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Herein, vertically aligned Al:WO 3 nanoplate arrays were directly grown on ITO glass by a facile electrodeposition method and annealed in an argon atmosphere at 450 °C for 2h. Besides, this study reports the influence of Al doping on the electrochromic properties of WO 3 film in detail. Electrochromic properties such as cyclic voltammetry, chronoamperometry and optical transmittance were analyzed by protonic insertion/extraction in the 1 M LiClO 4 /propylene carbonate as an electrolyte. The noticeable reversible color changing from transparent to the blue can be realized under the potential bias of ±1.0 V. XRD studies show that the produces films have highly crystalline structure. The EDS results clearly confirm the incorporation of Al element into the WO 3 network. From the optical absorption measurement, direct band gap energies are calculated as 3.62 and 3.34 eV for the WO 3 and the Al:WO 3 , respectively. Compared to the as-prepared WO 3 , the Al:WO 3 film exhibits outstanding electrochromic performance, including wide optical modulation (55.9%), high coloration efficiency (148.1 cm2C-1), quick reaction kinetics (1.23 s and 1.01 s for colored and bleaching times, respectively), good rate capability and cycle durability at a wavelength of 632.8 nm. EIS measurements based on a charge-transfer resistance reveal that the dramatic improvement in the electrochemically active surface is achieved in the Al:WO 3 film. The increase of active surface facilitates transport kinetics for electron and ion intercalation/deintercalation within the porous metal oxide to enhance coloration efficiency. Comparatively energy levels of the WO 3 and the Al:WO 3 electrochromic films are also represented. From the Mott-Schottky studies, it is estimated that the donor concentration of the films is of the order of 1020 cm−3. Taken together, these results not only provide important insight into a promising electrode for electrochromic displays applications, but also offer an economic and effective strategy for manufacturing of other doped metal oxide films. [ABSTRACT FROM AUTHOR]

In this research, transparent conductive films of indium tin oxide (ITO) were deposited by solution processing sol–gel ink through spin coating on soda-lime glass and sheet glass substrates. The processing parameters evaluated include the deposition humidity, spin coating speed, and ink concentration. The optical transmittance of the ITO thin films was collected by UV–vis spectrophotometry, while the electrical properties were studied by sheet resistance measurements and impedance spectroscopy (IS) using an in-plane configuration. The lowest sheet resistance achieved for a single layer film is 104 Ω/□, with a corresponding low frequency impedance magnitude of 2 × 105. These values were obtained at medium humidity values while maintaining high optical transparency (>90%) in the visible light region. High humidity values were found to affect the substrate wetting property of the ITO ink and increased the possibility of hydrolysis during deposition, resulting in the formation of non-uniform surface patterns. A spin coating speed of 4000 rpm or more is required to obtain a uniform ITO film with desirable electrical and optical properties. Once the optimum combination of parameters is obtained, the sheet resistance and impedance magnitude can be reduced to ∼102 Ω/□ through multilayer deposition and annealing in a reducing atmosphere with minimal effect on the optical transmittance (>90%) and surface morphology, making these materials useful as electrodes for electro-optic applications. When the optimal values of the main deposition parameters are used, the ink concentration was found to have minimal effect on the quality and properties of the ITO films. [ABSTRACT FROM AUTHOR]

The averaged power conversion efficiency of polyelectrolytes (P3CT-Na) based MAPbI3 solar cells can be increased from 14.94% to 17.46% with a wetting method before the spin-coating process of MAPbI3 precursor solutions. The effects of the wetting process on the surface, structural, optical and excitonic properties of MAPbI3 thin films are investigated by using the atomic-force microscopic images, x-ray diffraction patterns, transmittance spectra, photoluminescence spectra and Raman scattering spectra. The experimental results show that the wetting process of MAPbI3 precursor solution on top of the P3CT-Na/ITO/glass substrate can be used to manipulate the molecular packing structure of the P3CT-Na thin film, which determines the formation of MAPbI3 thin films. [ABSTRACT FROM AUTHOR]

Synthesis of antimony chalcogenides, especially Sb 2 S 3 , by facile and area scalable in-air chemical methods, such as spray pyrolysis, from cost-effective chemicals is certain to accelerate development of the related thin film solar cell technology. In this study, antimony ethyl xanthate, a scarcely studied halogenide-free precursor, is proven to be suitable for the deposition of conformal phase pure crystalline Sb 2 S 3 thin films via ultrasonic spray pyrolysis in air by a two-step process. First, a solution of antimony ethyl xanthate with thiourea in a molar ratio of 1/3, or with thioacetamide in a molar ratio of 1/10 was sprayed onto a glass/ITO/TiO 2 substrate by ultrasonic spray pyrolysis at 215°C to yield amorphous phase pure Sb 2 S 3 thin films. Second, performing post-growth heat treatment in vacuum at 225°C, was the key to produce phase pure conformal thin films of crystalline Sb 2 S 3 (E g 1.8 eV) with S/Sb atomic ratio of 1.46 by using thiourea, and 1.41 by using thioacetamide, respectively. Spraying solutions of antimony ethyl xanthate at ≥135°C resulted in the formation of the Sb 2 O 3 phase. Adding thiourea or thioacetamide to the spray solution prevented the oxidation of the growing Sb 2 S 3 layer during deposition at 135°C, 165°C, and 215°C. The suppressed oxidation of Sb 2 S 3 layers is attributed to the liquid state of thiourea and thioacetamide in these conditions. [Display omitted] • Spraying antimony ethyl xanthate without thioamide yields impure porous layers. • Thioamides suppress oxidation of Sb 2 S 3 layers sprayed from antimony ethyl xanthate. • Optimized deposition temperature and thioamide yields phase pure Sb 2 S 3 thin films. • Deposition temperature of 215°C is a prerequisite for uniform conformal thin films. [ABSTRACT FROM AUTHOR]

