Stable Tin Chloride Perovskite Sensitized Silver Doped Titania Nanosticks Photoanode Solar Cells with Different Hole Transport Materials

Perovskite sensitized solar cells (PSSCs) have recently been catapulted to the cutting edge of thin-film photovoltaic research and development because of their promise for higher power conversion efficiencies and ease of fabrication. In this work, an attempt has been made to fabricate CH₃NH₃SnCl₃ perovskite sensitized silver doped titania nanosticks photoanode solar cells with an efficient hole transport material (HTM), spiro-MeOTAD, poly(3-hexylthiophene-2,5-diyl) (PTTA) and CuI and attained light to electricity power conversion efficiency (PCE) of 10.46, 7.89 and 6.05 % respectively, under AM 1.5G illumination of 100 mW/cm² intensity. As well, PSSCs made with redox couple electrolytes namely quasi-solid state electrolyte (QSSE) and ionic liquid (IL) electrolyte exhibited the PCE of 4.92 and 3.20 % respectively. A metal oxide (HfO₂) layer is coated on the perovskite sensitized photoanode, which could increase the stability of PSSCs. The current density (Jsc)–open circuit voltage (Voc) study shows that PSSCs made with HTMs exhibited better fill factor and PCE. The electron impedance spectroscopy revealed that the electron lifetime (τ_n), electron mobility (µ) and charge collection efficiency (η_cc)in the PSSCs are in the order spiro-MeOTAD > PTTA > CuI > QSSE > IL. This work expresses that the nature of the HTM is essential for charge recombination and elucidates that finding an optimal HTM for the perovskite solar cell includes controlling the perovskite/HTM interaction.     

A thioacetamide interlayer anchoring TiO2 and (FAPbI3)1−x(MAPbBr3)x for high-performance perovskite solar cells

In the perovskite solar cells (PSCs), traps of the perovskite film or interface are the research focus, which can severely hinder charge transfer and benefit charge recombination, thus weakening the photoelectric performance of the devices. Herein, a Thioacetamide (TAA) interfacial layer is used to passivate the traps of PSCs. Comparing to the control device (17.65%), the TAA-based solar cells can achieve an enhanced efficiency of 19.14%. It is found that the passivation caused by TAA occurs through the interactions of sulfur in TAA with undersaturated Pb in perovskite and Ti⁴⁺ in TiO₂, resulting in a faster and more efficient charge transfer and a greatly reduced trap density from 3.36 × 10¹⁶ cm⁻³ to 1.93 × 10¹⁶ cm⁻³. It is shown that the modification method using TAA may be helpful for passivating traps and obtaining excellent photoelectric properties of PSCs.     

Lead free CsSn0.5Ge0.5I3 perovskite solar cell with different layer properties via SCAPS-1D simulation

Organic–inorganic halide perovskite solar cells (PSCs) have been extensively studied due to their simple fabrication methods and obvious device efficiency advantages. In this work, the perovskite CsSn_0.5Ge_0.5I₃ is used as the light absorption layer, which is doped with Ge²⁺ in CsSnI₃ to improve its stability. The polymers of 3-hexylthiophene (P3HT) with excellent optoelectronic properties and low price, and SnO₂ with high electron extraction ability is selected as charge transport layers. Based on these, a novel PSC structure (FTO/SnO₂/IDL1/CsSn_0.5Ge_0.5I₃/IDL2/P3HT/Au) has been simulated via solar cell capacitor simulator (SCAPS-1D). The PSC performance is optimized by adjusting a series of parameters, including the layer thickness, defect density, electron affinity potential energy, and operating temperature, and so forth. The results show that the PSC defects are passivated by adjusting the appropriate parameters, and the final optimized open circuit voltage (V_OC) is 1.08 V, short-circuit current density (J_SC) is 27.37 mA/cm², fill factor (FF) is 83.32%, while the power conversion efficiency (PCE) is increased from the initial 10.89% to 24.63%, which provides theoretical reference for experiments and new ideas for the preparation and development of efficient and environmentally friendly PSCs. Finally, the effect of different metal cathodes with and without hole transport layer (HTL) on PSC performance is compared. The PSCs without HTL are more dependent on battery cathodes, which provided a way to replace precious metals with other electrode materials.     

