Volume of precursor solution effect on the properties of SnO<Subscript>2</Subscript> thin films prepared by nebulized spray pyrolysis technique

Undoped SnO₂ thin films have been deposited on amorphous glass substrates with different precursor solution volume (10, 15, 20 and 25 ml) using simple and cost-effective nebulized spray pyrolysis technique. The influence of precursor solution on structural, optical, photoluminescence and electrical properties had been studied. The X-ray diffraction spectra prove the polycrystalline nature of SnO₂ with tetragonal structure. All the films show a preferred growth orientation along (110) diffraction plane. The average transmittance of SnO₂ thin films varied between 82 and 75% in the visible as well as IR region. The band gap energy decreases from 3.74 to 3.64 eV corresponding to direct transitions with the precursor solution volume had increased from 10 to 20 ml and then increased as 3.72 eV for 25 ml. SEM pictures demonstrated polyhedrons like grains. EDX confirmed the existence of Sn and O elements in all the prepared SnO₂ thin films. Photoluminescence spectra at room temperature revealed that the four emission bands in all the samples such as sharp dominant peak at 361 nm with shoulder peak at 377 nm (UV region), a broad and low intensity peak at 492 nm (blue region) and 519 nm (green region). The electrical parameters were examined by Hall effect measurements, which demonstrated that the film prepared at 20 ml precursor solution volume possess minimum resistivity 2.76?×?10^?3 Ω-cm with activation energy 0.10 eV and maximum figure of merit 1.54?×?10^?2 (Ω/sq)^?1.     

Highly transparent and conductive indium tin oxide thin films for solar cells grown by reactive thermal evaporation at low temperature

Transparent conductive tin-doped indium oxide (In₂O₃:Sn, ITO) thin films with various Sn-doping concentrations have been prepared using the low cost reactive thermal evaporation (RTE) technique at a low growth temperature of ~160 °C. The structural characteristics, optical and electrical properties of the ITO thin films were investigated. These polycrystalline ITO films exhibited preferential orientation along (222) plane and possessed low resistivities ranging from 3.51 to 5.71 × 10^?4 Ω cm. The decreased mobility was attributed to the scattering by ionized and neutral impurities at high doping concentrations. The optimized ITO thin film deposited with 6.0 wt% Sn-doping concentration exhibited a high average transparency of 87 % in the wavelength range of 380–900 nm and a low resistivity of 3.74 × 10^?4 Ω cm with a high Hall mobility of 47 cm² V^?1s^?1. A hydrogenated amorphous silicon and silicon–germanium (a-Si:H/a-SiGe:H) double-junction solar cell fabricated with the RTE-grown ITO electrodes presented a conversion efficiency of 10.51 %.     

Influence of the annealing technique on the properties of Li ion-conductive Li1.3Al0.3Ti1.7(PO4)3 films

Li_1.3Al_0.3Ti_1.7(PO₄)₃ films were comparatively prepared by rapid thermal annealing (RTA) and conventional furnace annealing(CFA). The phase identification and surface morphology of the prepared films were characterized by X-ray diffraction and scanning electron microscopy. The electrochemical window, ionic conductivity, activation energy, and electronic conductivity were conducted by cyclic voltammetry, electrochemical impedance spectroscopy, and four-probe technique. The results show that the films prepared by RTA and CFA are homogenous and crack-free. The film prepared by RTA shows smaller grains and is denser than the one prepared by CFA. The electrochemical windows of the two films are beyond 2.4 V. The ionic conductivities of the films prepared by RTA and CFA are 2.7?×?10^?6 S cm^?1 and 1.4?×?10^?6 S cm^?1, respectively. The activation energy of the film prepared by RTA is 0.431 eV, which is slightly smaller than the one prepared by CFA. The electronic conductivity of the two films is about 10^?10 S cm^?1.     

Swift heavy ion provoked structural, optical and electrical properties in SnO2 thin films

SnO₂ thin films grown on glass substrates at 300 ^°C by reactive thermal evaporation and annealed at 600 ^°C were irradiated by 120 MeV Ag⁹⁺ ions. Though irradiation is known to induce lattice disorder and suppression of crystallinity, we observe grain growth at a certain fluence of irradiation. X-ray diffraction (XRD) revealed the crystalline nature of the films. The particle size estimated by Scherrer’s formula for the irradiated films was in the range 10–25 nm. The crystallite size increases with increase in fluence up to 1×10¹² ions?cm^?2, whereas after that the size starts decreasing. Atomic force microscope (AFM) results showed the surface modification of nanostructures for films irradiated with fluences of 1×10¹¹ ions?cm^?2 to 1×10¹³ ions?cm^?2. The UV–visible spectrum showed the band gap of the irradiated films in the range of 3.56 eV–3.95 eV. The resistivity decreases with fluence up to 5×10¹² ions?cm^?2 and starts increasing after that. Rutherford Backscattering (RBS) reveals the composition of the films and sputtering of ions due to irradiation at higher fluence.     