• Successful preparation of Zn:NiO films by safe and low-cost sol-gel spin coating method. • Compensation of singly and negatively charged Ni2+ ion vacancy by a positively charged hole. • Presence of hexagonal wurzite ZnO confirms formation of non-stoichiometric nickel oxide [Zn x Ni 1−x O]. • Higher concentration of holes leading to higher performance of p-type semi-conducting NiO as hole transporting material. • Abrupt and rare morphological, optical and electrical behaviors at certain heavy doping of transition metal Zn2+ Heavily Zinc ion (Zn2+)-doped nickel oxide (NiO) thin films had been prepared for the study of structural, optical and electrical properties in comparison with lower dopant concentration. Thin films were prepared through deposition on ITO coated glass substrate by using sol-gel spin coating technique. X-ray diffraction (XRD) patterns revealed the fact that Zn doped NiO (Zn:NiO) thin films are cubic in nature with two major diffraction peaks along (200) and (111) planes of cubic NiO phase. X-ray photoelectron Spectroscopy (XPS) data supported successful substitution of Zn2+ in NiO lattice. In, UV-Visible absorbance spectra the intensity maxima of the peaks was decreased with increase in doping concentration of Zn from 0% to 0.5–4.0%. The change in surface roughness of the Zn:NiO with varying dopant Zn2+ concentration was studied by Atomic Force Microscopy (AFM). Porus surface morphologies of the materials were evaluated in Field Emission Scanning Electron Microscopy (FESEM). The resistance change in both pure and Zn:NiO thin films was monitored by Electrochemical Impedance Spectroscopy (EIS) analysis. [ABSTRACT FROM AUTHOR]

• A boehmite layer was fabricated at low temperature by one-step solution method. • An all inorganic and all transparent ITO/boehmite/ITO stacked structure was fabricated for flexible memristor. • The device showed satisfied electrical characteristics and mechanical properties. • This work finds a new way to develop flexible memory devices and wearable electronics. In this work, an ITO/boehmite layer/ITO-stacked structure was fabricated at low temperature for transparent flexible memristor. Typical and reproducible bipolar switching behavior was easily obtained under applied bias. The resistive switching behaviors with satisfied electrical reliability such as retention, endurance and mechanical characteristics were all exhibited at different bending angles. The switching mechanism was considered to be related to the movement of H+ in boehmite layer. This low temperature processed, all inorganic and transparent flexible device provides a feasible way to develop new type of information devices and wearable electronics. [ABSTRACT FROM AUTHOR]

• Indium tin oxide (ITO) based multilayer films on p-silicon substrate were prepared. • 9 nm Cu and 6 nm Al metals interlayer inserted between two 37 nm ITO layers. • Sheet resistance of 3.26 Ω/sq, high figure of merit of 92.47 × 10−3 Ω−1 achieved at 600 °C. • Excellent rectifying contact with 0.71 eV barrier height obtained at 600 °C. The distinguished transparent conductive indium tin oxide (ITO) based multilayer films with thin copper-aluminium (Cu-Al) metals interlayer (ITO/Cu-Al/ITO) were prepared on p-type silicon (Si) by radio frequency and direct current magnetron sputtering methods. The ITO/Cu-Al/ITO (ICAI) films structural, topological, optical and electrical properties coupled with electronic properties of ICAI/p-type Si interface were investigated at different post annealing temperature up to 600 °C. Despite the inclusion of Cu-Al metals interlayer, structural analysis results yielded an amorphous structure for the as-deposited films. The films become polycrystalline with a cubic bixbyite structure after post annealing treatment. Dominant In 2 O 3 (222) and Cu (111) peaks intensities were observed at 500 °C and 600 °C indicating substantial enhancement in the films crystallinity at high moderate temperatures. The ICAI films reveal a smooth surface roughness with improved growth in grain size after post annealing treatment as examined by microscopic equipment.The films optical transmittance promptly increased from 73.2% (for as deposited film) to 88.7% (for annealed film at 600 °C) at 470 nm in the visible region with increasing post annealing temperature. The film annealed at 600 °C exhibits excellent electrical characteristics with a very low electrical resistivity of 2.44 × 10−5 Ω cm and sheet resistance of 3.26 Ω/sq. The ICAI films optoelectronic properties as calculated by figure of merit (FOM) show outstanding performance at 600 °C with a high FOM of 92.47 × 10−3 Ω−1 in spite of the reduced ITO films thickness. In addition, admirable ICAI/p-type Si interface quality was observed after post annealing treatment (at 600 °C) as indicated by current-voltage characteristics results. These improved ICAI multilayer films can be favourable for silicon heterojunction solar cells and other low resistance optoelectronic applications. [ABSTRACT FROM AUTHOR]

