ITO Substrate Research Articles

Repairing Interfacial Defects in Self-Assembled Monolayers for High-Efficiency Perovskite Solar Cells and Organic Photovoltaics through the SAM@Pseudo-Planar Monolayer Strategy.

Lately, carbazole-based self-assembled monolayers (SAMs) are widely employed as effective hole-selective layers (HSLs) in inverted perovskite solar cells (PSCs). Nevertheless, these SAMs tend to aggregate in solvents due to their amphiphilic nature, hindering the formation of a monolayer on the ITO substrate and impeding effective passivation of deep defects in the perovskites. In this study, a series of new SAMs including DPA-B-PY, CBZ-B-PY, POZ-B-PY, POZ-PY, POZ-T-PY, and POZ-BT-PY are synthesized, which are employed as interfacial repairers and coated atop CNph SAM to form a robust CNph SAM@pseudo-planar monolayer as HSL in efficient inverted PSCs. The CNph SAM@pseudo-planar monolayer strategy enables a well-aligned interface with perovskites, synergistically promoting perovskite crystal growth, improving charge extraction/transport, and minimizing nonradiative interfacial recombination loss. As a result, the POZ-BT-PY-modified PSC realizes an impressively enhanced solar efficiency of up to 24.45% together with a fill factor of 82.63%. Furthermore, a wide bandgap PSC achieving over 19% efficiency. Upon treatment with the CNph SAM@pseudo-planar monolayer, also demonstrates a non-fullerene organic photovoltaics (OPVs) based on the PM6:BTP-eC9 blend, which achieves an efficiency of 17.07%. Importantly, these modified PSCs and OPVs all show remarkably improved stability under various testing conditions compared to their control counterparts.

Enhancing photovoltaic applications through precipitating agents in ITO/CIS/CeO2/Al heterojunction solar cell

In this groundbreaking study, we successfully synthesized both cerium oxide and copper indium sulphate nanoparticles via co-precipitation method and the same is spray coated on ITO substrate by Jet Nebulizer Spray Pyrolysis (JNSP) technique. A comprehensive characterization of the structural, morphological and Photo-diode properties was conducted using a range of advanced techniques. X-ray diffraction revealed a superior mono-crystalline cubic fluorite structure with a preferred orientation along the (111) plane, indicating exceptional crystal quality. Scanning electron microscopy and transmission electron microscopy images showed the formation of disk-shaped particles with sharp rounded edges, averaging ∼ 5 nm in size. Fourier transform infrared spectroscopy identified the phonon band envelope of the metal oxide (CeO2) network at 848 cm−1 while photoluminescence spectroscopy revealed blue and blue-green emission in the visible spectrum. Thermogravimetric-differential thermal analysis exhibited a total weight loss of 19.52 % with four distinct exothermic and endothermic peaks. X-ray photoelectron spectroscopy confirmed the presence of Ce and O elements, with a minor amount of carbon absorbed from the atmosphere and revealed the dominant occurrence of Ce4+ and minority occurrence of Ce3+. The maximum power conversion efficiency of 0.23 % was achieved for samples prepared using NH3 precipitant making them highly suitable for photovoltaic applications. This work paves the way for future research in optimizing cerium oxide nanoparticles for high-performance photovoltaic devices potentially leading to breakthroughs in renewable energy harvesting.

Investigation of zinc oxide doped microstructures with cobalt via electrochemical deposition

The present paper reports electrochemical elaboration of zinc oxide microstructure doped with cobalt (CZO) at various [Co2+]/[Zn2+] (Co/Zn) concentration ratios onto ITO substrates at a pH of 6.5. All Mott-Schottky plots of electrochemical analysis showed that all electrodeposited CZO samples exhibited n-type semiconducting behaviours. XRD spectra revealed that all electrodeposited CZO samples crystallized in the typical hexagonal wurtzite structure with a preferential orientation along the (100) plane with descending crystalline size versus increasing cobalt dopants amount. Reviewing SEM images, notable changes were found on granular morphologies of CZO samples because of doping changing. EDX showed proportionality between the increase of final Co/Zn ratio in the CZO samples and the increase of starting Co/Zn concentration ratio within the initial depositing solutions. UV–Vis measurements indicated that transmittances of most CZO samples were above 80 % in the visible range and their optical band gaps were high and limited between 3.60 and 3.64 eV.

