(In2O3) (k = 5). This work concludes that the cubic spinel phase of Zn2−ySn1−yIn2yO4 (y = 0.45) film is a strong contender as a substitute for semiconducting polysilicon as a backplane channel ingredient for mobile active‐matrix organic light‐emitting diode displays. [ABSTRACT FROM AUTHOR]

Cu(In,Ga)Se2 (CIGSe) thin‐film solar cells are a commercial photovoltaic technology that provides sustainable power. Herein, the formation of Zn1−xSnxOy (ZTO) thin films is studied as Cd‐free buffer layer by chemical bath deposition (CBD) suitable for CIGSe solar cell devices. ZTO films are obtained by CBD onto soda lime glass, by modifying a reported procedure otherwise leading to columnar ZnO thin films. These ZTO films show a flatter morphology compared to the reference ZnO due to inhibition of the columnar growth. In addition, a nontrivial increase in the bandgap is observed by enhancing Sn concentration. When a concentration of 20% [Sn]/([Sn] + [Zn]) (where [Sn] and [Zn] are the molar concentrations of Sn and Zn, respectively) is employed in the chemical bath, the resulting buffer layer allows the CIGSe solar cell to achieve similar performance as with a CdS buffer layer (average efficiency of (11 ± 2)%), yielding a maximum efficiency of 10.4%, with an average of (9 ± 2)%. [ABSTRACT FROM AUTHOR]

The variation in crystallinity, morphology and phase of zinc tin hydroxide nanostructures are investigated after annealing at different (oxidizing, non-oxidizing and reducing) atmospheres. The zinc tin hydroxide nanostructures are prepared using hydrolysis assisted co-precipitation method. Annealing in oxidizing (oxygen and air) and non-oxidizing (nitrogen and argon) atmospheres do not have a significant effect on morphological and structural properties. However, the annealing in the reducing (ammonia) atmosphere converts the cubic nanostructures into nanorods and spherical particles. The zinc tin hydroxide forms three new phases (ZnON, SnO 2 and Sn) after annealing in reducing atmosphere. The formation of ZnON and SnO 2 phases are evident in Raman and XPS analysis. The reducing atmosphere (ammonia) changes the reaction kinetics leading to diffusion control crystal growth that could be responsible for such structural and morphological transformation. The bandgap is significantly changed after morphological and structural transformation with notable variation in photocurrent density, charge transfer resistance, and charge carrier concentration. [ABSTRACT FROM AUTHOR]

In recent years, much attention has been paid to pharmaceuticals as potential toxic bioactive substances in the worldwide environment. These compounds are continuously introduced into the surroundings in small concentrations, which certainly affects the quality of water, ecosystem, and the general health of living organisms. Photocatalysis is a promising technique for treating pharmaceutically active compounds as organic pollutants over traditional technologies. This study proposes the application of photocatalysts composed of zinc oxide (ZnO) and tin oxide (SnO2), synthesized using a solid-state method, for the photocatalytic degradation of two selected psychoactive drugs, amitriptyline (AMI) and alprazolam (ALP), under simulated solar and UV irradiation in an aqueous system. The newly synthesized photocatalysts were characterized using the following techniques: SEM/EDS, XRD, DLS, and UV/Vis spectroscopy. The obtained data confirmed the successful synthesis and the possible photocatalytic application of the new materials. Concerning the photocatalytic evaluation, the main results indicate that the highest removal efficiency of AMI and ALP was reached in the presence of ZnO/SnO2 synthesized in a molar ratio of 2:1 and calcined at 700 °C, under 1.0 mg/mL catalyst loading. Based on the reutilization findings, it can be concluded that the mentioned photocatalyst had not lost its efficiency after three successive runs for the photodegradation of ALP. Additionally, pure ZnO powders showed the highest activity after calcination at 500 °C, in the case of both examined pollutants. The experiments with tert-butanol, sodium fluoride, and ethylenediaminetetraacetic acid suggested that the relative contribution of various reactive species changed in the following order: positively charged holes > OH free • > OH ads • . [ABSTRACT FROM AUTHOR]

Nanomaterials based on tin (IV) oxide (SnO 2) and zinc oxide (ZnO) were investigated in the search for active, environmentally benign, and inexpensive materials for the crucial reaction of CO 2 cycloaddition to epoxides to afford cyclic carbonates. In particular, nanoparticles (NPs), nanorods (NRs), nanosheets (NSs) and microplates (µPLs) were prepared and used in combination with small amounts of TBAI (tetrabutylammonium iodide) as the nucleophile. Different from the general case of metal oxides, often requiring harsh reaction conditions, the most active compound in this study, SnO 2 -NPs, served as an active material for the cycloaddition of CO 2 to several terminal epoxides under atmospheric pressure at moderate temperatures (60–80 °C) and could also be employed for converting internal epoxides under harsher conditions. Importantly, SnO 2 -NPs could also be used in the presence of impure CO 2 feeds (20% methane in CO 2) resembling low calorific landfill gas and could be recycled and reused. Overall, SnO 2 -NPs represent a promising, readily available, and inexpensive metal oxide-based material to produce cyclic carbonates under atmospheric CO 2 pressure. • Nanosized oxides of zinc and tin were explored for the synthesis of cyclic carbonates. • SnO 2 -NPs and TBAI catalyze the coupling of CO 2 and epoxides at atmospheric pressure. • Impure CO 2 could be used as the feed gas and the SnO 2 -NPs could be recycled. [ABSTRACT FROM AUTHOR]

