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In this study, titanium dioxide (TiO2) films are prepared using spatial atomic layer deposition (sALD) as an additional compact layer of tin oxide (SnO2) electronic transport layer-based perovskite solar cells. The experimental results show that the deposition of sALD TiO2 films on the fluorine-doped tin oxide substrate improves the haze at mid-long wavelengths, compensating the optical loss caused by the absorption of the TiO2 layer in short-wavelengths. Compared to conventional cells, the insertion of the sALD TiO2 compact layer regardless the thickness shows significantly improved open-circuit voltage, indicating the enhanced hole blocking ability as evidenced by the reduced reverse saturation current. In addition, the change in TiO2 thickness is found to have impacts on short-circuit current, fill factor and hysteresis of the devices. The optimal sALD TiO2 thickness of 10 nm leads to the best cell conversion efficiency of 20.1%, approximately improved by 6% compared to that of the conventional cells. Compared to conventional ALD techniques and other methods, the sALD which does not require vacuum system has the pinhole-free, low-cost, very fast and simple processes, demonstrating the great potential of sALD films for applications in perovskite solar cells.

In this paper, we investigated the performance of an n-type tin-oxide (SnOx) thin film transistor (TFT) by experiments and simulation. The fabricated SnOx TFT device by oxygen plasma treatment on the channel exhibited n-type conduction with an on/off current ratio of 4.4×104, a high field-effect mobility of 18.5 cm2/V.s and a threshold swing of 405 mV/decade, which could be attributed to the excess reacted oxygen incorporated to the channel to form the oxygen-rich n-type SnOx. Furthermore, a TCAD simulation based on the n-type SnOx TFT device was performed by fitting the experimental data to investigate the effect of the channel traps on the device performance, indicating that performance enhancements were further achieved by suppressing the density of channel traps. In addition, the n-type SnOx TFT device exhibited high stability upon illumination with visible light. The results show that the n-type SnOx TFT device by channel plasma processing has considerable potential for next-generation high-performance display application.

Perovskite solar cells (PSC) are becoming increasingly popular owing to its elevated power conversion efficiency. Therefore, in this paper, tin halide perovskite solar cell which is non-toxic in nature is presented with the structure of Sn02:F|ZnSe | CH 3 NH 3 SnI 3 | CuO | Ni and numerically investigated using SCAPS-1D. In the reported PSC, fluorine-doped tin oxide (SnO2:F) is employed as transparent conducting oxide layer, zinc selenide (ZnSe) as electron transport layer (ETL), CH3NH3SnI3 as perovskite absorber layer, copper oxide (CuO) as hole transport layer (HTL) and nickel (Ni) as back contact. We evaluated the PSC performance by varying the thickness (350nm-450nm), acceptor density (3.2 × 1013cm-3-3.2x1017cm-3) and defect density (4.5×1011cm-3- 4.5×1015cm-3) of perovskite absorber layer at temperature of 300K. In addition, the influence of the operating temperature on cell performance of tin halide PSC has studied. It has been demonstrated that, the presented tin halide PSC obtained maximum power conversion efficiency (PCE) 27.26%, open circuit voltage (Voc) 1.0222V, short-circuit current density (J sc ) 31.94mA/cm2, Fill Factor (FF) 83.50% with the thickness (450nm), acceptor density (3.2×1015) and defect density (4.5×1013) of the tin halide perovskite absorber layer. The result of this numerical demonstration indicates that CH3NH3SnI3 has a great potential as an absorber layer of environment friendly PSCs.

This work focuses on 2D device simulation for perovskite/tandem solar cells, aiming to reproduce the experimental current-voltage curves and to explore further steps for efficiency improvements. The results demonstrate that a reasonable J-V curve can be obtained when the indium tin oxide (ITO) layer that interconnects both subcells is treated as either a semiconductor or conductor. In both cases, band to band tunneling and/or additional built-in voltage governed by proper work functions of ITO and tin oxide (SnOx) films are required to obtain the high experimental FFs of >80%. Optical and electrical losses in the tandem device are also addressed by quantum efficiencies (EQE, IQE) and reflectance simulation.