Gelatin-HCl biomembranes with ionic-conducting properties

Gelatin-HCl protonic gel polymer electrolytes were obtained by crosslinking with formaldehyde in the presence of hydrochloric acid and glycerol as plasticizer and characterized in present study. The ionic conductivity measurements revealed the best value of 5.35?×?10^?5 S cm^?1 at room temperature. Factorial design analysis showed that influence of glycerol is more pronounced than influence of acid on ionic conductivity values. Moreover, the 90 % transparent membranes evidenced a linear increase of ionic conductivity values of 5.35?×?10^?5 S cm^?1 at 26.5 °C to 5.77?×?10^?4 S cm^?1 at 82.8 °C following Arrhenius type mechanism of charge mobility.     

Influence of nano-sized fumed silica on physicochemical and electrochemical properties of cellulose derivatives-ionic liquid biopolymer electrolytes

Nanocomposite biopolymer electrolyte was prepared by solution-casting technique. Carboxymethyl cellulose from kenaf bast fibre, ammonium acetate, (1-butyl)trimethyl ammonium bis(trifluoromethylsulfonyl)imide ionic liquid and silica nanofiller was used to prepare the biopolymer electrolyte samples. The films were characterized by Fourier transform infrared spectroscopy, electrochemical impedance spectroscopy, scanning electron microscopy, transference number measurement and linear sweep voltammetry. The interactions of doping salt, ionic liquid and inorganic nanofiller with the host biopolymer were confirmed by FTIR study. The highest conductivity achieved was 8.63 × 10^?3 S cm^?1 by the incorporation of 1 wt% of SiO₂ at ambient temperature. The electrochemical stability of the highest conducting sample was stable up to 3.4 V, and the ion transference number in the film was 0.99.     

Field enhanced Li ion conduction in nanoferroelectric modified polymer electrolyte systems

Nanocomposite polymer electrolyte (NCPE) films based on polyethylene oxide (PEO) complexed with lithium perchlorate (LiClO₄) and nanosized ferroelectric ceramic fillers such as BaTiO₃, SrTiO3 have been prepared using solution cast technique. The films showed very good mechanical stability when exposed to ambient atmospheres for prolonged periods. Lithium ion transport studies revealed that the conductivity is predominantly ionic. The effect of electric field on ionic conductivity of NCPE films was investigated. One order enhancement in conductivity due to the field was observed at 323 K. NCPE films exhibited conductivity of 3.46?×?10^?5 Scm^?1 at 323 K. NCPE films were characterized using differential scanning calorimetry (DSC) and X-ray diffraction (XRD) technique. The DSC and XRD studies revealed reduced crystallinity which confirmed the higher amorphous phase and hence the improved ionic conductivity.     

Structural,photoconductive, thermoelectric and activation energy measurements of V-doped transparent conductive SnO<Subscript>2</Subscript> films fabricated by spray pyrolysis technique

This report investigated the structural, optical and electrical properties of V-doped SnO₂ thin films deposited using spray pyrolysis technique. The SnO₂:V films, with different V-content, were deposited on glass substrates at a substrate temperature of 550°C using an aqueous ethanol solution consisting of tin and vanadium chloride. X-ray diffraction studies showed that the SnO₂:V films were polycrystalline only with tin oxide phases and the preferred orientations are along (1 1 0), (1 0 1), (2 1 1) and (3 0 1) planes. Using Scherrer formula, the grain sizes were estimated to be within the range of 25–36 nm. The variation in sheet resistance and optical direct band gap are functions of vanadium doping concentration. Field emission scanning electron microscopy (FESEM) revealed the surface morphology to be very smooth, yet grainy in nature. Optical transmittance spectra of the films showed high transparency of about ～69–90% in the visible region, decreasing with increase in V-doping. The direct band gap for undoped SnO₂ films was found to be 3.53 eV, while for higher V-doped films it shifted toward lower energies in the range of 3.27–3.53 eV and then increased again to 3.5 eV. The Hall effect and Seebeck studies revealed that the films exhibit n-type conductivity. The thermal activation energy, Seebeck coefficient and maximum of photosensitivity in the films were found to be in the range of 0.02–0.82 eV (in the low-temperature range), 0.15–0.18 mV K^?1 (at T = 350 K) and 0.96–2.84, respectively.     