Solid-phase sintering was used to make ceramic from a mixture of ZnO, SnO2, and TiO2 nanopowders used as precipitation-strengthening and arc-quenching components in silver-based electrocontact materials. The phase formation and microstructure of the resulting material were studied by electron microscopy, energy-dispersive microanalysis, and x-ray phase analysis. It was found that a dispersed structure of size 0.5 – 1.0 μm forms from the Zn2TiO4 and ZnO phases at sintering temperature 1123 K, and the samples have quite high porosity. Solid-phase reactions in the ZnO/TiO2 system at Tsint = 1123 K effect the formation of two-phase ZnO/Zn2TiO4 ceramic with zinc and tin oxide phases in residual amounts. At sintering temperature 1443 K grain growth occurs, Zn2SnO4 becomes the predominant phase, and a certain amount of zinc and tin oxide phases remains. There is no manifestations of titanium-containing phases (presumably TiO2 and Zn2TiO4), probably because of their low content. [ABSTRACT FROM AUTHOR]

In this study, a low-sophistication low-cost spray pyrolysis system built by undergraduate students is used to grow aluminum-doped zinc oxide thin films (ZnO:Al). The pyrolysis system was able to grow polycrystalline ZnO:Al with a hexagonal wurtzite structure preferentially oriented on the c-axis, corresponding to a hexagonal wurtzite structure, and exceptional reproducibility. The ZnO:Al films were studied as transparent conductive oxides (TCOs). Our best ZnO:Al TCO are found to exhibit an 80% average transmittance in the visible range of the electromagnetic spectrum, a sheet resistance of 32 Ω/□, and an optical bandgap of 3.38 eV. After an extensive optical and nanostructural characterization, we determined that the TCOs used are only 4% less efficient than the best ZnO:Al TCOs reported in the literature. This latter, without neglecting that literature-ZnO:Al TCOs, have been grown by sophisticated deposition techniques such as magnetron sputtering. Consequently, we estimate that our ZnO:Al TCOs can be considered an authentic alternative to high-performance aluminum-doped zinc oxide or indium tin oxide TCOs grown through more sophisticated equipment. [ABSTRACT FROM AUTHOR]

A major problem in world health care is the development of antibiotic resistance in bacteria. In light of this, pure and calcium-doped zinc tin oxide (ZTO) nanoparticles, Zn2SnO4 (S1), Zn2Sn0.7Ca0.3O4 (S2), Zn2Sn0.5Ca0.5O4 (S3), and Zn2Sn0.3Ca0.7O4 (S4), were synthesized via simple and cost effective microwave assisted method. The doping effect on antibacterial activity was studied in detail. The XRD spectrum revealed that all the deposited samples exhibited a spinel cubic structure. A decrease in crystallite size, an increase in strain and dislocation density was observed with an increase in Ca concentration. FESEM images exhibited an irregular and non-homogeneous nature with crystalline morphology having a physical dimension of nm size. EDAX confirmed the purity of deposited samples. We used the agar well diffusion technique to study the antibacterial activity of Gram-positive and Gram-negative bacteria. The doping of the ZTO matrix with Ca ions increased its antibacterial performance by 99% against Klebsiella pneumoniae bacteria, and its effectiveness was enhanced with increasing Ca ion concentration inside the Zn2SnO4 nanoparticles. [ABSTRACT FROM AUTHOR]

The measurement of mobility and threshold voltage in thin‐film transistors (TFTs) in which the mobility is a function of gate voltage or carrier density is usually done inaccurately. Herein, accurate mobility calculations within the framework of the gradual channel approximation are described. Conventionally, the derivative of drain current with respect to gate voltage is often used to calculate mobilities in the linear region. This procedure often leads to errors when the mobility is not constant. Using a first‐order finite difference‐based calculations, it is shown how the correct field‐effect mobility can be extracted. The corrected mobility can be smaller than the conventionally calculated field‐effect mobility by up to a factor of 2. It is also shown that the corrected field‐effect mobility is identical to the average mobility. A threshold voltage that is independent of gate voltage value and suitable for disordered semiconductors is used for more accurate mobility calculations. The mobility and threshold voltage calculations are illustrated with experimental data from multiple TFTs with indium gallium zinc oxide, zinc tin oxide, and molybdenum disulfide channel layers. [ABSTRACT FROM AUTHOR]

Due to the significant growth of the market for numerous flexible electronic devices, demand for mechanically stable indium zinc tin oxide (IZTO) based flexible transparent electrodes has recently expanded substantially. So, we have attempted to increase the mechanical stability of an IZTO based flexible transparent electrode by forming an ultrathin interlayer of an organic semiconductor polystyrene sulfonate doped polyaniline (PANI:PSS). According to the results of the systematic investigation, the PANI:PSS treated IZTO film can preserve 97.50% of its initial average transmittance (AVT) value (83.07%) after 20,000 bending cycles, but the bare IZTO film can retain only 89.00% of its initial AVT value (86.40%) after the same treatment. Furthermore, the PANI:PSS treatment has benefited in the reduction of IZTO film sheet resistance from 17.38 to 16.91 Ω/sq. Scanning electron microscopy images have indicated that the presence of a PANI:PSS interlayer on the IZTO film prevents the formation of fractures on the inorganic IZTO layer when mechanical stress is applied. [ABSTRACT FROM AUTHOR]

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Using first-principles calculations, we investigate the hydrogen evolution reaction (HER) on the noble-metal-nanoparticle-coated zinc or zinc-tin oxide surfaces. Among the six catalytic structures, the adsorption free energy of Au/ZnO structure is closest to zero. The relative energy diagrams reveal that Volmer-Heyrovsky mechanism on the NP (oxide) reactive site dominants the HER process on NP/ZTO (Pt/ZnO and Au/ZnO) structures. However, comparing the adsorption free energy and primary energy barrier of the prefer path of each structure, the Pt/ZnO structure shows the best performance for the HER process. • The HER performance of NPs-coated oxide were studied by first principle calculation. • The NPs surface of Au/ZnO structure shows the lowest adsorption free energy. • Pt cluster is the preferred surface for hydrogen spillover according to Bader charge. • Volmer-Heyrovsky mechanism on NPs surface of Pt/ZnO has the best HER performance. [ABSTRACT FROM AUTHOR]