Monolithic perovskite-silicon tandem solar cells using MoOx hole selective contact silicon cell as bottom structure shows a power conversion efficiency of 5.7%. A thin (15nm in thickness) MoOx contact to n-type Si was used instead of a standard p+ emitter to collect holes and the SiOx/n+ poly-Si structure was applied on the rear of the device for direct tunneling of electrons and blocking holes. With this bottom silicon structure, ~14% of devices were manufactured. With this bottom carrier selective silicon cell, tin oxide, and subsequent perovskite structure were deposited to fabricate monolithic tandem solar cells. Monolithic tandem structure without ITO interlayer was also compared to confirm the role of MoOx in tandem cells and this tandem structure shows the power conversion efficiency of 4%. Through this experiment, we have confirmed that the MoOx layer play roles as a passivation layer, hole collecting material, and recombination layer at the same time in the tandem structure.

A waste carbon copies paper (WCCP) can be applied counter electrode, it made from carbon. In this work, The WCCP film counter electrode is particularly focused under the condition rate at 1 g of WCCP. A WCCP film counter electrode will be used to coat on the fluoride-doped tin oxide (FTO) glass and the anode of DSC use TiO 2 film coated on FTO glass. The both electrodes were coated on FTO glass by size 2x3 cm2. The DSC with WCCP film counter electrode is investigated by solar simulator at 250 W/m2. The morphological properties of WCCP film counter electrode were confirmed by X-ray diffraction (XRD) and scanning electron microscope (SEM). There has been found that open circuit voltage (V OC ) was 0.568 V. The short circuit current (I SC ) was 145.23 μA. The use WCCP film counter electrode is sufficient to be built and tested cathode electrode for DSCs application.

The exhaled acetone concentration of diabetic patients is much higher than that of normal persons, which can be used for early warning, large-scale screening, and adjuvant treatment for diabetes. Therefore, a non-invasive exhaled acetone sensor with a low detection limit, high sensitivity, and high reliability is widely studied. Their sensing performance largely depends on the chemical composition of sensing materials, surface modification, the microstructure of the sensing layer. In this paper, Tin oxide (SnO 2 ) nanocrystalline composed inverse opal structure were successfully prepared, using polystyrene microspheres as templates, as a sensing material for an acetone gas sensor. Compared with pure SnO 2 prepared by the hydrothermal method, inverse opal SnO 2 has a much higher response at a low concentration of 500ppb-10ppm, Up to 5.6 response at 1ppm(240°C), which is already suitable for diabetes screening without doping noble metal. The improvement of gas sensitivity is mainly due to the small size of the SnO 2 nanoparticles and the pore structure composed of the nanocrystalline. The relatively high response, fast response and recovery speed, and good stability make it a promising gas sensor material for screening and monitoring of diabetes.

In this paper, a novel architecture of zinc oxide (ZnO) buffer layered lead sulphide (PbS) colloidal quantum dot (CQD) solar cell is proposed. The proposed CQD solar cell is of the architecture of glass substrate: fluorine tin oxide (FTO)/ZnO/titanium dioxide (TiO 2 )/PbS- tetra-butyl ammonium iodide (PbS-TBAI)/PbS-1, 2-ethanedithiol (PbS-EDT)/gold (Au) – contacts with power conversion efficiency (PCE) of 15.28% and is modeled and investigated in solar cell capacitance simulator (SCAPS). Here FTO is the oxide layer (OL), TiO 2 is used as an electron transport layer (ETL), PbS colloidal quantum dots (CQDs) layer treated with PbS-TBAI serve the purpose of generating electron-hole pairs whenever a solar cell is exposed to solar insolation and PbS CQDs layer treated with EDT is used to extract the holes. The impact of varying layer thicknesses on PCE, open-circuit voltage (V oc ), short circuit current density (J sc ) and fill factor (FF) is also discussed in the paper. The quantum efficiency (QE) of the proposed solar cell reveals that the proposed PbS- CQD solar can capture a wider range of incident light wavelengths across the broader range of solar spectrum depicting that this research effort can become a useful guide in the future fabrication of high efficient PbS CQD solar cells.

