Indium Tin Research Articles

Improving the Nonvolatile Memory Characteristics of Sol-Gel-Processed Y2O3 RRAM Devices Using Mono-Ethanolamine Additives.

In this study, Y2O3-based resistive random-access memory (RRAM) devices with a mono-ethanolamine (MEA) stabilizer fabricated using the sol-gel process on indium tin oxide/glass substrates were investigated. The effects of MEA content on the structural, optical, chemical, and electrical characteristics were determined. As the MEA content increased, film thickness and crystallite size decreased. In particular, the increase in MEA content slightly decreased the oxygen vacancy concentration. The decreased film thickness decreased the physical distance for conductive filament formation, generating a strong electric field. However, owing to the lowest oxygen vacancy concentration, a large electrical field is required. To ensure data reliability, the endurance cycles across several devices were measured and presented statistically. Additionally, endurance performance improved with the increase in MEA content. Reduced oxygen vacancy concentration can successfully suppress the excess formation of the Ag conductive filament. This simplifies the transition from the high- to the low-resistance state and vice versa, thereby improving the endurance cycles of the RRAM devices.

Self-doped conducting polyaniline bearing phosphonic acid as a hole transport layer in organic photovoltaics

A self-doped conducting polyaniline was used as a hole transport layer (HTL) in organic photovoltaics (OPVs) [indium tin oxide/HTL/zinc-phthalocyanine/C70/bathocuproine/Al]. This polyaniline was characterized by phosphonic acid neutralized with pyridine (PMAP:Py). The current–voltage characteristics were evaluated and were comparable to those of the devices using a conventional hole transport material, poly(3,4-ethylenedioxythiophene) doped with poly(styrenesulfonate) (PEDOT:PSS). PMAP:Py-based OPVs stored in both nitrogen and ambient atmosphere had a longer lifetime than PEDOT:PSS-based ones.

An unusual impedimetric biosensor design based on 3-MPDS for highly sensitive detection of AFB1 in food samples

Aflatoxin B1 (AFB1), a mycotoxin produced by fungi of the genus Aspergillus, particularly Aspergillus flavus, is recognized as the aflatoxin with the highest carcinogenic and mutagenic potential. This study presents a cost-effective, disposable AFB1 biosensor system based on 3-mercaptopropyltrimethoxysilane (3-MPDS) and the highly sensitive impedance technique. The surfaces of the ITO-PET (indium tin oxide/polyethylene terephthalate) electrodes were modified with 3-MPDS, and N-hydroxysuccinimide (NHS) was used as a crosslinker. Electrochemical impedance spectroscopy (EIS) and cyclic voltammetry (CV) techniques were employed for immobilization, optimization, and analytical studies. Additionally, the surface morphology of the biosensor was analyzed using scanning electron microscopy (SEM) and atomic force microscopy (AFM). The biosensor demonstrated a linear range from 0.01 fg/mL to 200 fg/mL, with a limit of detection (LOD) of 0.01 fg/mL and a limit of quantification (LOQ) of 0.04 fg/mL. Finally, the proposed biosensor was tested and validated with real food samples, including rice, peanuts, milk, chili pepper, and corn.

Preparation of poly(5‐ferrocenyl‐dipyrromethane) as sensor for electrochemical removal of aluminum and barium ions in real water samples

In this work, 5‐ferrocenyl‐dipyrromethane (Fc‐DPM) synthesized from the pyrrole and ferrocenecarboxaldehyde condensation was electrochemically deposited on a gold (Au) electrode and used to remove metal ions found in rural waters. The structural analysis of Fc‐DPM was recorded by means of nuclear magnetic resonance (NMR) techniques. The Fc‐DPM was electrochemically coated on an indium tin oxide‐polyethylene terephthalate (ITO‐PET) surface, and the resulting Fc‐DPM/ITO‐PET was characterized using scanning electron microscopy (SEM)–energy dispersive X‐ray (EDX) analysis. The heavy metal and mineral content of four real water samples from the same rural area were determined by inductively coupled plasma mass spectrometry (ICP‐MS) before and after electrochemical removal. The proposed Fc‐DPM/Au electrode was successfully applied for aluminum ion (Al3+) and barium ion (Ba2+) removal for the first time, and the limit of detection (LOD) was calculated as 0.003 and 0.217 ppb for Ba2+ and Al3+, respectively.