Zinc tin oxide (ZTO) thin-film transistors (TFTs) were fabricated using the co-sputtering method with Sn and zinc oxide (ZnO) as targets. The Sn-sputtering power was varied to optimize the device performance of the ZTO TFTs. The chemical states of Sn3d and O 1s at the surface of the ZTO films were analyzed by X-ray photoelectron spectroscopy to explain the effect of different Sn contents of the ZTO films on the device performance of the ZTO TFTs. The oxygen vacancy and the ratio of Sn4+ and Sn2+ were found to significantly effect on the device performance. When the ZTO film has the highest concentration of Sn4+ and lowest content of oxygen vacancy, the device achieves the optimal mobility of 15.67 cm2/Vs, and the on–off current ratio reaches 1.17 × 108. [ABSTRACT FROM AUTHOR]

We investigate the physico-chemical origins that determine the transistor characteristics and stabilities in sol-gel processed zinc tin oxide (ZTO) thin-film transistors (TFTs). ZTO solutions with Sn/(Sn+Zn) molar ratios from 0.3 to 0.6 were synthesized to demonstrate the underlying mechanism of the electrical characteristics and bias-induced instabilities. As the Sn/(Sn+Zn) ratio of ZTO is increased, the threshold voltage of the ZTO TFTs negatively shifts owing to the gradual increase in the ratio of oxygen vacancies. The ZTO TFTs with an Sn/(Sn+Zn) ratio of 0.4 exhibit highest saturation mobility of 1.56 cm2/Vs lowest subthreshold swing and hysteresis of 0.44 V/dec and 0.29 V, respectively, due to the desirable atomic states of ZTO thin film. Furthermore, these also exhibit outstanding positive bias stability due to the low trap density at the semiconductor-dielectric interface. On the other hand, the negative bias stress-induced instability gradually increases as the proportion of tin increases because the negative bias stress instability originates from the ionization of oxygen vacancies. These results will contribute to the optimization of the composition ratio in rare-metal-free oxide semiconductors for next-generation low-cost electronics. [ABSTRACT FROM AUTHOR]

Although semiconducting metal oxide sensors present reasonable sensitivity, an improved lower detection limit and/or selectivity would allow broadening real-time monitoring applications. This work reports the growth mechanism and gas sensing performance of zinc tin oxide-based structures synthesised via a microwave-assisted hydrothermal route. The synthesised materials were characterised by X-ray diffraction (XRD), Raman and Fourier-transform infrared (FTIR) spectroscopy, scanning and scanning transmission electron microscopy (SEM and STEM), X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray spectroscopy (EDS), and nitrogen adsorption/desorption experiments. Gas sensor measurements showed that ZnSnO 3 presents an outstanding lower detection limit to nitrogen dioxide (NO 2), in which a 10-fold increase in electrical resistance is expected in the presence of 1 ppb NO 2 at an operating temperature of 150 ˚C. Moreover, the Zn 2 SnO 4 /SnO 2 heterostructure exhibited superior selectivity to NO 2 relative to hydrogen (H 2) and carbon monoxide (CO), exhibiting a sensor response ∼1500 times higher for the oxidising gas. Hence, it is demonstrated that nanostructures' growth engineering can realise lower detection limits and ultra-selective high-performance gas sensor devices through a greater surface area and enhanced contact potential barriers. [Display omitted] • Crystals with unique morphology were grown. • ZnSnO 3 nanostructures should present sub-ppb NO 2 detection. • Zn 2 SnO 4 /SnO 2 had a ∼3000 resistance surge under 100 ppm NO 2 at 150 °C. • Zn 2 SnO 4 /SnO 2 has a ∼1500 selectivity for NO 2. • Crystals growth and gas sensing mechanisms were detailed. [ABSTRACT FROM AUTHOR]

In this study, we fabricate and investigate a novel formaldehyde (HCHO) gas sensor, which utilizes an indium tin zinc oxide (ITZO) thin film, modified with gold nanoparticles (Au NPs), on a sapphire (Al 2 O 3) substrate. Intrinsic material properties are studied using various techniques including high-resolution scanning electron microscopy (HRSEM), energy dispersive X-ray spectroscopy (EDS), atomic force microscopy (AFM), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS). Experimental results demonstrate that, when exposed to a 20 ppm HCHO/air gas, the developed Au NP/ITZO sensor demonstrates superior sensing properties incorporating a high sensing response (S R) of 47.5, coupled with a response time of 234 s and a recovery time of 108 s at 250.°C. Additionally, a limited detectable level of 40 ppb HCHO/air (S R =1.05) is achieved at 250°C. Moreover, the studied sensor exhibits promised repetitivity, selectivity, and long-term durability over a period of 91 days when exposed to HCHO gas. • A new Au NP/ ITZO based chemiresistive-type sensor was fabricated and well studied. • The Au NP/ ITZO sensor exhibited good sensing performance and a wide detecting range on HCHO gas content. • The studied Au NP/ ITZO sensor showed good selectivity toward HCHO gas. • The Au NP/ ITZO sensor exhibited stability for long-term test. [ABSTRACT FROM AUTHOR]