In this paper, we reported ap-channel tin-oxide (SnO) thin-film transistor (TFT) by introducing aluminum (AI) dopant in the SnO channel layer. An extremely high field-effect mobility $(\mu_{\text{FE}}$ ) of 8 cm2/V·s and an on-to-off current ratio $(I_{\text{on}}/I_{\text{off}})$ of ~103 were obtained in this p-channel Al-doped SnO (A1:SnO) TFT. Furthermore, the device performances of the Al:SnO TFT including the $I_{\text{on}}/I_{\text{off}}$ and subthreshold swing (SS) were greatly improved by fluorine plasma treatment (FPT) on the Al:SnO channel layer. In addition, in order to study the channel plasma effect on the device performances, TCAD simulation was carried out based on the p-channel Al:SnO TFT by introducing the density of state (DOS) model. The simulation results indicated that the device performance enhancements were further achieved because the attributes of acceptor-like Gaussian defect states and donor-like band-tail state were modified during the FPT.

In the present work an effort has been made to understand the effect of nanofillers on service aged transformer oil. Semiconducting tin oxide nanoparticles were dispersed into aged transformer oil samples with a weight percentage of 0.01% using magnetic stirring and sonication processes. The breakdown voltage of tin oxide filled aged oil samples were measured and compared with unfilled sample. In addition to this fluorescent spectroscopic analysis were done to understand the degradation in aged transformer oil.

Vertical glass facade buildings, such as skyscrapers, have significant potential for generating electricity using solar window technologies, such as SwitchGlaze, a switchable photovoltaic window. This window contains a perovskite layer that absorbs visible, infrared, and UV light. To commercialize this and other perovksite solar cells, it is essential to optimize a scalable production process, such as electrodeposition, which can controllably fabricate stable transport layers. This technique can then be used to fabricate back contact solar devices to decrease delamination occurrence and allow for more sunlight to directly interact with the perovskite and increase device efficiency. Nickel oxide (NiO x ) and tin oxide (SnO 2 ), are especially promising transport layers due to their high stability and electron mobility, respectively. Both can be fabricated at room temperature and are also suitable for window technology due to their high transparency. A three-electrode system was used to determine which electrolyte concentrations, electrodeposition times, current densities, and annealing times would electrodeposit the most uniform, thinnest, and smoothest transport layers. The Keyence Profilometer, Dektak8 profilometer, and ultraviolet-visible spectroscopy were used to measure film thickness, surface roughness, and observe deposited oxidation states.

This paper presents an elaboration of thin films dedicated to photovoltaic systems. Zinc oxide (ZnO) on fluorine tin oxide (FTO) coated glass substrates are one of the best semiconductors oriented to solar cell preparations. In this study, the ZnO solution is performed with some sol concentration (0.1 M to 0.5 M) to verify its effect on thin-film samples. On the other hand, samples prepared are analyzed and characterized in structural and the optical properties using different techniques as ultraviolet-visible (UV-vis) spectrometry, Fourier transform infrared spectroscopy (FT-IR) and X-ray diffraction (XRD). This work showed the variation of the energy gap (Eg) values. The Eg values allow us to ensure good solar cells. In this study, the thin films prepared showed that the energy gap values are ranged between 3.29 eV and 3.4 eV. These results led us to confirm the possibility of having an easy passage of the electrical current. In addition, the transmittance spectra of the ZnO/FTO thin films showed an average of ∼75% in the visible region and presented sharp absorption edges at 375 nm. The experimental preparation ensures a good decision about electrical energy production which based on the photovoltaic systems.

The analysis of dissolved gases in insulation oil is of great significance to transformer status evaluation. In this paper, a chromatographic detector based on the nano-tin oxide fiber as well as a chromatography system is developed. The mechanism of the sensor for detecting six component feature gases (i.e., H2, CO, CH4, C2H4, C2H6, and C2H2) in transformer oil is expounded, on basis of which the exponent-logarithmic model between conductance and gas concentrations is proposed. Then, the repeatability and accuracy of the nano-tin oxide detectors are tested. The experimental results show that the gases mixture can be separated well by the designed gas chromatography system, and six component gases mixture detection can be realized by the developed detector. Meanwhile, by using the proposed model, high precision of dissolved gas measurement can be achieved, thus the validity of the presented model is verified. Moreover, compared with other chromatographic detectors, i.e., flame ionization detector, the only carrier gas needed for the nano-tin oxide chromatographic detector is the synthetic air, the hardware cost and complexity of system are reduced largely, showing promising applicable value in the engineering practice.