Non-contact intelligent sensor for recognizing transparent and naked-eye indistinguishable materials based on ferroelectric BiFeO3 thin films

At present, the research on ferroelectric photovoltaic materials mainly focuses on photoelectric detection. In the context of the rapid development of the Internet of Things (IoT), it is particularly important to use smaller thin-film devices as sensors. In this work, an indium tin oxide/bismuth ferrite (BFO)/lanthanum nickelate device has been fabricated on an F-doped tin oxide glass substrate using the sol–gel method. The sensor can continuously output photoelectric signals with little environmental impact. Compared to other types of sensors, this photoelectric sensor has an ultra-low response time of 1.25 ms and ultra-high sensitivity. Furthermore, a material recognition system based on a BFO sensor is developed. It can effectively identify eight kinds of materials that are difficult for human eyes to distinguish. This provides new ideas and methods for developing the IoT in material identification.

Carbon nanotube-grid infrared transparent electrodes for flexible electrochromic devices with visible to mid-infrared dual-band modulation

Flexible mid-infrared electrochromic devices (MIR-ECDs) have attracted wide attention due to the growing demands for thermal camouflage and body comfort. However, the normal conductive films (e.g., indium tin oxide/polyethylene terephthalate (ITO/PET) films) are unsuitable for MIR-ECDs due to low infrared transmittance. Herein, the infrared transparent carbon nanotube (CNT) grid films were prepared by designing the grid structure. The infrared transmittance of CNT grid film could reach 72 %; meanwhile, the visible transmittance could reach 75 %. The CNTs exhibited infrared modulation under different voltages due to the doping/de-doping of ions in electrolytes into the CNT network. The flexible electrochromic devices with visible to mid-infrared dual-band modulation were prepared by using CNT grid film as the electrode and poly (3,4 ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS) as the electrochromic layer, which could realize the infrared synergistic modulation of PEDOT:PSS and CNT grid in the mid-infrared range and reversible color changes between light blue and dark blue in the visible range, showing promising applications in adaptive camouflage and thermal management.

Synthesis of nanostructured zinc oxide and its composite with carbon dots for DSSCs applications using flexible electrode

ZnO nanowires (ZnO NWs), ZnO nanoparticles (ZnO NPs) and carbon dots (C-dots) were synthesized by hydrothermal, sol-gel and hydrothermal methods respectively. They were also characterized and applied for dye sensitized solar cells (DSSCs). The effects of C-dots on ZnO NWs and ZnO NPs have been evaluated. The C-dots were used at a mole ratio of citric acid (CA) to ethylene diamine (EDA) of 1 : 1.5. These C-dots were found to enhance the performance of the flexible electrode DSSCs. After the addition of C-dots, the power conversion efficiency (PCE) of ZnO NPs was boosted to be two times higher than that of ZnO NPs DSSCs without C-dots. Similarly, the ultraviolet (UV)-band revealed a blue shift, resulting in a lower band gap and a reduced charge transfer resistance, which can enhance the PCE of DSSCs. The loaded quantity on the flexible electrode substrate made of polyethylene terephthalate (PET) was optimized (50 mg). For DSSCs, the PET flexible electrode conductive polymer has produced positive outcomes. For ZnO NWs and ZnO NWs@C-dots, the PCE values were 1.45% and 4.25%; while for ZnO NPs and ZnO NPs@C-dots, they were 2.34% and 5.81%, respectively. This work achieved remarkable and competitive performance when compared to solid (indium tin oxides/glass)-based substrate.