Polyaniline polymer-modified ZnO electron transport material for high-performance planar perovskite solar cells

In this study, an efficient strategy is used to prepare perovskite photoactive layer with superb optoelectronic merits by utilizing polyaniline polymer as an efficient additive to improve perovskite quality. As a result, we prove that the small content of polyaniline (PANI) provides not only suppresses the perovskite defects and lead iodide but also produces a passivation impact. By regarding using macromolecular phases with long chain polymers, the generation of a PANI-perovskite cross-linking is possible. The cross-linking acts to bridge the perovskite crystals, mitigating carrier trapping by grain boundaries and achieving remarkable air stability against humid, which has not been obtainable with tiny molecules defect passivating materials. Also, PANI promoted the development of Lewis base adduct with the perovskite precursor, which, maximized the activation energy for nucleation and growth of the perovskite phase. Therefore, the perovskite layer with optimized PANI additive showed higher crystallinity in (110) crystal plane. After PANI addition, the perovskite grains found to be enlarged from 350 nm to 620 nm. Also, the PSCs with PANI showed suppressed luminescence effect, which indicates lower recombination rates. The SCLC measurements revealed that the PANI additive improving the interfacial contact between the ZnO and perovskite due to reduction the trapped density from 1.78 × 10¹⁶ cm^-3 to 2.46 × 10¹⁵. Consequently, the champion cell yields an efficiency of 17.39% for 4% polyaniline doped electron transport material with negligible hysteresis. This reduces PSC instability generating a device that retained 93% of its original performance after 600 h maintaining in air conditions without any encapsulation.     

Vacuum-deposited perovskite CsPbBr3 thin-films for temperature-stable Si based pure-green all-inorganic light-emitting diodes

Metal halide perovskite light-emitting diodes (PeLEDs) are excellent candidates in the field of lighting and display due to their outstanding optical-electrical properties. However, the solution-processed technology of perovskite films and the organic electron/hole transport layers of PeLEDs make it still challenging to improve the operational stability of devices. Herein, we successfully prepared highly luminescent CsPbBr₃ perovskite films via vacuum-deposited method and then fabricated all-inorganic PeLEDs with the heterostructure of p-NiO/CsPbBr₃/n-Si. Our device exhibits pure-green emission with a wavelength of 527 nm, a narrow full width at half-maximum of 18 nm, and a maximum luminance of 51933 cd/m², representing one of the best brightness pure-green PeLEDs. Most importantly, the PeLEDs exhibited great thermal stability with a heat resistance up to 80 °C. The electroluminescence peak position of the PeLEDs remains consistent when the ambient temperature increases from 40 °C to 110 °C. Moreover, the all-inorganic PeLEDs can maintain their good luminescence performance after seven thermal cycling tests (30 °C–100 °C). This work not only demonstrated a facile strategy to prepare high-quality pure-green CsPbBr₃ perovskite films, but also provided an important all-inorganic device structure for high thermal stability of PeLED.     

Nanostructured bilayer CuSCN@CuI thin films as efficient inorganic hole transport material for inverted perovskite solar cells

In this work, the development of bilayer CuSCN@CuI inorganic hole transport material by a simple electrochemical approach is demonstrated. The thickness and the morphology of the bilayer thin films are controlled by electrochemical potential and deposition time. Uniformly distributed triangle-shaped CuI nanosheets formation is observed at 2 min deposition time. Inverted perovskite solar cells are fabricated using electrochemically grown CuSCN@CuI bilayer and tested its photovoltaic performance. The maximum short circuit current density of 18.24 mA/cm² and open-circuit voltage of 1080 mV is achieved for uniformly distributed triangle-shaped CuI nanosheets grown at 2 min deposition time. The power conversion efficiency (PCE) of 15.58% is achieved with 1400 h of stability. The moderate thickness (~180–230 nm) of bilayer CuSCN@CuI nanostructures showed better charge transport and photovoltaic performance. The favourable band alignment of the designed CuSCN@CuI/perovskite/PC₆₁BM/Carbon delivers stable open-circuit voltage than the earlier reports. The optimized bilayer CuSCN@CuI nanostructure with carbon back contact showed improved device stability.     