氧氩比对SnO2/Ag/SnO2透明导电膜光电性能的影响

在室温及不同的氧氩比条件下,采用射频磁控溅射Ag层和直流磁控溅射SnO₂层,在载玻片衬底上制备出了SnO₂/Ag/SnO₂多层薄膜.用霍尔效应测试仪、四探针电阻测试仪和紫外-可见-近红外光谱仪等表征了薄膜的电学性质和光学性质.实验结果表明:当氧氩比为1:14时,所制得的薄膜的光电性质优良指数最大,为1.69×10^-2 Ω^-1;此时,薄膜的电阻率为9.8×10^-5 Ω·cm,方电阻为9.68 Ω/sq,在400~800 nm可见光区的平均光学透射率达85%;并且,在氧氩比为1:14时,利用射频磁控溅射Ag层和直流磁控溅射SnO₂层在PET柔性衬底上制备出了光电性质优良的柔性透明导电膜,其在可见光区的平均光学透过率达85%以上,电阻率为1.22×10^-4 Ωcm,方电阻为12.05 Ω/sq.     

Studies of some physical properties of PrFe0.7Ni0.3O3 thin films after 200 MeV Ag15+ irradiation

PrFe_0.7Ni_0.3O₃ thin films (thickness ~ 200 nm) were prepared by pulsed laser ablation technique on LaAlO₃ substrate. These films were irradiated with 200?MeV Ag¹⁵⁺ ions at various fluencies, ranging from 1 × 10¹¹ to 1 × 10¹² ions/cm². These irradiated thin films were characterized by using X-ray diffraction, dc conductivity, dc magnetization and atomic force microscopy. These films exhibit orthorhombic structure and retain it even after irradiations. The crystallite size (110–137?nm), micro strain (1.48 × 10^?2–1.75 × 10^?2 line^?2?m^?4) and dislocation density (79.7 × 10¹⁴–53.2 × 10¹⁴ line/m²) vary with ion fluencies. An enhancement in resistivity at certain fluence and then a decrease in its value (0.22175–0.21813?Ω?cm) are seen. A drastic change in observed magnetism after ion irradiation is seen. With ion irradiation, an increase in surface roughness, due to the formation of hillocks and other factors, is observed. Destruction of magnetic domains after irradiation can also be visualized with magnetic force microscopy and is in close agreement with magnetization data. The impact on various physical properties in these thin films after irradiation indicates a distortion in the lattice structure and consequently on single-particle band width caused by stress-induced defects.     

Effect of Al doping on structural,optical and electrical properties of SnO2 thin films synthesized by pulsed laser deposition

Aluminium-doped (Al = 0–5?wt.%) SnO₂ thin films with low-electrical resistivity and high optical transparency have been successfully synthesized by pulsed laser deposition technique at 500 °C. Structural, optical and electrical properties of the as-deposited and post-annealed thin films were investigated. X-ray diffraction patterns suggest that the films transform from crystalline to amorphous state with increasing aluminium content. The root mean square (R_q) surface roughness parameter, determined by atomic force microscopy decreases upon annealing of the as-deposited film. While resistivity of the film is the lowest (9.49 × 10^?4 Ω-cm) at a critical doping level of 1?wt.% Al, optical transparency is the highest (nearly 90%) in the as-deposited condition. Temperature dependence of the electrical resistivity suggests that the Mott’s variable range hopping process is the dominant carrier transport mechanism in the lower temperature range (40–135 K) for all the films whereas, thermally activated band conduction mechanism seems to account for conduction in the higher temperature region (200–300 K).     

Cu-supported carbon networks containing SnO<Subscript>2</Subscript> as three-dimensional anodes for lithium-ion batteries

Cu-supported SnO₂@C composite coatings constructed by interconnected carbon-based porous branches were fabricated by annealing Cu foils with films formed by knife coating DMF solution containing SnCl₂, polyacrylonitrile (PAN), and poly(methyl methacrylate) (PMMA) on their surface in vacuum. The carbon-based porous branches consist of amorphous carbon matrices, SnO₂ nanoparticles with a size of 30–100 nm mainly encapsulated inside, and many micropores with a size of 1–5 nm. The three-dimensional (3D) porous network structures of the SnO₂@C composite were achieved by volatilization of PMMA and pyrolysis of SnCl₂. The SnO₂@C composite coatings demonstrate good cyclic performance with a high reversible capacity of 642 mA h g^?1 after 100 cycles at a current density of 50 mA g^?1 without apparent capacity fading during cycling and excellent rate performance with a capacity of 276 mA h g^?1 at a high current density up to 10 A g^?1.     