Combining two electrochemically active elements into anode materials has emerged as a promising strategy for practical application in the next-generation sodium-ion batteries (SIBs). Herein, a mixed-phase coexistence of ZnSnO 3 and Zn 2 SnO 4 is successfully modulated by controlling the amount of cetyltrimethylammonium bromide (CTAB) via additive-assisted hydrothermal synthesis. The structural characterizations exhibit that the higher the concentration of CTAB added to the precursor solution, the higher the phase fraction of ZnSnO 3. The effect of incorporating CTAB additive on the interfacial synergy between the ZnSnO 3 and Zn 2 SnO 4 phases is also revealed by x-ray photoelectron spectroscopy. When using the mixed-phase materials as an anode in SIBs, the optimal addition of CTAB (ZTO500) demonstrates an excellent specific discharge capacity of ∼277.7 mAh g−1 with an 88 % retention after cycling 100 times at 50 mA g−1. Electrochemical characterizations show that by modulating the mixed-phase of ZnSnO 3 and Zn 2 SnO 4 , a superior charge transfer and conductivity across the anode are obtained, which also causes the combination of diffusion- and surface capacitive-controlled charge storage. Modulated mixed-phase engineering would provide a promising approach for effectively designing proper anodes in SIBs. [Display omitted] • A mixed-phase ZTO anode was designed by an additive-assisted hydrothermal route. • By controlling the amount of CTAB, the mixed-phase of ZnSnO 3 and Zn 2 SnO 4 was modulated. • The optimal anode showed a good capacity of 277.7 mAh g−1 and 88 % retention after cycling. • The optimal mixed-phase modifies the charge transfer and Na-ion diffusion kinetics. [ABSTRACT FROM AUTHOR]

In this study, ZnO, SnO2 and their composite (ZnO-SnO2) were synthesized by green route using aqueous extract of Solanum macrocarpon fruit and were used for the photo-reduction of hexavalent chromium. The synthetic route involved a two-step procedure, induced by temperature via calcination at 350 and 600 °C. The composite was prepared by the treatment of a mixture of the precursor compounds to a temperature up to 800 °C, and the extension of the temperature to 1000 °C, resulted in the emergence of ZnO-SnO2-Zn2SnO4 (ZTO). The nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV–vis spectroscopy. The XRD studies of the binary oxides confirmed a hexagonal wurtzite structure for the ZnO and a tetragonal phase SnO2, without any change in the diffraction patterns or supplementary diffraction peaks. The morphology of the nanoparticles indicated fairly spherical shapes for the ZnO, that tend to agglomerate with increase in temperature. The SnO2 showed rectangular shapes at both temperatures of reaction, while the ZnO-SnO2 composite showed the presence of both morphologies of the component binary oxides. In the photo-enhanced degradation study, under ultra-violet light, the effect of pH (2–8), concentration of chromium(VI) (2 – 8 ppm), and photocatalyst dosage (25 - 150 mg/L) on the reduction of Cr(VI) to Cr(III) were investigated. The reduction showed higher efficiency in acidic environment than in the alkaline environment, and also with increase in photocatalyst dosage. The composite exhibited the highest photoreduction efficiency, above 90%, at the optimum condition of pH 2, 150 mg/L photocatalyst, 2 ppm chromium solution after 90 min. These low-cost and nontoxic metal oxide and their green synthesized composite have great potentials for Cr(VI) pollution clean-up from waste water.

We focused on the importance of solvent evaporation governed by the temperature of the pre-annealing stage (TS) in solution-processed zinc tin oxide (ZTO) thin-film transistors (TFTs). We controlled TS based on the boiling point (BP) of the solvent used. When TS reaches the BP, the field effect mobility is found to be about 1.03 cm2/V s, which is 10 times larger than the TS < Bp case (0.13 cm2/V s). The reason is presumed to be that residual organic defects are effectively removed as TS increases. In addition, when Ts is beyond Bp, the mobility is rather decreased due to structural defects such as pores and pinholes. Based on our results, it is noted that TS plays a significant role in the enhancement of electrical performance and stability of solution-processed ZTO TFTs. [ABSTRACT FROM AUTHOR]

Real-time interpretation and modification of information can impart revolutionary advancements in the evolution of the internet of things. Synaptic transistors belong to a class of devices that mimic a biological synapse's fundamental characteristic functions. Moreover, the adaptive nature makes synaptic transistors the fundamental architectural element towards realizing the artificial brain. An imidazolium-based ionic liquid (IL)-gated zinc tin oxide (ZTO) synaptic transistor on a rigid substrate has been demonstrated here. The ZTO/IL interface was studied using electrochemical impedance spectroscopy, and it was observed that an electrical double-layer capacitance was formed below 1 kHz. Voltage dependent capacitance measurement shows a reasonably stable capacitance in the operating voltage of the synaptic transistor. The estimated capacitance was 0.58 µF at 20 Hz, resulting in high saturation mobility of 8.73 cm2 V−1 s−1 for the fabricated device. The transistor successfully mimics the fundamental biological synaptic functions such as short-term plasticity, long-term plasticity, and paired pulse facilitation. These devices consume very little power of the order of a few nJ/spike. Short-term plasticity is associated with the ion migration dynamics in IL and the IL gate bias induced conductivity change in ZTO channel layer is responsible for long-term plasticity. Device trained with 60 training pulses obtained a synaptic weight change of 768%. [ABSTRACT FROM AUTHOR]

High-performance tandem quantum-dot light-emitting diodes (QLEDs) are needed for practical next-generation displays. This study designed a high-performance interconnecting layer (ICL) that combines QLED units into tandem QLEDs and demonstrated its effectiveness. The ICLs were designed for charge generation, for interconnecting QLEDs, and for protecting the underlayers from damage during upper-layer fabrication. Using the ICLs with a first layer of thermally evaporated WO3 and a second layer of sputtered SnO2 or zinc tin oxide, the required roles of the ICL were fulfilled. The current efficiencies of tandem QLEDs using a double-layer ICL were about triple those of a single QLED, an improvement from 26 cd/A for a single QLED to 82 cd/A for a tandem QLED connecting two QLED units. This current efficiency was much higher than previously reported values for tandem QLEDs connecting QLED units with CdSe/ZnS green quantum dots and ZnO electron-transport layers. The method presented here will contribute to the practical application of QLEDs for large TVs and light-illumination devices. [ABSTRACT FROM AUTHOR]