Encapsulating homogenous ultra-fine SnO2/TiO2 particles into carbon nanofibers through electrospinning as high-performance anodes for lithium-ion batteries

Homogenous ultra-fine SnO₂/TiO₂ particles encapsulated into carbon nanofibers (SnO₂/TiO₂@CNFs) with a uniform and ordered one-dimensional fibrous structure are fabricated through facile electrospinning technique and subsequent heat treatments, which are confirmed by XRD, Raman, TG, SEM, TEM, and XPS analyses. The battery performance reveals that the SnO₂/TiO₂@CNFs-1.5:1 (1.5:1 denotes the mole ratio of SnO₂ to TiO₂ in the carbon nanofibers) electrode displays the optimal electrochemical properties among the whole samples, which can deliver the initial charge and discharge specific capacity of 1061.2 and 1494.8 mAh/g with a coulombic efficiency of 71.0% at 100 mA/g, and exhibit a remarkable specific capacity of 766.1 mAh/g after 200 cycles. Moreover, the SnO₂/TiO₂@CNFs-1.5:1 electrode displays a high pseudocapacitive contribution of 73.9% at the scan rate of 2 mV/s and the lithium ion diffusion coefficient of approximately 1.20 × 10^?15 cm² s^?1. The excellent electrochemical performance of the SnO₂/TiO₂@CNFs-1.5:1 electrode is closely correlated with the synergetic effect of the proper amount of TiO₂ that enhances the electrochemical stability of the electrode and provides fractional capacity, and the flexible and conductive carbon nanofiber matrix that accommodates volume changes and increases overall electronic conductivity. The detailed investigations of the as-prepared electrode materials by a facile electrospinning process may pave possible instructions for the next generation SnO₂-based anodes and other related electrospun anodes for the energy storage device.     

Optimization of TiO2 paste concentration employed as electron transport layers in fully ambient air processed perovskite solar cells with a low-cost architecture

The optimization of thickness and surface roughness of the TiO₂ layer as an efficient electron transporting layer (ETL) plays a significant role on the performance improvement of perovskite solar cells (PSCs). In the present investigation, TiO₂ pastes synthesized with various concentrations under hydrothermal conditions were utilized to deposit the TiO₂ films of tunable porosities as the ETLs of PSCs. Also, the PSCs were fabricated with a structure of FTO/block-TiO₂ (b-TiO₂)/m-TiO₂/CH₃NH₃PbI₃ (MAPbI₃)/CuInS₂ (CIS)/carbon as a low-cost architecture. Moreover, the effect of the TiO₂ paste concentration was studied on the performances of PSCs under fully ambient conditions. The optimal TiO₂ layer was constructed with 20 wt% TiO₂ paste concentration, which resulted in the formation of a hole‐free, smooth, and compact ETL layer. The champion perovskite solar cell fabricated with the 20 wt% TiO₂ paste concentration showed the highest power conversion efficiency (PCE) of 13.09% (J_SC = 20.80 mA cm^?2, V_OC = 0.98 V and FF = 0.64) but the champion PSC device made with the 10 wt% TiO₂ paste exhibited the lowest PCE = 8.05% (J_SC = 19.83 mA cm^?2, V_OC = 0.91 V and FF = 0.45). These results illustrated that the optimal 20 wt% TiO₂ paste caused ～163% enhancement in the PCE of the device. Consequently, it could be suggested for application in fabrication of cost-effective and large scale PSCs.     