Synthesis of tantalum oxide thin films using RF magnetron sputtering for RRAM application

Resistive Random Access Memory (RRAM) is a prominent contender in the realm of emerging non-volatile memory technologies owing to its numerous advantages like simple structure, low power usage, high speed, and exceptional scalability. In the current study, RRAM device was fabricated using tantalum oxide (TaOx) as a resistive switching insulating oxide layer, which was sandwiched between two conducting electrodes, namely Ag and ITO. RF magnetron sputtering was used to deposit the insulating layer of TaOx at room temperature on the ITO substrate. Further, X-ray reflectivity and hard X-ray photoelectron spectroscopy analyses were conducted to find the thickness, roughness, and elemental composition of the deposited TaOx films. Using a semiconductor analyzer, the RRAM cell's first DC switching characteristics were determined. The data acquired exhibited a resistance ratio (R HRS/R LRS) of 120 showing a good distinction between the two-resistance states. Additionally, a thorough investigation was conducted to examine the electrical conduction mechanism occurring inside the fabricated RRAM device.

Enhancing efficiency of photoelectrochemical water splitting using zinc vanadate nanosheets (ZV) on manganese vanadate needle flowers (MV) supported by carbon nanofibers

Zinc and Manganese vanadates are highly regarded as potential photoanode materials for photoelectrochemical (PEC) water splitting due to their limited bandgap, varying optical and electrical characteristics based on their composition, and robust nature. To advance the practical use these materials, it is essential to creating precisely composed and structured Zinc and Manganese vanadates to enhance their overall effectiveness. In this work, we employed various morphologies, such as nanobelt flower like Zinc vanadate (ZV), nano-needle like Manganese vanadate (MV), a composite with ZV and MV, and a ZV-MV@CNF ternary composition. These novel morphologies grown on ITO substrate using a simple, hydrothermal approach without using any seed layer. The structural, surface, and optical examinations confirmed that the ZV-MV@CNF catalyst had superior visible light absorption, accelerated charge transfer, heterojunction interface between ZV and MV, and increased electron mobility, leading to outstanding photoelectrochemical performance. The photocurrent density of the ZV-MV@CNF photoanode reached 6.59 mA cm−2 at 1 V versus Ag/AgCl in a 0.25 M KOH solution under the illumination light. These results are ∼3.00, 3.52, and 1.28 times greater than the pristine ZV, MV, and ZV-MV, respectively. The fine-tuned ZV, MV, ZV-MV, and ZV-MV@CNF electrodes showed applied bias photon to current efficiency (ABPE) values of 0.09 %, 0.06 %, 0.14 %, and 0.18 %, respectively. The improved photoelectrochemical behavior of the ZV-MV@CNF electrode is credited to the excellent light absorption, and the remarkable catalytic and charge transport capabilities of CNFs. Therefore, these experimental results and characterization analysis suggested that advanced hierarchical nanostructures hold significant promise for water splitting applications.

Electrical and surface properties of chemically deposited SrTiO3 films on ITO/glass substrate

In the present communication, for understanding the properties of thickness dependent STO/ITO thin films, the films were prepared using sol–gel sputtering technique wherein, different STO thickness are grown over ITO substrate. The structural properties understood using the XRD patterns wherein, observation shows the presence of amorphous STO without any detectable impurities. The Microstructural and cross-section analysis gives insight information of the films with batter distribution of grain and upper portion (STO) and lower portion (ITO) respectively which gets modifies with different thicknesses. The elemental composition of the studied films observed using EDAX and XPS spectrum reveals the only presence of required material with homogeneous distribution of all elements. From the a.c. conductivity and impedance spectroscopy the electrical properties of the films were measured wherein, for understanding the insight information’s the theoretical model such as; Jonscher’s power law, and Nyquist plot were fitted. The alternation of the properties can be studied using grain, grain boundaries, thickness of the film and different derived parameters.