A photodetector capable of detecting light illuminations ranging from ultraviolet (UV) to visible light spectrum using earth-abundant and environmentally friendly Cu-doped zinc tin oxide (Cu-doped ZTO) thin films is reported. Trilayer photodetector devices comprising P+-Si/10 at.% Cu-doped-ZTO-thin-film/indium-tin-oxide were successfully fabricated using radio-frequency (RF) magnetron sputtering. Optical and photoconductive characteristics of trilayer photodetector devices were investigated. The devices were found to exhibit superior photodetection capabilities, including high sensitivities of 1147 and 758, under 630-nm and 352-nm light illumination, respectively, and corresponding fast photoresponse times with a rise-time/fall-time of 8.9 ms/8.0 ms and 8.8 ms/8.0 ms. The induced mid-gap states from the Cu-dopant contributed extensively to the photoresponse through stable optical transitions. Air-annealing the Cu-ZTO thin films at 600°C effectively reduced the dark current, enabling Cu-ZTO thin films suitable for UV–visible light, wide spectral photodetector applications. [ABSTRACT FROM AUTHOR]

Thin‐film transistors (TFTs) based on ternary or quaternary metal oxides possess features that are advantageous for the commercialization of large‐area and flexible displays. These features include high mobility, high current on–off ratio, and uniformity over large areas. However, the manufacture of TFTs mainly uses costly sputtering equipment with low throughput. Here, it is demonstrated that cation exchange is a novel, solution‐based route for obtaining high‐quality ternary metal oxide films from binary metal oxide films. Specifically, some Zn ions in the parent ZnO film are replaced with In or Sn ions in a solution at room temperature, while preserving the ionic framework of the parent ZnO lattice to some degree. Consequently, annealing the resulting cation‐exchanged film at 250 °C yields an In‐ or a Sn‐doped ZnO film, in which In or Sn acts as a substitutional donor, with its electrical properties superior to those of the parent ZnO film. With the use of these In‐ and Sn‐doped ZnO films as channel layers, TFTs exhibit field‐effect mobilities of 10.3 and 7.1 cm2 V−1 s−1 and turn‐on voltages of −3.9 and −1.2 V, respectively, with current on–off ratios exceeding 108. [ABSTRACT FROM AUTHOR]

Piezoelectric/ferroelectric zinc tin oxide (ZnSnO3) nanocubes (NCs) are synthesized via a hydrothermal synthesis process. Piezoelectric materials exhibit a superior dielectric property, strong electric dipole moment, and higher piezoelectric coefficient, which results in an improved electrical output of the nanogenerator. The synthesized ZnSnO3 NCs are embedded in triboelectric polydimethylsiloxane (PDMS) polymer to employ the synergistic effect of ZnSnO3/PDMS composite polymer matrix (CPM), which creates a hybrid nanogenerator (HNG). The proposed HNG reveals a high electrical performance due to the improved dielectric constant as well as the synergistic effect of piezoelectricity and triboelectricity. Besides, a conductive filler material such as reduced graphene oxide (rGO) is synthesized using a modified Hummer's method and is further utilized to prepare an rGO‐ZnSnO3/PDMS CPM for improving the electrical output performance of the HNG. Furthermore, the ZnSnO3 NCs and rGO‐ZnSnO3 with different amounts are embedded into PDMS polymeric film to optimize the electrical performance of the HNG. The durability test of the proposed HNG device along with the robustness is investigated. Finally, the proposed HNG device is employed to harvest mechanical movements from daily life human activities to power various portable electronics. [ABSTRACT FROM AUTHOR]

The contamination of water resources by pollutants resulting from human activities represents a major concern nowadays. One promising alternative to solve this problem is the photocatalytic process, which has demonstrated very promising and efficient results. Oxide nanostructures are interesting alternatives for these applications since they present wide band gaps and high surface areas. Among the photocatalytic oxide nanostructures, zinc tin oxide (ZTO) presents itself as an eco-friendly alternative since its composition includes abundant and non-toxic zinc and tin, instead of critical elements. Moreover, ZTO nanostructures have a multiplicity of structures and morphologies possible to be obtained through low-cost solution-based syntheses. In this context, the current work presents an optimization of ZTO nanostructures (polyhedrons, nanoplates, and nanoparticles) obtained by microwave irradiation-assisted hydrothermal synthesis, toward photocatalytic applications. The nanostructures' photocatalytic activity in the degradation of rhodamine B under both ultraviolet (UV) irradiation and natural sunlight was evaluated. Among the various morphologies, ZTO nanoparticles revealed the best performance, with degradation > 90% being achieved in 60 min under UV irradiation and in 90 min under natural sunlight. The eco-friendly production process and the demonstrated ability of these nanostructures to be used in various water decontamination processes reinforces their sustainability and the role they can play in a circular economy. [ABSTRACT FROM AUTHOR]

In this article, we present a novel configuration of tin di-selenide (SnSe2) and zinc oxide (ZnO) based surface plasmon resonance (SPR) biosensor for DNA hybridization, urine abnormality, and anemia sensing. The configuration involves the stacked structure of prism (SF-10)/gold (Au)/ZnO/SnSe2/PBS. The performance parameters such as sensitivity (S), detection accuracy (DA), and figure of merit (FoM) are investigated at a fixed wavelength of 633 nm. Also, for SnSe2 the condition of zero chemical potential at room temperature was maintained. The obtained S, DA, and FoM are 153.3182 deg/RIU, 0.604 deg− 1and 9.15RIU− 1, respectively. [ABSTRACT FROM AUTHOR]