Enhanced luminescence properties and device applications of Tb3+-doped Cs4PbBr6 perovskite quantum dot glass

Cs₄PbBr₆ perovskite quantum dots (QDs) have unique optoelectronic properties and are expected to become a new generation of luminescent materials. However, poor stability, low photoluminescence quantum yield (PLQY), and poor understanding as to the origin of photoluminescence behavior limit its further application. In this study, a series of Tb³⁺-doped Cs₄PbBr₆ perovskite QD glasses with excellent stability were obtained through the optimization of Tb³⁺ doping concentration and in-situ crystallization temperature. Density functional theory calculations and experimental characterization showed that an appropriate amount of lattice-incorporated Tb³⁺ ions can reduce structural defects in QDs, improve the PLQY, and reduce the QD heavy-metal requirements. Notably, the maximum PLQY value reached 47%, which is near to the Cs₄PbBr₆ perovskite crystal. Furthermore, a high-performance white light-emitting diode (WLED) device was prepared. The device featured a color rendering index of 80 and luminous efficiency of 41 lm W^?1. Finally, a QD glass with double emission peaks was prepared by controlling the in-situ crystallization temperature (550 °C). The temperature sensitivity of the QD glass was then studied using the fluorescence intensity ratio method. The maximum relative temperature sensitivity (Sr) reached 2.03% K^?1, which is higher than the previously reported value. Thus, the method proposed in this study can greatly improve the photoluminescence properties of Cs₄PbBr₆ QD glass and expand its applications in WLED and visual temperature sensing.     

Exploring the influence of Zn2SnO4/ZIF-8 nanocomposite photoelectrodes on boosting efficiency of dye sensitized solar cells

It is imperative to develop innovative efficient photoelectrode materials for high-performance dye-sensitized solar cells (DSSCs). In this work, cubic spinel Zn₂SnO₄ (ZTO)+(5, 10, 15, 20%) zeolite imidazole framework-8 (ZIF-8) nanoparticles were applied as photoanode materials of DSSC devices. The Zn₂SnO₄ was effectively synthesized in a simple and cost-effective manner by carefully controlling the hydrothermal conditions. The Zn₂SnO₄/ZIF-8 nanocomposite photoelectrodes were coated over the TiO₂ compact layer to decrease charge recombination at the transparent conductive oxide/mesoporous interface. The X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), energy dispersive X-ray spectroscopy (EDS), diffuse reflectance spectroscopy (DRS), photoluminescence (PL), Brunauer–Emmett–Teller (BET) isotherms, Fourier transform infrared spectroscopy (FT-IR) and electrochemical impedance spectroscopy (EIS) analysis methods were used to study the properties of all nanostructured photoanodes. In addition, the effects of Zn₂SnO₄/ZIF-8 nanocomposites were evaluated on DSSCs performances. The results clearly showed that adding ZIF-8 to Zn₂SnO₄ improved the photovoltaic performance of the fabricated DSSCs. Furthermore, compared to pure Zn₂SnO₄ NPs, Zn₂SnO₄+15% ZIF-8 increased open circuit voltage (V_OC) from 0.64 to 0.77 V and short current density (J_SC) from 6.89 to 11.27 mA/cm². The Zn₂SnO₄+15% ZIF-8 photoanodes increased the power conversion efficiency (PCE) of DSSC by about 195% (from 2.02 to 3.94%) relative to the pure ZTO photoanode. This was due to the fact that the Zn₂SnO₄+15% ZIF-8 nanocomposite had the quickest electron transport rate, the best electron collecting efficiency, and the greatest charge recombination resistance, all of which are extremely advantageous to improve device efficiency.     