In this paper, we report the Photodetector based on SnO 2 /CH 3 NH 3 PbI 3 based heterojunction diode on Indium doped tin oxide (ITO) substrate. The perovskite CH 3 NH 3 PbI 3 and metal oxide SnO 2 are synthesized using the sol-gel method. The synthesized metal oxide SnO 2 and perovskite CH 3 NH 3 PbI 3 characterized using X-Ray diffraction (XRD), High resolution Scanning Electron Microscope (HRSEM), UV visible and Photo luminance Spectroscopy. XRD result confirms the formation rutile tetragonal crystalline structure of SnO 2 and Tetragonal crystalline structure of perovskite CH 3 NH 3 PbI 3 , and HRSEM image shows the uniform distribution of particles. An efficient photoluminescence band is observed at ~795 nm in SnO 2 /CH 3 NH 3 PbI 3 thin films at ambient temperature when excited with 473 nm wavelength light Finally, SnO 2 /CH 3 NH 3 PbI 3 based heterojunction diode is investigated for an electrical and optical response using fabricated ITO/SnO 2 /CH 3 NH 3 PbI 3 /Ag Photodetector device.

Semiconductor Metal Oxide (SMO) films are widely used in gas sensors application. The SMO film is typically heated to an operating temperature of 100°C and above to sense the target gases, using a microheater. The stability and reliability of the microheater and the SMO is critical for making a sensing product out of it. The thermal stability of the dielectric films used in the integration along with the degradation of the sensitive film is the aim of our study. Exposure to high temperature, causes the different layers to expand differently. These layers have different thermal expansion coefficient, that when contracting cause the films to crack.

In this study, the tin oxide (SnO 2 ) based gas sensor with micro heater embedded (working temperature lower than 100 °C) was developed, and the ethanol-sensing characteristic was also discussed. The mico heater presented a fast, stable heating source while gas sensing process. The result indicated that the gas sensor had more than 88% in sensitivity regarding to the 10 ppm and 30 ppm ethanol gas sensing.

Solar energy is a significant renewable source of energy for current global scenario. Being abundant in nature researchers are striving to conceive and improvise enhancement in performance. In this paper an optimization of perovskite solar cell is carried out to improve efficiency and fill factor. The proposed solar cell is modeled and simulated using SCAPs software. The designed solar cell is 35.83% efficient in terms of power conversion efficiency. The performance of existing and optimized solar cell design is comparatively analyzed in terms of performance parameters. The parameters of perovskite solar cells (PSC) design are evaluated using Copper iodide (CuI) as hole transport layer and Tin oxide (SnO2F) as Transparent conducting oxide. The results show that the concept of all the designs is almost identical but the material and morphology in implementation affects performance greatly in terms of PCE.

Tin Oxide (SnO2) thin film with thickness of 300 nm is fabricated on glass substrate (2 cm × 2 cm) utilizing vacuum evaporation by fixing vacuum pressure of 2.4 × 10 −6 torr and deposition rate of 0.5 A/sec. Substrate temperature is fixed at 300°C and annealed for 15 minutes at 350°C. Aluminum (Al) and Copper (Cu) doping are performed by stacked layer method and further characterized by X-ray diffractometer (XRD) and UV-VIS-NIR spectrophotometer. XRD patterns revealed of Al and Cu doped SnO2 thin film proved it as a polycrystalline with cubic phase and variable miller indices at peak XRD intensity. Optical properties like transmittance, dielectric constant, reflectance, energy bandgap and refractive index are also calculated and found something promising. Transmittance in near-infrared region for undoped film is approximately 70% and for both Al and Cu doped films it is below 35%. Reflectance gets higher as the percentage of Al and Cu doping increase; energy bandgap falls from 3.72 eV to 3.42 eV and both refractive index and dielectric constant get higher as the percentage of Al and Cu doping enhances.

Semiconductor metal oxide films have been used in sensing-based applications, and they are typically prepared by vacuum deposition techniques. In this study, we used solution-processed semiconductor metal oxides to investigate their sensitivity for cations in aqueous solution. Specifically, solution-processed tin(IV) oxide (SnO 2 ), titanium dioxide (TiO 2 ) and a composite of SnO 2 /TiO 2 were deposited on fluorine-doped tin oxide (FTO) glass and these were tested for their chemiresistive properties when exposed to cationic species in solution. Techniques such as grazing incidence X-ray diffraction (GIXRD), scanning electron microscopy (SEM), atomic force microscopy (AFM), and the surface profiler were utilized to characterize the metal oxide films.