High stability and photocatalytic activity of N-doped ZrO2 thin films

Undoped and nitrogen-doped ZrO2 thin films were obtained by HiPIMS on ITO/glass substrates. To stabilize their structure, the films were subjected to a heat treatment. The properties of the heat-treated films (structure, morphology, elemental composition of the atomic species at the films surface, optical band gap, wettability and oxidation performance of Rhodamine B) were correlated. Some properties of the studied films were compared with the ones of the as-deposited films previously reported. By nitrogen doping, zirconia thin film modifies its fundamental absorption edge, becoming absorbent in the visible domain. The heat treatment improves the hydrophilic properties of both undoped and N-doped films, the last one becoming super-hydrophilic. The photocatalytic activity under UV was investigated for three RhB concentrations. The degradation efficiency is higher than 90 % for both undoped and N-doped ZrO2 films, being better for the N-doped film. The studied films are exceptionally stable, keeping their oxidation properties almost unchanged after five degradation cycles, with a special remark for the N-doped film (the degradation efficiency around 93 %). The role of ITO substrate in charge carriers separation was investigated, based on the allowed band edges values, determined both for the films and ITO.

Electropolymerization of D-A-D type butterfly-shaped monomers based on triphenylamine-thiophene consisting of camphor substituted quinoxaline moiety for efficient electrochromism and supercapacitors

Two new butterfly-shaped monomers TTCQF and TTCQH consisting of camphor-substituted quinoxaline units as π-spacers were designed and synthesized, which were further electrochemical polymerized and deposited on ITO substrates for electrochromic energy storage devices. The present cross-linked polymer thin films PTTCQF and PTTCQH displayed prominent color changes with significant optical contrast in both the visible and near-infrared regions under external electrical stimuli. These two polymers showcased superior electrochromic performance, involving high optical contrast, fast switching speed, and good coloration efficiency. Additionally, both polymers demonstrated a high areal specific capacitance (12 mF/cm2 for PTTCQH and 9.97 mF/cm2 for PTTCQF) at a current density of 0.1 mA/cm2. Electrochromic energy storage devices based on these polymers were fabricated, and not only illuminated an LED bulb but also visually indicated the energy storage state, guaranteed their potential for applications in energy-saving smart windows. This work may provide valuable insights into the development of efficient cross-linked electrochromic energy storage polymers.

Electrodeposition of Au nanoparticles on ITO/PDAC/2H-MoS2 electrode for sensitive determination of bisphenol-A

Exfoliated 2H-MoS2 holds a promising future for various electrochemical applications. Nevertheless, its electrical conductivity and electrocatalytic efficiency are limited, restricting its standalone use. To address this limitation, this study proposes the electrochemical deposition of gold nanoparticles on layer-by-layer films of poly(diallyl dimethylammonium) hydrochloride interspersed with exfoliated 2H-MoS2, previously assembled on ITO substrate. This modified electrode, denoted as ITO/PDAC/2H-MoS2/Au, was assessed for its effectiveness in the voltametric detection of bisphenol-A (BPA). The optimal electrode architecture demonstrated a linear BPA detection range (0.9 µM-19 µM; R2 > 0.99), with a limit of detection of 23 nM. Notably, the electrochemical deposition was effective on both bare and film modified ITO substrates. However, it was on the ITO/PDAC/2H-MoS2/Au electrode that BPA detection achieved a reasonable level of sensitivity. During electrodeposition, superficial Mo(IV) is oxidized to Mo(VI) while sulfur vacancies are generated. These defect sites enhance the electrochemical activity of 2H-MoS2 and play a pivotal role in nucleating, growing, and immobilizing gold nanoparticles, which collectively enhance the sensor’s performance.

Photovoltaic Cell Prepared from Nanoparticles of CdS/CdTe on ITO Substrate and its Characterization

CdS/CdTe based photovoltaic cell has shown the markable efficiency. The CdS/CdTe nanoparticles are being synthesized and deposited on the ITO glass plate. ITO glass has a large bandgap of about approximately 3.6 eV and is suitable to use in the fabrication of photovoltaic cell. As ITO behaves as negative terminal, it is used as front layer for capturing the light intensity. During fabrication of photovoltaic cell, the deposition of Cadmium sulphide and Cadmium telluride nanoparticles layer was done by brush painting technique. The CdS layer is used as window layer and CdTe acts as absorbing layer. The window layer’s primary function is to absorb light particularly in the visible region of the spectrum to generate electricity. The CdS layer forms p-n junction with the CdTe layer. The nanoparticles of CdS and CdTe have been synthesized first and optical characterization was carried out using UV-visible spectroscopy to obtain bandgap of CdTe and CdS. Structural characterization was being obtained by XRD. The size of the nanocrystallites of CdS and CdTe have been obtained by Debye Scherrer equation and the result was 1.64 nm and 4.09 nm respectively. The CdTe layer which was used as absorbing layer consists of high optical absorption coefficient with high mobility, good carrier lifetime and an enhanced properties of crystallographic. Silver paste was used as a back contact for good conduction.