Enhancement of electrical properties by CuS–PVP nanocomposite on the ZnO/polymer heterojunction

AbstractA nanocomposite matrix of covellite–polyvinylpyrrolidone (CuS–PVP) was synthesized through a solution processing method and applied via spin coating onto hydrothermally grown zinc oxide (ZnO) nanorods. Characterization techniques, including X‐ray powder diffraction and scanning electron microscopy, confirmed the successful decoration of chain‐like CuS–PVP polymer composites onto hexagonal ZnO nanorods. The UV‐vis spectroscopy revealed an absorption peak at 372 nm, indicating excitonic absorption of ZnO, and a reduction in the band gap from 3.11 to 2.59 eV upon CuS–PVP polymer decoration, enhancing light harvesting efficiency. Photoluminescence spectra demonstrated the lowest charge carrier recombination rate in the ZnO/CuS–PVP sample, promoting efficient charge separation and transportation, supported by Fourier‐transform infrared analysis indicating chemical bonding. Subsequently, the impact of CuS–PVP as an insertion layer in the ZnO/poly(3,4‐ethylenedioxythiophene)‐poly(styrenesulfonate) (PEDOT:PSS) inorganic–organic heterojunction was investigated. Favorable band alignment between ZnO, CuS–PVP, and PEDOT:PSS improved conduction, increasing current from 0.3394 to 1.14 mA for D2 (poly‐ethyleneterephthalate/Indium tin oxide/ZnO/PEDOT:PSS/Al) and D1 (poly‐ethyleneterephthalate/Indium tin oxide/ZnO/CuS–PVP/PEDOT:PSS/Al) at a +2 V bias. Transient photo‐responses (J–t) at 0 V bias revealed decreased rise and fall times from 0.382 and 1.154 s to 0.301 and 0.229 s for D2 and D1 devices, respectively. This novel approach provides control over charge carrier transport characteristics at the interface, potentially benefiting self‐powered photo‐detection in optoelectronic devices.

Direct and Sensitive Electrochemical Determination of Total Antioxidant Capacity in Foods Using Nanochannel-Based Enrichment of Redox Probes.

Simple and sensitive determination of total antioxidant capacity (TAC) in food samples is highly desirable. In this work, an electrochemical platform was established based on a silica nanochannel film (SNF)-modified electrode, facilitating fast and highly sensitive analysis of TAC in colored food samples. SNF was grown on low-cost and readily available tin indium oxide (ITO) electrode. Fe3+-phenanthroline complex-Fe(III)(phen)3 was applied as the probe, and underwent chemical reduction to form Fe2+-phenanthroline complex-Fe(II)(phen)3 in the presence of antioxidants. Utilizing an oxidative voltage of +1 V, chronoamperometry was employed to measure the current generated by the electrochemical oxidation of Fe(II)(phen)3, allowing for the assessment of antioxidants. As the negatively charged SNF displayed remarkable enrichment towards positively charged Fe(II)(phen)3, the sensitivity of detection can be significantly improved. When Trolox was employed as the standard antioxidant, the electrochemical sensor demonstrated a linear detection range from 0.01 μM to 1 μM and from 1 μM to 1000 μM, with a limit of detection (LOD) of 3.9 nM. The detection performance is better that that of the conventional colorimetric method with a linear de range from 1 μM to 40 μM. Owing to the anti-interfering ability of nanochannels, direct determination of TAC in colored samples including coffee, tea, and edible oils was realized.

Multilayer Fe3O4-doped ITO indium saving indium tin oxide thin films

Multilayer Fe3O4-doped indium saving indium-tin oxide (ITO) thin films were fabricated by sputtering method. Double-layered Fe3O4-doped indium saving indium-tin oxide (ITO) thin films consisted of 12 nm layer of conventional indium tin oxide (90 mass% In2O3 and 10 mass% SnO2) and 138 nm layer of indium saving indium-tin oxide (50 mass% In2O3, 50 mass% SnO2 and Fe3O4-doped) were grown on preheated at 523 K glass substrates. Obtained polycrystalline ITO thin films exhibit volume resistivity of 416 µΩcm, electron mobility 28 cm2/V·s, carrier density 5.3 × 1020 cm−3 and average optical transmittance above 85% in visible range of spectrum.