Oxygen vacancy luminescence and band gap narrowing driven by Ce ion doping with variable valence in SnO2 nanocrystals

Although considerable research works have witnessed the important modulations of oxygen vacancies on the optical, electrical, and magnetic properties of SnO₂ nanostructures, it is not easy to control oxygen vacancy defects in such systems.The difficulty stems from that oxygen vacancy is a kind of atomic defect, and its distribution is sensitive to process conditions and external factors, which makes direct characterization and purposeful control difficult. The purpose of this work on Ce-doped SnO₂ nanocrystals is to investigate the tolerance of the host lattice to Ce ions, the population and evolution of Ce³⁺/Ce⁴⁺ ions, and the possibility to adjust oxygen vacancies by Ce³⁺ ions, and then focus on the influence of oxygen vacancy defects on the band gap and luminescence performance. As Ce doping concentration increases from 0 to 12 at.%, the doped system changes from Ce³⁺ dominated at low doping amount (≤3 at.%) to Ce³⁺/Ce⁴⁺ coexistence at medium doping concentration (3 at.% ∼ 9 at.%), to occurrence of CeO₂ impurity phase at over doping (∼12 at.%). The optimum doping occurs at 6 at.%, which corresponds to the saturated critical point of Ce³⁺ content and the maximum oxygen vacancy concentration. Importantly, the oxygen vacancies in the current Ce-doped SnO₂ nanocrystals is directly regulated by the Ce³⁺ ion concentration on the Sn sites, which plays an important role in the band gap tuning and visible light emission. With Ce concentration increasing from 0 to 12 at.%, the band gap monotonicity decreases from 3.36 eV to 3.12 eV, while the intensity of the oxygen vacancy luminescence band first increases and then decreases, with the turning point at 6 at.%. Both band gap narrowing effect and enhanced emission indicate that Ce-doped SnO₂ should be a promising method to design and manufacture visible light responsive SnO₂ based optoelectronic materials by manipulating oxygen vacancy defects.     

Carbon coated porous tin peroxide/carbon composite electrode for lithium-ion batteries with excellent electrochemical properties

A porous tin peroxide/carbon (SnO₂/C) composite electrode coated with an amorphous carbon layer is prepared using a facile method. In this electrode, spherical graphite particles act as supporter of electrode framework, and the interspace among particles is filled with porous amorphous carbon derived from decomposition of polyvinylidene fluoride and polyacrylonitrile. SnO₂ nanoparticles are uniformly embedded in the porous amorphous carbon matrix. The pores in amorphous carbon matrix are able to buffer the huge volume expansion of SnO₂ during charge/discharge cycling, and the carbon framework can prevent the SnO₂ particles from pulverization and re-aggregation. The carbon coating layer on the outermost surface of electrode can further prevent porous SnO₂/C electrode from contacting with electrolyte directly. As a result, the repeated formation of solid electrolyte interface is avoided and the cycling stability of electrode is improved. The obtained SnO₂/C electrode presents an initial coulombic efficiency of 77.3% and a reversible capacity of 742 mA h g⁻¹ after 130 cycles at a current density of 100 mA g⁻¹. Furthermore, a reversible capacity of 679 mA h g⁻¹ is obtained at 1 A g⁻¹.     

Effects of hydrogen plasma treatment on the physical and chemical properties of tin oxide thin films for ambipolar thin-film transistor applications

In this study, we investigated the physical and chemical properties of H₂ plasma-treated tin oxide (SnO_X) thin films, followed by their applications in ambipolar thin-film transistors (TFTs). Finely controlled H₂ implantation was carried out using a reactive-ion-etching system at a radio frequency power of 30 W and under various exposure times. H₂ plasma treatments induced changes in the chemical structures and surface morphologies of the SnO_X thin films, including a partial phase transformation of Sn and SnO to SnO₂. The defects originating from oxygen vacancies (O_Vacs) in the SnO_X thin films were passivated by H via the formation of Sn–H bonds, which decreased the density of subgap states in the SnO_X thin films. The H₂ plasma-treated SnO_X TFTs showed considerably improved ambipolarity and electrical performance. Complementary metal–oxide–semiconductor (CMOS) logic inverters comprising H₂-plasma-treated ambipolar SnO_X TFTs exhibited a maximum gain of 34.5 V/V at a supply voltage of 10 V. The results of this study present the meaningful investigation of H₂ plasma-treated ambipolar SnO_X TFTs that can be used to fabricate CMOS circuits for various applications.     