[Display omitted] • ITO surface modified with PEM@SiO 2 is examined for the first time. • The PEM was built using two oppositely charged polyelectrolytes. • PEM@SiO 2 exhibits charge sieving properties (studied with three redox probes). • Redox currents depend on the charge of the polyelectrolyte terminating PEM. • Electrochemical, XPS, FTIR-ATR and SEM characterizations were performed. Simple modification techniques affecting surface properties in a switchable manner are key to the development of smart materials. Layer-by-layer assembly of oppositely charged polyelectrolytes (poly(diallyldimethylammonium chloride) and (poly(styrene sulfonate)) over an electrode modified with a mesoporous silica thin film makes a platform with alternating amplification and sieving electrochemical properties defined by the terminating polyelectrolyte layer. The mesoporous silica thin films were formed via sol–gel processing in the presence of a soft template (Electrochemically Assisted Self-Assembly). The electrochemical properties of the designed platforms were studied in the presence of positively charged (Ru(NH 3) 6 3+), neutral (FcMeOH), and negatively charged (Fe(CN) 6 4-) redox probes. Additionally, we provide proof-of-concept studies in which our platforms are applied to the electroanalytical screening of ascorbic acid and dopamine. [ABSTRACT FROM AUTHOR]

In this paper, we numerically study the Bulk Heterojunction (BHJ) inverted organic solar cells (OSCs) of ITO/ETL/POLYMER:PCBM/HTL/Ag using the effective medium model (EMM) with SCAPS-1D potential numerical tool. This model contributes to the charge transport processes understanding. We investigate the influence of two elements: the polymer material of the active layer poly(3-hexylthiophene) (P3HT)/polythieno[3,4-b]-thiophene-co-benzodithiophene (PTB7), and the anodic interfacial film (HTL) Poly (3,4-ethylene dioxythiophene):poly (styrenesulfonate) (PEDOT:PSS)/molybdenum trioxide (MoO 3) on the electrical and optical performance of the devices: open circuit voltage (Voc), short circuit current (Jsc), fill factor (FF) power conversion efficiency (PCE), and the external quantum efficiency (EQE). Our results indicate an efficiency improvement (PCE) of 5.73% for the PTB7 solar cell compared to the P3HT of 4.88%. Also, the PCE of the device increases further to 5.92% with the modification of the anodic thin film PEDOT:PSS by MoO 3. The simulated results show a good agreement with the results published in theory. [Display omitted] • The Properties of bulk heterojunction inverted organic solar cells have been studied by the SCAPS-1D simulator. • Modification of the conjugated polymer from the active layer. • Variation of the anodic interfacial layer material. • The aim is to ameliorate the power conversion efficiency. [ABSTRACT FROM AUTHOR]

Amorphous aluminum-doped indium tin oxide (ITO) thin films with a reduced indium oxide content of 50 mass% were manufactured by co-sputtering of ITO and Al2O3 targets in a mixed argon–oxygen atmosphere onto glass substrates preheated at 523 K. The oxygen gas flow rate and heat treatment temperature effects on the electrical, optical and structural properties of the films were studied. Thin films were characterized by means of a four-point probe, ultraviolet–visible-infrared (UV–Vis-IR) spectroscopy and X-ray diffraction. Transmittance of films and crystallization temperature increased as a result of doping of the ITO thin films by aluminum. The increase in oxygen flow rate led to an increase in transmittance and hindering of the crystallization of the aluminum-doped indium saving ITO thin films. It has been found that the film sputtered under optimal conditions showed a volume resistivity of 713 µΩ cm, mobility of 30.8 cm2/V·s, carrier concentration of 2.9 × 1020 cm−3 and transmittance of over 90% in the visible range. [ABSTRACT FROM AUTHOR]

We proposed the enhancement of the electrical properties of solution-processed indium–tin–oxide (ITO) thin films through microwave irradiation (MWI) and argon (Ar) gas plasma treatment. A cost- and time-effective heat treatment through MWI was applied as a post-deposition annealing (PDA) process to spin-coated ITO thin films. Subsequently, the sheet resistance of MWI ITO thin films was evaluated before and after plasma treatment. The change in the sheet resistance demonstrated that MWI PDA and Ar plasma treatment significantly improved the electrical properties of the ITO thin films. Furthermore, X-ray photoelectron spectroscopy and X-ray diffraction analyses showed that the electrical properties of the ITO thin films were enhanced by the increase in oxygen vacancies due to the ion bombardment effect of high-energy plasma ions during Ar plasma treatment. Changes in the band gap structure of the ITO thin film due to the ion bombardment effect were also analyzed. The combination of MWI PDA and Ar plasma treatment presents new possibilities for improving the high-conductivity sol–gel ITO electrode. [ABSTRACT FROM AUTHOR]