In this work, we studied the electrical properties of films of mixed zinc and tin oxides obtained by low-temperature pyrolysis. The temperature dependences of the resistance of ZnO-SnO 2 films, measured in the range from room temperature to 300 °C, showed the difference between the heating and cooling curves, which is explained by two competing processes - thermal generation of electrons and adsorption of oxygen particles on the surface of the oxide film. Using the slope of the linear section on the Arrhenius plot, we calculated the activation energy of conductivity, which amounted to 1.1 eV. Based on the results of energy dispersive analysis, it was concluded that the material of the obtained films is zinc oxide with the addition of tin oxide.

This paper describes the methodology of synthesis and characterization in nanostructured samples based on alumina and tin oxide for potential applications as gas sensors. In the process 99.95% purity aluminum sheets were used, in which an anodizing process was applied to form the nanoporous templates of alumina. Subsequently, the samples with the alumina formed are used to introduce tin material by electrodeposition, which were sintered at 400, 450, 500 and 550 °C, in order to analyze the formation of stannic oxide. The characterization of the samples was carried out through scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction and capacitive tests. The SEM images analyzed by Image J present a homogenous distribution of pores with a resulting porosity level of 18.6%. The morphological parameters obtained from these images indicate a pore size of average diameter at 24.0 nm, and a nanoporous film thickness of 12.0 µm. The resulting value of the pore density in the samples was 4.46x10^10 pores/cm2. The analysis of the X-ray diffraction patterns indicates the formation of the nanocrystalline rutile phase structure, mainly for samples sintered at 550 °C. The presented results show that the methodologies used in the synthesis of tin oxide nanowires produce good quality nanostructures with potential applications as gas sensors.

This paper presents the fabrication and thickness analysis of TiO 2 on Fluorine-doped Tin Oxide (FTO) glass for Dye-Sensitized Solar Cell (DSSC). The TiO 2 layer was deposited on the cleaned FTO glass using doctor blade technique and the thickness of the TiO 2 were controlled by with different layers of adhesive tape. This results showed that the two-layer with thickness 15.09 μm of adhesive tape achieved the highest efficiency of 4.73 %, and followed by three-layer and one-layer at 3.64% at 2.32 % respectively.

Recently developed Silver/Tin oxide contact material Ag/SnO 2 14 WPA has been proven to fulfill AC contactor switching requirements as service life, make capacity, and overtemperature behavior in a very satisfactory way. Based on these experiences, early failures with an additional AC4 electrical endurance test at app. 60% of service life goal were unexpected and triggered in depth analytical evaluations to fix root causes. Applying microsections, microtome sectioning, ultrasonic analysis, optical and scanning electron microscopy (SEM) combined with energy dispersive x-ray spectroscopy (EDX) two different main root causes could be identified. Mixed oxide layers with high amounts of phosphorous as well as some layers with iron oxide were detected on the contact surface, probably originating from excess braze alloy rising the contact tip side and splitter plate splashing and evaporation, respectively. These contaminants on the surface react with tin oxide leading to thick mixed oxide layers causing probably severe arcing on make. This leads to high contact erosion and finally welding of the contacts.

This paper report the synthesis of pure SnO 2 , doped SnO 2 nanofibers with 3wt% of Aluminium (Al-SnO 2 ) and 3wt% of Zinc (Zn-SnO 2 ) by one step electrospinning method. Pure and doped-SnO 2 were deposited on fluorine doped tin oxide (FTO) coated conducting glass. The optimum calcination of the nanofibers is at 700°C. The variations in the structural, morphological and optical properties of the of pure and doped-SnO 2 nanofibers were studied through FESEM, XRD and UV-vis spectroscopy. The UV-vis spectra indicated a maximum absorption band shown at 300nm and the highest average transmittance around 64%. The structure and optical properties of SnO 2 , Al-Sno 2 and Zn-SnO 2 nanofibers indicate that this method is promising and that future work is warranted to treat and immerse the nanofibers with DMF solution to reinforce the adhesion between nanofibers and substrate so that it can be used in electronics devices.