Electric field-assisted flash sintering of tin dioxide

SnO₂ green pellets were submitted to ac electric fields at temperatures below 1350 °C. Electric current pulses occurred and a substantial modification was found in the microstructure of the pellets after application of 80 V cm⁻¹ at 900, 1100 and 1300 °C. Similar experiments were carried out in SnO₂ mixed to 2 wt.% MnO₂. The linear shrinkage of the pellets was monitored with a dilatometer during the application of the electric field. Scanning electron microscopy micrographs of the pellets show the grain structure evolution after the electric current pulses. The larger is the electric current flow through the SnO₂ pellet, the larger are the shrinkage and the average grain size. Even though sintering occurs without significant densification in SnO₂, the welding of the grains is evident. The apparent density of green pellets of SnO₂ with MnO₂ addition sintered at 1100 °C increased 110% with the application of 80 V cm⁻¹, 5 A.     

Highly conducting and transparent antimony doped tin oxide thin films: the role of sputtering power density

Sb doped SnO₂ thin films were deposited on quartz substrates by magnetron sputtering at 600 °C and the effects of sputtering power density on the preferential orientation, structural, surface morphological, optical and electrical properties had been studied. The XRD analyses confirm the formation of cassiterite tetragonal structure and the presence of preferential orientation in (2 1 1) direction for tin oxygen thin films. The dislocation density analyses reveal that the generated defects can be suppressed by the appropriate sputtering power density in the SnO₂ lattice. The studies of surface morphologies show that grain sizes and surface roughness are remarkably affected by the sputtering power density. The resistivity of Sb doped SnO₂ thin films gradually decreases as increasing the sputtering power density, reaches a minimum value of 8.23×10⁻⁴ Ω cm at 7.65/cm² and starts increasing thereafter. The possible mechanisms for the change in resistivity are proposed. The average transmittances are more than 83% in the visible region (380–780 nm) for all the thin films, the optical band gaps are above 4.1 eV. And the mechanisms of the variation of optical properties at different sputtering power densities are addressed.     

New catalytic system for oxidation of isopropyl alcohol with thin film catalysts

This paper describes a new catalytic system developed to study catalysts deposited as thin films on a metallic support. This device uses the electromagnetic induction for heating the metallic support. Therefore, it enables homogeneous sample heating, up to 400 °C·min^− 1 with a good regulation and a very low thermal inertia allowing fast cooling and accurate hold on temperature plateau. Catalysts SnO₂, 0.3 and 1 wt.% Pt on SnO₂ were deposited on stainless steel by an electrophoretic technique and evaluated in the abatement of isopropyl alcohol in air, a common model for VOCs.     

Electrospun ZnO–SnO2 composite nanofibers with enhanced electrochemical performance as lithium-ion anodes

ZnO–SnO₂ composite nanofibers with different structures were synthesized by a simple electrospinning approach with subsequent calcination at three different temperatures using polyacrylonitrile as the polymer precursor. The electrochemical performance of the composites for use as anode materials in lithium-ion batteries were investigated. It was found that the ZnO–SnO₂ composite nanofibers calcined at 700 °C showed excellent lithium storage properties in terms of cycling stability and rate capability, compared to those calcined at 800 and 900 °C, respectively. ZnO–SnO₂ composite nanofibers calcined at 700 °C not only delivered high initial discharge and charge capacities of 1450 and 1101 mAh g⁻¹, respectively, with a 75.9% coulombic efficiency, but also maintained a high reversible capacity of 560 mAh g⁻¹ at a current density of 0.1 A g⁻¹ after 100 cycles. Additionally, a high reversible capacity of 591 mAh g⁻¹ was obtained when the current density returned to 0.1 A g⁻¹ after 50 cycling at a high current density of 2 A g⁻¹. The superior electrochemical performance of ZnO–SnO₂ composite nanofibers can be attributed to the unique nanofibrous structure, the smaller particle size and smaller fiber diameter as well as the porous structure and synergistic effect between ZnO and SnO₂.     