Magnetic behaviour and DCEMS study of SnO2 films implanted with 57Fe

Fe implanted SnO₂ films (5 × 10¹⁶ and 1 × 10^{17 57}Fe ions/cm²) characterized by conversion electron Mossbauer spectroscopy (CEMS) are reviewed. The substrate temperatures affect the growth of precipitated iron oxides. The Fe ion implanted film at room temperature (RT) shows no Kerr effect and no magnetic sextet in CEM spectra. The SnO₂ film implanted with ⁵⁷Fe at the substrate temperature of 300 °C show a small Kerr effect although the magnetic sextet is not observed, but post-annealing results in the disappearance of the Kerr effect. This magnetism is considered to be due to defect induced magnetism. Some samples were measured by CEMS at 15 K. SnO₂ (0.1 at %Sb and 3 at %Sb) films, implanted at 500 °C and the post-annealed samples, show RT ferromagnetism due to formation of clusters of magnetite and maghemite, respectively. The layer by layer analysis of these films within 100 nm in thickness has been done by depth sensitive CEMS (DCEMS) using a He + 5 % CH₄ gas counter. The structures and compositions of Fe implanted SnO₂ films, and the effects due to post-annealing were investigated.     

Poly (ethylene oxide) (PEO)-based,sodium ion-conducting‚ solid polymer electrolyte films,dispersed with Al<Subscript>2</Subscript>O<Subscript>3</Subscript> filler,for applications in sodium ion cells

The studies on solid polymer electrolyte (SPE) films with high ionic conductivity suitable for the realization of all solid-state Na-ion cells? form the focal theme of the work presented in this paper. The SPE films are obtained by the solution casting technique using the blend solution of poly (ethylene oxide) (PEO) with ethylene carbonate (EC) and propylene carbonate (PC) and complexed with sodium nitrate. Structural and thermal studies of SPE films are done by XRD, FTIR spectroscopy, and TGA techniques. Surface morphology of the films is studied using the FESEM. The ionic conductivity of SPE films is determined from the electrochemical impedance spectroscopy studies. For the SPE film with 16 wt% of NaNO₃ used for reacting with the polymer blend of PEO with EC and PC, the ionic conductivity obtained is around 1.08 × 10^?5 S cm^?1. Addition of the Al₂O₃ as the filler material is found to enhance the ionic conductivity of the SPE films. The studies on the Al₂O₃ modified SPE film show an ionic conductivity of 1.86 × 10^–4 S cm^?1, which is one order higher than that of the SPE films without the filler content. For the SPE film dispersed with 8 wt% of Al₂O₃, the total ion transport number observed is around 0.9895, which is quite impressive from the perspective of the applications in electrochemical energy storage devices. From the cyclic voltammetry studies, a wide electrochemical stability window up to 4 V is observed, which further emphasizes the commendable electrochemical behavior of these SPE films.     

Preparation and characterization of biodegradable poly(ε-caprolactone)-based gel polymer electrolyte films

Biodegradable polymer electrolyte films based on poly(ε-caprolactone) (PCL) in conjunction with lithium tetrafluoroborate (LiBF₄) salt and 1-ethyl-3-methylimidazolium tetrafluoroborate (EMIMBF₄) ionic liquid were prepared by solution cast technique. The structural, morphological, thermal, and electrical properties of these films were examined using X-ray diffraction (XRD), optical microscopy (OM), differential scanning calorimetry (DSC), and impedance spectroscopy. The XRD and OM results reveal that the pure PCL possesses a semi-crystalline nature and its degree of crystallinity decreases with the addition of LiBF₄ salt and EMIMBF₄ ionic liquid. DSC analysis indicates that the melting temperature and enthalpy are apparently lower for the 40 wt% EMIMBF₄ gel polymer electrolyte as compared with the others. The ambient temperature electrical conductivity increases with increasing EMIMBF₄ concentration and reaches a high value of ～2.83?×?10^?4 S cm^?1 for the 85 PCL:15 LiBF₄ + 40 wt% EMIMBF₄ gel polymer electrolyte. The dielectric constant and ionic conductivity follow the same trend with increasing EMIMBF₄ concentration. The dominant conducting species in the 40 wt% EMIMBF₄ gel polymer electrolyte determined by Wagner’s polarization technique are ions. The ionic conductivity of this polymer electrolyte (～2.83?×?10^?4 S cm^?1) should be high enough for practical applications.     