Unraveling the Heat- and UV-Induced Degradation of Mixed Halide Perovskite Thin Films via Surface Analysis Techniques.

In recent years, organic-inorganic hybrid perovskite materials have become one of the most promising materials in the new generation of solar cells. These perovskites can provide excellent photoelectric properties after a simple fabrication process. Although perovskite solar cells have achieved high power conversion efficiency, instability concerns regarding material exposure to heat, moisture, air, and UV light present hindrances to commercialization. In this study, three kinds of perovskites (MAPbI3, MAPbI3-xBrx, and MAPbI3-xClx) were used to investigate the crystal stability upon exposure to heat and UV light. SEM, XRD, and FTIR were used to observe the surface morphology, crystal structure, and functional groups of the perovskite thin films. XPS was used to examine the surface composition and chemical state of the perovskite thin films under different conditions. Among these three types of perovskites, it was found that the MAPbI3-xBrx crystal demonstrated the best stability. ToF-SIMS was used to confirm the molecular distribution of the MAPbI3-xBrx films upon exposure to heat and UV light at different depths. ToF-SIMS revealed that [Pb]+ and [PbI]+ aggregated at the interface between the perovskite and ITO substrate after 14 days of thermal treatment. On the other hand, [Pb]+ and [PbI]+ were distributed uniformly after 3 days of UV exposure. This study systematically analyzed and revealed the thermal- and UV-induced degradation process of three perovskite films by using surface analysis techniques. It was concluded that bromine-doped perovskite films had better stability, and UV light caused more severe damage than heat.

An investigation of glass, ITO, and quartz transparent substrates on Pd/SnO2 hydrogen sensor structure and sensitivity

Hydrogen energy has great potential as a fuel for the future, but its leakage poses a major threat. Thus, our main concern is to detect it very quickly. In this work, we investigate the effect of transparent glass, ITO, and quartz substrates on hydrogen gas sensing properties of magnetron sputter- deposited Pd-capped SnO2 (Pd/SnO2) thin film sensor material. The XRD study reveals that all Pd-capped SnO2 thin films deposited on different substrates has polycrystalline tetragonal structure. Sensors fabricated on quartz substrates exhibit homogeneous grain distributions at the interface, whereas sensors deposited on ITO and glass substrates have randomly size grains distribution at the interface. Sensors deposited on glass and ITO show lower sensitivity compare to sensors fabricated on quartz substrate at a working temperature of 250°C. The Pd/SnO2 sensor @ quartz shown a maximum response of ∼ 9.3 and better stability toward 500 ppm hydrogen gas, and a fast response/recovery time of 30/26 s for 5 ppm hydrogen gas. The sensor @ quartz substrate shows a small reduction in response and baseline at 60% RH. The sensor fabricated on quartz substrate exhibits better selectivity toward hydrogen gas and significant stability for long duration of three months in high humid conditions. The performance of the Pd/SnO2 thin sensor fabricated on quartz proves that the sensor based on average grains have a wide potential for real hydrogen gas monitoring.

A pure pyrochlore phase ferroelectric thin film diode for optoelectric artificial synapse

In this work, Au/Bi2Ti2O7/ITO ferroelectric diodes based on Schottky barrier were fabricated on ITO substrates by the sol-gel method. The device has a simple structure and good diode performance. Under UV light irradiation at 23.5 mW/cm2, the device exhibits an open-circuit voltage of 0.31 V and a short-circuit current of −0.0425 μA. It shows that the device has good optoelectronic properties. Au/Bi2Ti2O7/ITO ferroelectric diodes also exhibited behaviors similar to biological synapses, including long-term plasticity, short-term plasticity, paired-pulse facilitation, and spike-timing-dependent plasticity when stimulated by pulses. We also build convolutional neural networks and use the MNIST dataset for handwritten digit recognition.