Improved ethanediol sensing with single Yb ions doped SnO2 nanobelt

Yb-doped SnO₂ nanobelts (Yb–SnO₂ NBs) and pure SnO₂ nanobelts (SnO₂ NBs) are successfully synthesized by thermal evaporation method and their composition and morphology are characterized. The single nanobelt device is fabricated by dual-ion beam deposition system, and the gas sensing performance to ethanediol, methanal, ethanol and acetone is investigated. The results show that the best working temperature of single Yb–SnO₂ NB sensor to ethanediol is 190 °C, which is lower than that of pure counterpart and the highest sensitivity is 10.5 to 100 ppm of ethanediol. In addition, it is found that the response/recovery time is short and the sensor exhibits excellent selectivity and stability. The sensing performance of SnO₂ NB is actually improved by Yb.     

Magnetic Properties of Mn‐doped SnO2 Thin Films Prepared by the Sol–Gel Dip Coating Method for Dilute Magnetic Semiconductors

Manganese‐doped tin oxide (SnO₂:Mn) thin films were deposited on glass substrates by the sol–gel dip coating technique. The effect on structural, morphological, magnetic, electrical, and optical properties in the films with different Mn concentrations (0–5 mol%) were investigated. X‐ray diffraction patterns (XRD) showed the deterioration of crystallinity with increase in Mn‐doping concentration. Scanning electron microscopy (SEM) studies showed an inhibition of grain growth with an increase in Mn concentration. X ray photoelectron spectroscopy (XPS) revealed the presence of Sn⁴⁺ and Mn³⁺ in SnO₂: Mn films. SnO₂: Mn films show ferromagnetic and paramagnetic behavior. These SnO₂:Mn films acquire n‐type conductivity for 0–3 mol% (SnO₂ ‐ Sn_0.97Mn_0.03O_{2) ‐}doping concentration and p type for 5 mol% Mn‐doping concentration(Sn_0.95Mn_0.05O₂) in SnO₂ films. An average transmittance of > 75% (in UV‐Vis region) was observed for all the SnO₂:Mn films. Optical band gap energy of SnO₂: Mn films were found to vary in the range 3.55 to 3.71 eV with the increase in Mn‐doping concentration. Photoluminescence (PL) spectra of the films exhibited an increase in the emission intensity with increase in Mn‐doping concentration which may be due to structural defects or luminescent centers, such as nanocrystals and defects in the SnO₂. Such SnO₂:Mn films with structural, magnetic and optical properties can be used as dilute magnetic semiconductors.     

Structural, Electrical and Optical Properties of p-Type Transparent Conducting SnO2:Zn Film

Highly transparent, p-type conducting SnO₂:Zn films were deposited on quartz substrates by radio frequency (RF) magnetron sputtering using a 12 wt% ZnO doped with 88 wt% SnO₂ ceramic target followed by annealing at various temperatures. The effect of annealing temperature on the structural, electrical and optical performances of SnO₂:Zn films has been studied. XRD results show that all the SnO₂:Zn films possess tetragonal rutile structure with the preferred orientation of (101). Hall effect results indicate that at 873 K for 3 h was the optimum annealing parameters for p-type SnO₂:Zn films with relatively high hole concentration and low resistivity of 3.334 × 10¹⁹ cm⁻³ and 3.588 Ω cm, respectively. The average transmission of the p-type SnO₂:Zn films were above 80% in the visible light range. In addition, p-type conductivity was also confirmed by the non-linear characteristics of a p-type SnO₂:Zn/n-type SnO₂:Sb structure.