Effect of deposition time on structural and physical properties of Cu<Subscript>2</Subscript>CdSnS<Subscript>4</Subscript> thin films prepared by spray pyrolysis technique: experimental and ab initio study

Cu₂CdSnS₄ (CCdTS) thin films were synthesized using chemical spray pyrolysis deposition technique. The effect of various deposition times (20, 40, 60 min) on growth of these films was investigated. The as-synthesized Cu₂CdSnS₄ thin films were characterized by X-ray diffraction (XRD), ultraviolet–visible (UV–Vis) spectroscopy, Raman spectroscopy and Hall Effect measurements. The XRD pattern of Cu₂CdSnS₄ structured in stannite phase with preferential orientations along (112) planes. Raman spectrum revealed very strong peak at about 333 cm^?1. The films have the direct optical band gaps of 1.39–1.5 eV. The optimum hole mobility was found to be 3.212 × 10¹ cm² v^?1 s^?1 for the film deposited on 60 min. The electronic structure and optical properties of the stannite structure Cu₂CdSnS₄ were obtained by ab initio calculations using the Korringa–Kohn–Rostoker method combined with the Coherent Potential Approximation (CPA), as well as CPA confirms our results.     

Chemical bath deposition of SnO2 and Cd2SnO4 thin films

A new approach of chemical bath deposition (CBD) of SnO₂ thin films is reported. Films with a 0.2 μm thickness are obtained using the multi-dip deposition approach with a deposition time as little as 8–10 min for each dip. The possibility of fabricating a transparent conducting oxide layer of Cd₂SnO₄ thin films using CBD is investigated through successive layer deposition of CBD-SnO₂ and CBD-CdO films, followed by annealing at different temperatures. High quality films with transmittance exceeding 80% in the visible region are obtained. Annealed CBD-SnO₂ films are orthorhombic, highly stoichiometric, strongly adhesive, and transparent with an optical band gap of ～4.42 eV. Cd₂SnO₄ films with a band gap as high as 3.08 eV; a carrier density as high as 1.7 × 10²⁰ cm^?3; and a resistivity as low as 1.01 × 10^?2 Ω cm are achieved.     

Electrical properties of Sb-doped epitaxial SnO2 thin films prepared using excimer-laser-assisted metal–organic deposition

Excimer-laser-assisted metal–organic deposition (ELAMOD) was used to prepare Sb-doped epitaxial (001) SnO₂ thin films on (001) TiO₂ substrates at room temperature. The effects of laser fluence, the number of shots with the laser, and Sb content on the electrical properties such as resistivity, carrier concentration, and carrier mobility of the films were investigated. The resistivity of the Sb-doped epitaxial (001) SnO₂ thin film prepared using an ArF laser was lower than that of the film prepared using a KrF laser. The van der Pauw method was used to measure the resistivity, carrier concentration, and carrier mobility of the Sb-doped epitaxial (001) SnO₂ thin films in order to determine the effect of Sb content on the electrical resistivity of the films. The lowest resistivity obtained for the Sb-doped epitaxial (001) SnO₂ thin films prepared using ELAMOD with the ArF laser and 2 % Sb content was 2.5 × 10^?3 Ω cm. The difference between the optimal Sb concentrations and resistivities of the films produced using either ELAMOD or conventional thermal MOD was discussed.     

Structural,optical and electrical properties of tin oxide thin films by electrostatic spray deposition

Tin oxide (SnO₂) thin films were deposited by electrostatic spray deposition (ESD). The structural, optical and electrical properties of the films for different solvents were studied. The morphology of the deposited thin films was investigated by scanning electron microscopy. The optical transmission spectra of the films showed 66–75% transmittance in the visible region of spectrum. The electrical resistivity of thin films deposited using the different solvents ranged 1.08 × 10^?3–1.34 × 10^?3 Ω-cm. Overall, EG and PG were good solvents for depositing SnO₂ thin films by the ESD technique with stable cone jet.     

Improving the electrical conductivity of CuCrO2 thin film by N doping

N-doped CuCrO₂ thin films were prepared by using radio frequency magnetron sputtering technique. The XRD and XPS measurements were used to confirm the existence of the N acceptors in CuCrO₂ thin films. Hall measurements show the p-type conduction for all films. The electrical conductivity increases rapidly with the increase in N doping concentration, and the maximum of the electrical conductivity of 17 S cm⁻¹ is achieved for the film deposited with 30 vol.% N₂O, which is about three orders of magnitude higher than that of the undoped CuCrO₂ thin film. Upon increasing the doping concentrations the band gaps of N-doped CuCrO₂ thin films increase due to the Burstein-Moss shift.