A photosensor is an electronic component that detects the presence of visible light, infrared radiation, and/ or ultraviolet radiation. A photosensor which changes its electrical capacitance in the presence of visible light was developed based on the photo-dielectric effect of Cadmium Sulphide (CdS). A thin layer of CdS was deposited on Fluorine-doped Tin Oxide glass using chemical bath deposition technique. The optimum photo-dielectric behaviour was observed for chemical bath temperature between $40-45^{\circ}\mathrm{C}$. After annealing the deposited film at $180-200^{\circ}\mathrm{C}$, they have shown a band gap in the range of 2.30– 2.40 eV. Photo-capacitance and photoconductivity in dark and visible light illumination showed a significant change, indicating these films are suitable for photo sensing applications.

We have investigated a perovskite photo-sensors with electron-beam evaporated titanium dioxide (TiO 2 ) film as an electron transport buffer layer. The TiO 2 films have been deposited on indium-doped tin oxide (ITO) glass substrate at room temperature. Then, prepared TiO 2 films are annealed at different temperatures of between room temperature and 500°C. Device structure is ITO/TiO 2 /Perovskite layer/2,2,7,7-tetrakis (N,N-di-p-methoxyphenylamine)-9,9-spirobifluorene/Au. Before and after annealing process, TiO 2 films have changed from an amorphous to crystalline structure mixed with anatase and rutile phases. For a sensing characteristics, a ratio of photo- and dark-current was 1.1×103 without annealing condition. It is assumed that a flat device structure and a larger photocurrent under illumination are effective to reduce carrier generation site.

Low stability, less efficiency and high cost material of the solar cell make its commercialization and manufacturing less point of attention for many researcher and industrial investor. However, the main focus of this work is to compare the investigated material i.e., CZTS with existing materials i.e., amorphous, CIGS and perovskite solar cells with respect to efficiency, cost and stability as it is one of the keen interests in photovoltaic (PV) research field. In this paper, we have presented a highly efficient, highly stable and less costly thin film solar cell with novel material i.e., Copper Zinc Tin Sulphide (CZTS) that holds a conversion efficiency, η of 18.68% with supporting short current density, Jsc= 25.258mA/cm2, open circuit voltage, V oc =0.8787 V and fill factor, FF=84.17%. Different window layer materials along with various buffer layer materials is tested and founded that fluorine tin oxide (FTO) and Indium sulphide (In2S3) are best performing candidates among all other materials. Moreover, effect of high temperature on CZTS electrical parameter is analyzed and drop in the η is observed when the temperature of the device is increased.

We newly prepared indium-gallium-tin-oxide (In-Ga-Sn-O) thin film by solution process for TFT active layer. The spin-coated IGTO film exhibits an excellent transparency that is over 90% at the spectral range from 290nm to 800nm. The saturation filed effect mobility of bottle-gate and top-contact IGTO TFT can be increased from 10 cm2/Vs to 13 cm2/Vs by adjusting the elements ratio of In and Sn. The ΔV TH was 0.8V and -1.8V respectively under positive gate bias stressing (PGBS) and negative gate bias stressing (NGBS) with stress time for 3600s. The spin-coated IGTO film pre-heated in water vapor performed more stable in gate voltage forth-back scanning and obtained higher on-current than those not preheated by water vapor. In addition, the short channel device has better performance in our study. By comparison, solution-process based IGTO TFT performs better than many IGZO TFTs. The results may provide a new choice for oxide-based TFTs, displays and transparent electronics.

Hydrogel microcapsules provide well-defined and biocompatible platforms for 3D cell culture, which is greatly desired for replacing, or enhancing the function of damaged human tissue and in vitro tissue regeneration. Since Alginate-poly-L-lysine alginate microcapsules can provide a liquified environment for biomaterials, traditional fabrication methods such as microfluidic gelation can tune the size and biochemical properties of hydrogel microcapsule, but still, undergo tremendous challenges while tuning the morphology of the hydrogel microcapsules. In this work, we proposed a novel approach to fabricate Janus Alginate-Poly-L-lysine Alginate microcapsule with controllable shape and size based on a two-step hydrogel electrodeposition method. The microelectrode device (fluorine-doped tin oxide (FTO) glass) was etched into two insulating parts by laser processing. After the first step, the electrodeposition solution was removed by adding HEPES solution. During secondary electrodeposition, a higher voltage was employed, since the entrapped hydrogel and unremoved HEPES solution remains upon the surface of the fluorine-doped tin oxide (FTO) glass. After the two-step deposition, the 2D hydrogel Janus structures were detached from the FTO glass. Then they were immersed in Poly-L-lysine solution. Then the 3D Alginate-poly-L-lysine alginate (APA) microcapsules were successfully fabricated and incubated for further observation. We have demonstrated a successful encapsulation of HepG-2 cells in the half of the APA hydrogel microcapsule and the cells are cultured for several days and Janus APA microcapsules are embedded with fluorescence-labelled and non-labelled HepG2 cells to monitor the cell morphology, distribution, as well as their proliferation.