Tin Oxide/Amphiphilic Polymer Double‐Layered Hole Transporter for High‐Efficiency Tin Perovskite Solar Modules

AbstractAn exquisite, engineering of two poor hole transporting materials (HTMs, SnO, and PDTON) to form an excellent double‐layered HTL (SnO/PDTON) for inverted tin‐perovskite solar modules (TPSMs) is developed. SnO/PDTON has better photovoltaic performance than the commonly used PEDOT:PSS HTM when large‐area TPSMs are fabricated. Thermally evaporated SnO (that is a simple, available oxide with high hole mobility, good transparency, and adjustable frontier orbitals energy levels) film is used as a main hole transporting layer (HTL). Amphiphilic polymer PDTON (having the amine and ether groups on the side chains) film is used as a Co‐HTL, cross‐linker, passivator, and interface modification agent, as unveiled various physicochemical studies. Double‐layered SnO/PDTON with a flat morphology and good affinity toward perovskite precursor solution creates also a proper surface for depositing large‐area, high‐quality TPsk film. Therefore, TPSM (25.2 cm2 active area on 10 cm × 10 cm ITO substrate) based on double‐layered SnO/PDTON HTL achieving an efficiency over 10% with a negligible current hysteresis is reported for the first time. This study emphasizes not only the exquisite design of combining the specific characteristics of two prosaic HTMs to become a good double‐layered HTL but also gives a direction toward fabricating TPSMs to be applied in all‐perovskite tandem solar module.

Fabrication and analysis of ZnO and Al-doped ZnO films using the SILAR technique

In this study, undoped ZnO and Al-doped ZnO thin films were successfully deposited on ITO substrates at various concentrations using the SILAR method. The deposited thin films underwent characterization via SEM/EDS, XRD, and UV-Vis spectroscopy. XRD analysis revealed that the thin films crystallized at the nanoscale, with crystallization quality varying based on the concentration of Al dopant. SEM/EDS analysis indicated a notable influence of Al doping concentration on the morphology of ZnO thin films. UV-Vis analysis highlighted significant differences in both the optical band gap values and transmittance of the thin films depending on the dopant used.

Twisted leaf like ZnO-flake-like BiOI@CNF grown on ITO substrate as a nanostructured pioneering platform for photoelectrochemical water splitting

Despite ZnO nanostructures garnering significant attention for photoelectrochemical (PEC) water splitting, the quest for efficient ZnO-based photoelectrodes with optimal light absorption, effective electron-hole separation, and transfer remains a challenge. The formation of ZnO heterojunctions with lower bandgap nanostructures of semiconductors has emerged as a strategy to enhance charge transfer while mitigating recombination rates. Additionally, the introduction of carbon nanofibers (CNFs) to these heterojunctions serves to further suppress recombination by electron trapping and enhances catalytic active sites, thereby elevating PEC performance. In this study, twisted leaf-like ZnO, flake-like BiOI, ZnO-BiOI nanostructure heterojunctions, and ZnO-BiOI@C composites were synthesized through a solvothermal method. Notably, the ZnO-BiOI@C photoelectrode exhibited outstanding performance, achieving a photocurrent density of 5.6 mA/cm2 through linear sweep voltammetry under light illumination. Each synthesized photoelectrode demonstrated robust photocurrent responsiveness and excellent stability under chopped conditions for up to 1150 s with a 50 s interval. This remarkable stability is attributed to the unique and stable morphological characteristics and strong crystallinity of the synthesized materials. The formed heterojunction between ZnO-BiOI was found to extend light absorption capabilities, while the incorporation of CNFs effectively trapped electrons from the heterojunction's conduction band, enhancing overall water splitting performance. The results underscore the potential of the ZnO-BiOI@C composite as a high-performing photoelectrode for PEC applications, emphasizing the importance of morphological and compositional considerations in advancing PEC technologies.