Great challenges remain concerning the cost-effective manufacture of high performance flexible transparent conductive thin films (TCFs). Here, we report flexible TCFs using Cu-embedded zinc tin oxide (ZTO) multilayer structures that are prepared on polyethylene terephthalate (PET) substrates at room temperature. The effects of Cu embedded layer thickness on conductivity and transparency are studied, and a new conduction mechanism is proposed to describe the conduction before and after the critical thickness. At the optimal condition, the films exhibit excellent performance in terms of optical and electrical characteristics, a largest figure of merit value is obtained as 173.2, while the sheet resistance is 9.92 Ω/sq. at an adequate transmittance of 81.2%. The resistance does not show great change after 1000 bending cycles, indicating good flexibility. Meanwhile, the resistance remains nearly constant after 100 tape tests, suggesting a good adhesion to the PET substrate. Moreover, the multilayer thin film exhibits good stability to resist humid and/or hot environments. The improvement of adhesion and stability of multilayer films can be attributed to the effective covering of ZTO on the Cu and disordered molecule arrangement of ZTO layers. In addition, the successful implementation of the multilayer films into a flexible transparent film heater is demonstrated, verifying the applicability. [ABSTRACT FROM AUTHOR]

This article presents the optimization of Zinc Tin Oxide/Silver/Zinc Tin Oxide (ZTO/Ag/ZTO) multilayers to implement them in thin film solar cells as transparent electrodes. To achieve improvements on the performance of these transparent multilayers, effect of Ag and ZTO thicknesses, and position of Ag layer within the multilayer were investigated. Electrical and optical characterization of these multilayers revealed that reduced sheet resistance and improved optical transmittance can be acquired for solar cells by the optimization of thin film thicknesses and position of the Ag within the multilayer. The improvement of the electrical and optical behavior of the ZTO/Ag/ZTO structures enabled figure of merit (FoM) values up to 69.69 × 10–3 Ω−1. The performance of our multilayer electrodes was also compared with ITO and AZO electrodes. The obtained results suggest that fabricated multilayer electrodes can be a good choice for thin film solar cells. [ABSTRACT FROM AUTHOR]

With the continuous advancement of high-tech industries, how to properly handle pollutants has become urgent. Photocatalysis is a solution that may effectively degrade pollutants into harmless molecules. In this study, we synthesized single crystalline Zn2SnO4 (ZTO) nanowires through chemical vapor deposition and selective etching. The chemical bath redox method was used to modify the ZTO nanowires with Ag nanoparticles to explore the photocatalytic properties of the nanoheterostructures. The combination of the materials here is rare. Optical measurements by photoluminescence (PL) and UV–Vis show that the PL spectrum of ZTO nanowires was mainly in the visible light region and attributed to oxygen vacancies. The luminescence intensity of the nanowires was significantly reduced after modification, demonstrating that the heterojunction could effectively reduce the electron-hole pair recombination. The reduction increased with the increase in Ag decoration. The conversion from the UV–Vis absorption spectrum to the Tauc Plot shows that the band gap of the nanowire was 4.05 eV. With 10 ppm methylene blue (MB) as the degradation solution, ZTO nanowires exhibit excellent photodegradation efficiency. Reusability and stability in photodegradation of the nanowires were demonstrated. Photocatalytic efficiency increases with the number of Ag nanoparticles. The main reaction mechanism was confirmed by photocatalytic inhibitors. This study enriches our understanding of ZTO-based nanostructures and facilitates their applications in water splitting, sewage treatment and air purification. [ABSTRACT FROM AUTHOR]

In this work, a novel flexible electrochemical sensor was successfully developed for the simultaneous determination of p-aminophenol and acetaminophen. The sensor is composed of a methanesulfonic acid-treated poly(3,4-ethylenedioxythiophene)/poly(styrenesulfonic acid) film on a poly(ethylene terephthalate) substrate, which has been modified using a zinc oxide-doped tin oxide heterojunction applied through drop-coating (C-ZnO/SnO 2 -PEDOT/PET). The oxygen vacancies resulting from zinc oxide-doped tin oxide heterojunctions within highly conductive metal oxide nanomaterials enhance mass transfer and synergize seamlessly with methanesulfonic acid-treated electrically conductive dielectric PEDOT/PET films, leading to a substantial improvement in electrochemical activity. Under the optimal conditions, a wider linear range and lower detection limits were shown for p-aminophenol (2–511 μM, LOD=0.437 μM) and acetaminophen (2–591 μM, LOD=0.562 μM). In addition, the sensors demonstrated high accuracy in detecting p-aminophenol and acetaminophen in real samples, with recoveries of 99.36 %-99.60 % and 97.56 %-99.80 %, respectively. Furthermore, the flexible sensors maintained a superior electrochemical response when detecting p-aminophenol and acetaminophen at different bending angles, with relative standard deviations of 0.62 % and 1.68 %, respectively. These findings suggest potential applications for the development of wearable sensors in the future. [Display omitted] A flexible ZnO/SnO 2 -modified PET plastic electrode is successfully fabricated. The ZnO/SnO 2 -PEDOT/PET can achieve simultaneous determination of PAP and APAP. The flexible sensor shows the excellent sensing performances for toxic pollutants. The sensor shows an excellent reproductivity and anti-interference ability. The sensor can maintain a stable electrochemical response under different bending. [ABSTRACT FROM AUTHOR]