A thin layer of Al 2 O 3 at the back of CdSe x T e1-x /CdTe devices is shown to passivate the back interface and drastically improve surface recombination lifetimes and photoluminescent response. Despite this, such devices do not show an improvement in open-circuit voltage (VOC.) Adding a p+ amorphous silicon layer behind the Al 2 O 3 bends the conduction band upward, reducing the barrier to hole extraction and improving collection. Further optimization of the Al 2 O 3 , amorphous silicon (a-Si), and indium-doped tin oxide (ITO) layers, as well as their interaction with the CdCl 2 passivation process, are necessary to translate these electro-optical improvements into gains in voltage.

In this work, we investigate an fabricating route of solution-processed thin-film transistors (TFTs). The high-k dielectric layers of aluminum oxide (AlO) were optimized through hydrogen peroxide (H 2 O 2 ). With Zn incorporation in tin oxide (SnO) semiconductor layer, the ZnSnO TFT with a field effect mobility of 4.3 cm2·V−1·s−1, a threshold voltage of 2 V, a subthreshold swing of 0.16 V/dec and an on/off ratio of 106.

In this work, chemiresistive devices based on electrospun nanofibers of tin oxide are developed and their performance for detecting low levels of nitrogen dioxide in air is assessed. The influence on the sensor detection properties of the operation temperature, the load of tin oxide nanofibers and the presence of graphene in the active layer is investigated. It is found that tin oxide nanofibers are highly sensitive towards nitrogen dioxide and the optimal operation temperature lies in the range of 150-200 oC, while the addition of graphene leads to improved sensitivity at temperatures below 100 °C.

A bulk acoustic wave gas sensor system based on high temperature stable piezoelectric transducers and thin metal oxide sensor films is developed. The simultaneous determination of changes in electrical and gravimetric properties of tin oxide (SnO 2 ), titanium oxide (TiO 2 ) and praseodymium doped ceria (PCO, Pr x Ce 1-x O 2 with x = 0.1 and 0.2) sensor films enables to distinguish methane and ethylene in inert gas atmospheres (argon) at temperatures up to 900 °C.

Transparent conductive oxides are used in many technologies and it is important to understand their interfacial chemical reactions. Here, we use recently developed thermomechanical cleaving and X-ray photoelectron spectroscopy to probe oxidation states at the SnO 2 interface of CdTe solar cells. We show that tin oxide promotes the formation of nanometer-scale oxides of tellurium and sulfur, largely during CdCl 2 /O 2 activation. Surprisingly, in copper-doped devices, relatively low temperature anneals (180-260 °C) to diffuse and activate copper acceptors also cause significant oxidation changes at the front interface, providing a heretofore missing aspect of how back contact processes can modify device transport, recombination, and performance. For Group V-doped devices, this same oxidation process causes segregation of the dopants to the SnO 2 interface in their oxidized states, implying that adjacent regions in the absorber have been depleted of dopants. Intriguingly, we demonstrate that because of their layered, van der Walls-bonded crystal structure, spatially segregated Group V oxides may represent a mechanically weak layer in a finished device.

Tin oxide (SnO 2 ) is an n-type wide band-gap semiconductor with excellent properties such as optical, electrical and chemical properties. In this research, SnO 2 thin films were grown on m-plane sapphire substrates by mist chemical vapor deposition. However, it was difficult to deposit high quality SnO 2 films because of the large lattice mismatch and the large difference in the thermal expansion coefficient between the SnO 2 film and the sapphire substrate. To improve the quality of SnO 2 films, we inserted a SnO 2 buffer layer to solve the lattice mismatch problem between the substrate and the film. We found that the surface morphologies of SnO 2 films with the buffer layers were smoother than the films without the buffer layers. Furthermore, the full width at half maximum (FWHM) of an X-ray $\omega$ -rocking curve for the SnO 2 thin film was reduced obviously. Thus, the crystal quality of SnO 2 films was much improved by introducing the buffer layers between the substrate and the thin films.