ZnO/ITO, Sn and Cu Doped ZnO/ITO Films as an Photoanode for Solar Cell: Production and Characterizations

Undoped ZnO and Sn- and Cu-doped ZnO thin films were fabricated on ITO substrates via the SILAR method for this study. The films were then subjected to structural, surface, optical, and electrical characterization. The undoped ZnO thin films displayed a spherical surface morphology, while the Sn-doped ZnO thin films exhibited a nano-flower surface morphology. On the other hand, the Cu-doped ZnO thin films demonstrated a relatively thicker and flat layer, as well as a fractured surface morphology that resulted in voids. The level of crystallization and transmittance values augmented upon doping. With Cu doping, n-p heterojunction structure was obtained from ZnO/ITO films. Hence, it is inferred that the generated Cu doped ZnO/ITO films can serve as alternative transparent conductive films (TCO) due to their low resistivity.

Ecofriendly Cellulose Substrate‐Based Flexible Transparent Electrode for Flexible Organic Solar Cells with Efficiency Over 18%

Flexibility is a key advantage of organic solar cells (OSCs), and the power conversion efficiencies (PCEs) of flexible OSCs (FOSCs) are primarily constrained by flexible transparent electrodes (FTEs). While much attention has been devoted to the study of conductive layers on FTEs, the importance of flexible substrates in influencing the properties of FTEs and the performance of FOSCs is often overlooked. In this study, an FTE is developed using an eco‐friendly ethyl cellulose (EC) substrate and silver nanowires (AgNWs) as the conductive electrode. The FTE exhibits a high transmittance of up to 88% at 550 nm and a low sheet resistance of 17.65 Ω/□. Consequently, FOSCs based on the EC/PI FTEs achieve a remarkable PCE of 18.05%, comparable to that on the rigid ITO substrate. The flexible devices also demonstrate excellent bending and peeling durability even under extreme bending conditions.

Synthesis and characterization of CZTS and Cu2-xAgxZnSnS4 thin films for the application of solar cells

We report on colloidal Cu2ZnSnS4 (CZTS) and Cu2-xAgxZnSnS4 (X=0.25) nanoparticles synthesis by sol-gel spin coating process and hot injection method. The colloidal nanoparticles were deposited on ITO substrates by using spin-coating techniques. The deposited thin films were characterized by X-ray diffraction (XRD), UV-visible spectrometer, FE-SEM, Raman spectroscopy and Keithley 2450 Source meter. XRD reveals that the crystal structure of CZTS is confirmed tetragonal structure with peak (112) and observed the changes to wurtzite peak (002) due to the presence of Ag. UV visible spectra show that the optical band gap of CZTS nanoparticles decreases from 2 eV to around 1.75 eV, and there is a significant improvement in absorption coefficient when the sample is prepared under a nitrogen atmosphere. FESEM captured the microstructure image of CZTS and Cu2-xAgxZnSnS4. Photoluminescence (PL) reveals the emission peaks and Raman spectra investigate the secondary phases present. XPS confirms the presence of each element and their oxidation state. Further, electrical properties are studied using the four-probe method at room temperature. CZTS offers optical and electrical properties, which allow it to be suitable for thin-film solar cell absorber layers, and Ag doping enhances its properties.

CPE-Na-Based Hole Transport Layers for Improving the Stability in Nonfullerene Organic Solar Cells: A Comprehensive Study.

Organic photovoltaic (OPV) cells have experienced significant development in the last decades after the introduction of nonfullerene acceptor molecules with top power conversion efficiencies reported over 19% and considerable versatility, for example, with application in transparent/semitransparent and flexible photovoltaics. Yet, the optimization of the operational stability continues to be a challenge. This study presents a comprehensive investigation of the use of a conjugated polyelectrolyte polymer (CPE-Na) as a hole layer (HTL) to improve the performance and longevity of OPV cells. Two different fabrication approaches were adopted: integrating CPE-Na with PEDOT:PSS to create a composite HTL and using CPE-Na as a stand-alone bilayer deposited beneath PEDOT:PSS on the ITO substrate. These configurations were compared against a reference device employing PEDOT:PSS alone, as the HTL increased efficiency and fill factor. The instruments with CPE-Na also demonstrated increased stability in the dark and under simulated operational conditions. Device-based PEDOT:PSS as an HTL reached T80 after 2500 h while involving CPE-Na in the device kept at T90 in the same period, evidenced by a reduced degradation rate. Furthermore, the impedance spectroscopy and photoinduced transient methods suggest optimized charge transfer and reduced charge carrier recombination. These findings collectively highlight the potential of CPE-Na as a HTL optimizer material for nonfluorine OPV cells.