Amorphous ZnO-SnO2 (a-ZTO) films were deposited on quartz substrates at working pressures of 5≤PW≤12 mTorr using radio frequency sputtering. PW affected the occurrence of oxygen deficiencies in the films. X-ray photoemission spectroscopy, near edge X-ray absorption fine structure (NEXAFS), and ultraviolet photoelectron spectroscopy-based spectroscopy analyses showed that oxygen vacancies (OVs) influence the evolution of the optical and electrical properties of a- ZTO films. NEXAFS reflects the onset of OVs. Low PW contributes to the evolution of a chemical structure with numerous OVs. This result can be applied to improve the electro-optical properties of a-ZTO films. As PW decreased, the carrier concentration increased, carrier mobility increased, and film resistivity decreased. Average optical transmittance in the visible region was>90%, and increased as PW decreased. [ABSTRACT FROM AUTHOR]

Using density-functional-theory calculations combined with hybrid functional, we investigate the band gaps and built-in electric fields of ZnSnN2/ZnO (001) short-period superlattices. The band gap of ZnSnN2/ZnO (001) superlattice can be tuned from 1.9 eV to 0 eV by varying the thickness of both the ZnSnN2 and ZnO regions. Compared to the III-nitride superlattices, stronger built-in electric fields, induced by the polarizations, form inside the ZnSnN2/ZnO superlattices. The lowest electron and uppermost hole states are mainly localized at the two opposite interfaces of the superlattice, but the tails of the lowest electron states extend over several atomic layers. Based on the electrostatic argument, we demonstrate that variations of the band gap are approximately described by a geometric factor. The influence of the in-plane strain is also discussed. The results will be valuable in the design of ZnSnN2/ZnO heterostructures for electronics and optoelectronics applications. [ABSTRACT FROM AUTHOR]

Biodiesel belongs to renewable energy and is a potential substitute for petrochemical diesel. In this study, ZnO/SnO 2 @halloysite heterojunction photocatalyst was prepared by loading semiconductor zinc oxide and tin dioxide on layered kaolin by the improved wet calcination method, which was used to photocatalytic the transesterification of castor oil and ethanol to produce biodiesel. TG-DTG, BET, XRD, UV–vis and SEM-EDS were used to characterize the composition, specific surface area, light absorption characteristics and photocatalytic performance of the samples. The reaction conditions were optimized by the Taguchi method. The optimum reaction conditions were as follows: catalyst dosage 4 wt%, molar ratio of ethanol to oil 12:1, reaction temperature 75 °C. After 2 h, the yield of biodiesel was 96.75 %. In the study of catalyst reusability, the yield of biodiesel is still above 85 % after being reused for 5 times. The kinetics of photocatalytic transesterification was studied, and the results accorded with quasi-first-order kinetics. The activation energy was 75.02 kJ/mol. Lastly, an eight-step reaction mechanism of photocatalytic transesterification was proposed. The prepared castor oil biodiesel can be prepared into B20 biodiesel through additives or mixing to meet ASTM D6751 and EN 14214 standards. [Display omitted] • Biodiesel was prepared from castor oil via photocatalytic transesterification. • ZnO/SnO 2 @halloysite heterojunction photocatalyst was created. • The yield of biodiesel optimized by the Taguchi method was 96.75 %. • After the catalyst was recycled 5 times, the yield of biodiesel was still above 85 %. [ABSTRACT FROM AUTHOR]

It is an inevitable trend to use artificial neural networks based on neurons and synapses to deal with the bottleneck of von Neumann architectures, and memristor is one of the most potential artificial synapses. Here, Zinc oxide doped tin (ZTO), as a resistive material of memristor with a planar structure of Cu/ZTO/FTO, was prepared using sol-gel and spin-coating methods. Such devices exhibit stable resistive transition within scanning voltage 4 V. In particular, the device shows adjustable synaptic plasticity simulations, including the alternation between habituation and sensitization, which can be regulated by amplitude, rest time of stimulus pulse and the number of positive and negative pulse. Such remarkable plasticity performance of memristor based on ZTO might have promising applications for artificial synapse devices. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of a novel electrode comprising of Ni-doped ZnO on a fluorine-doped tin oxide (FTO) glass was successful via a radio-frequency (RF) sputtering method. • The maximum removal of Remdesivir by synthesized photo-electrode was about 92% and total organic carbon (TOC), 74.1% was removed. • According to kinetic studies, pseudo-first-order model selected the best model. • The degradation pathway of Remdesivir was proposed. • Reusability investigations indicated well regenerability of Nickel doped-Zn/ FTO electrode. Currently, there has been increasing interest in developing active photocatalysts for the treatment of wastewaters. In this study, Nickel (Ni)-doped Zinc oxide on a fluorine tin oxide (ZnO/FTO) was synthesized and utilized as an electrocatalyst for efficient degradation and mineralization of remdesivir (REMD). Ni-ZnO/FTO electrode was characterized using XRD, SEM, EDX, LSV, and DRS analyses. The influence of operational parameters on the degradation efficiency procedure was explored in a batch photo-reactor and their optimum values were selected. At optimized conditions (e.g. initial REMD concentration = 1 mg/L, electrolyte concentration = 0.1 g/L, current intensity = 0.03 A, and pH = 7), within 2 h under UV-A, the removal efficiency of initial REMD concentration was 92 %, whereas TOC and COD removal efficiency were found as 80.1 % and 69.5 %, respectively. The assessment of the degradation rate within 2 h indicates that REMD degradation obeyed first order kinetic model. Additionally, in the comparison of degradation and mineralization efficiency of electrolysis, photolysis and photocatalytic and photoelectrocatalysis (PECP) processes for REMD removal, PECP gave the highest efficiency. The toxicity evaluations showed that the toxicity of solutions treated by the proposed PEC process significantly decreased in comparison with untreated controls. Based on reusability investigations, Ni-ZnO/FTO can be reused for at least five repetitive times with suitable efficiency. Moreover, by taking into account all results, it was concluded that the affordability, high potentiality, and well regenerability of Ni-ZnO/FTO make it an attractive electrocatalyst in terms of drug-containing wastewater treatment. [ABSTRACT FROM AUTHOR]

[Display omitted] • Sputtered flexible ZTO/Ag/ZTO thin film was deposited on polycarbonate substrates. • High average transmittance of 91.2 % and low R S of 18.6 Ω/□ was achieved. • Stable opto-electrical performance under various test conditions. • Absorption dominant EMI shielding of 21.76 dB was attained in the x-band region. Flexible electronics necessitates transparent electrodes with high stability, excellent mechanical properties concurrently, high transparency and conductivity. This work demonstrates the development of robust, zinc tin oxide (ZTO) and silver-based room temperature processed flexible, multilayer transparent conductive thin films on polycarbonate substrates. The thin film showed highest average transmittance of 91.2 % in the visible region and sheet resistance of 18.6 Ω/□ with figure of merit 2.14 × 10−2/Ω. Furthermore, the film showed electromagnetic interference shielding effectiveness of 21.76 dB, in the x-band region, which also flaunts its versatile opto-electronic applications. [ABSTRACT FROM AUTHOR]

A very simple and rapid Direct Injection Flame Synthesis (DIFS) method is effectively used to synthesize pure tin oxide (SnO2) and zinc doped tin oxide (Zn:SnO2) nanoparticles from the metallic tin (Sn) and zinc (Zn) powders for the photocatalytic degradation of methylene blue (MB) dye. The DIFS nanoparticles were characterized using XRD, Raman, UV–Vis, FESEM, PL and EDX studies. The X-ray diffraction analysis indicated that the synthesized SnO2 and Zn:SnO2 nanoparticles have pure tetragonal phases and their average crystallite size decreases when Zn was doped with SnO2. Raman study confirmed the various mode of vibrations and the crystal structure of the synthesized nanoparticles. Purity, atomic percentage and chemical composition were analysed using Energy dispersive X-ray analysis and found to be free from impurities. The band gap energy increases from 3.5 to 3.6 eV upon doping which was revealed from the UV–Visible spectroscopic analysis. Photoluminescence analysis confirms the red shifted emission for Zn:SnO2 due to the oxygen deficiency. The CIE chromaticity (x,y) for SnO2 and Zn:SnO2 was calculated from the emission spectra and the co-ordinates represents blue and violet region respectively. Field Emission Scanning Electron Microscopy analysis showed that the pure SnO2 nanoparticles have irregular, agglomerated, nanoflowered and nanoclustered formation whereas Zn:SnO2 nanoparticles has more crystalline, cubical and nanoflake structure. The photocatalytic activity was enhanced due to the presence of Zn in SnO2 under UV light irradiation. The efficiency of MB degradation by SnO2 was found to be 82% and enhanced to 88% upon doping. Thus the Zn doped SnO2 nanoparticles synthesized by DIFS was found to be an effective photocatalyst than the pure SnO2. [ABSTRACT FROM AUTHOR]

A hierarchical reduced graphene oxide (RGO) matrix constituted by both layered and spherical RGO structures was engineered via a spray drying process for immobilizing heterogeneous ZnO and SnO 2 nanoparticles. [Display omitted] In this work, a hierarchical reduced graphene oxide (RGO) supportive matrix consisting of both larger two-dimensional RGO sheets and smaller three-dimensional RGO spheres was engineered with ZnO and SnO 2 nanoparticles immobilized. The ZnO and SnO 2 nanocrystals with controlled size were in sequence engineered on the surface of the RGO sheets during the deoxygenation of graphene oxide sample (GO), where the zinc-containing ZIF-8 sample and metal tin foil were used as precursors for ZnO and SnO 2 , respectively. After a spray drying treatment and calcination, the final ZnO@SnO 2 /RGO-H sample was obtained, which delivered an outstanding specific capacity of 982 mAh·g−1 under a high current density of 1000 mA·g−1 after 450 cycles. Benefitting from the unique hierarchical structure, the mechanical strength, ionic and electric conductivities of the ZnO@SnO 2 /RGO-H sample have been simultaneously promoted. The joint contributions from pseudocapacitive and battery behaviors in lithium-ion storage processes bring in both large specific capacity and good rate capability. The industrially mature spray drying method for synthesizing RGO based hierarchical products can be further developed for wider applications. [ABSTRACT FROM AUTHOR]

This paper presents a humidity sensing based on perovskites nanostructured thin film for improved sensitivity and optical performance. The nickel-doped zinc thin oxide (NZTO) perovskites thin film was used as a sensing material for the humidity sensing application. The NZTO was deposited on borosilicate glass substrates via aerosol-assisted chemical vapour deposition (AACVD) and nickel (Ni) dopant with 2 %mol was added into the precursor solution. The optical performance was investigated by inserting the NZTO into the optical reflection cavity. The cavity comprises NZTO on the glass that placed in a fixed position in front of single-mode fiber (SMF) and SMF was adjusted using x-direction of the 3-axis stage to obtained different cavity lengths. The performance was evaluated from the free-spectral range (FSR) and extinction ratio (ER) of the different cavity lengths. Then, the cavity with an optimized length was placed inside the humidity chamber for sensing applications. The result shows that the optimized cavity length is 100 µm with FSR and ER of 12.05 nm and 7.247 dB. The sensitivity of the humidity sensing is 0.2657 nm/RH% indicates that the NZTO is an excellent candidate for humidity sensing application.