Flexible and Self‐Powered Photoelectrochemical‐Type Solar‐Blind Photodetectors Based on Ag Nanowires‐Embedded Amorphous Ga2O3 Films

AbstractThe development of flexible electronics for detecting solar‐blind deep ultraviolet (UV‐C) light holds great promise for emerging technologies. Here, flexible photoelectrochemical photodetectors (PEC‐PDs) are demonstrated for self‐powered solar‐blind UV‐C sensing based on one‐step radio frequency sputtered amorphous gallium oxide (a‐Ga2O3) thin films on indium tin oxide‐coated polyethylene naphthalate (ITO/PEN) substrates in a simple and low‐cost manner. Surface functionalization of the ITO/PEN substrates with silver nanowires (Ag NWs) successfully embedded within the a‐Ga2O3 films significantly enhances the optoelectronic performance. Incorporating Ag NWs reduces charge transfer resistance and potential barrier, while enhancing built‐in electric field at the Ag NWs/a‐Ga2O3 interface, synergistically facilitating efficient electron transport. Consequently, the Ag NW‐modified PEC‐PDs exhibit approximately two‐fold increases in key metrics including responsivity (11.23 mA W−1) and response times (0.07/0.09 s rise/decay) under 254 nm illumination compared to pristine devices. Moreover, the Ag NW‐functionalized PEC‐PDs demonstrate superb mechanical flexibility and fatigue durability, maintaining ≈95% of the initial photoresponse current and responsivity after 500 bending cycles. This work provides valuable insights into designing high‐performance flexible self‐powered PEC‐PDs through ingenious photoanode engineering.

Controlled Calcium Oxalate Crystals Obtained by Electrocrystallization on Electrospun Polycaprolactone Fibers Loaded with Zarzaparrilla ( Herreria stellata ).

Calcium oxalate (CaOx) is known to grow on organic matrices and is often associated with the formation of kidney stones. Therefore, it is crucial to understand the nucleation and growth mechanisms. This study investigates the role of electrospun polycaprolactone (PCL)-loaded zarzaparrilla (ZP) (Herreria stellata) in the electrocrystallization (EC) of CaOx. Electrospinning (ES) was used to prepare PCL meshes with random (R) and aligned (A) fiber orientations. CaOx particles were grown directly on conductive tin indium oxide (ITO) glass modified with electrospun ZP-loaded PCL meshes by EC. The CaOx crystals after EC were measured by chronopotentiometry (CP), optical microscopy (OM), scanning electron microscopy (SEM), and X-ray diffraction (XRD), which showed that the ZP additive and PCL fiber orientations are key factors for CaOx nucleation.

Thermodynamic activity in Zn–Cu–Sn–In liquid solder alloys: a comprehensive analysis using the molecular interaction volume model

The molecular interaction volume model (MIVM) was employed to estimate the activity of each component in Zinc–Copper–Tin–Indium (Zn–Cu–Sn–In) quaternary liquid alloys at 1023 K, keeping indium content constant, i.e. xIn = 0.1, and varying molar ratios of Cu and Sn (xCu/xSn). Furthermore, the model has been used to determine the activity of each component of all sub-binary systems, namely Cu–Zn at 1200 K, Sn–Zn at 750 K, In–Zn at 700 K, Cu–Sn at 1400 K, Cu–In at 1073 K, In–Sn at 700 K, and Zn–Cu–In liquid ternary alloys at 1023 K for three molar ratios of Cu and In, i.e. xCu/xIn = 1:2, 1:1, and 2:1. We found that the activity deviations of Zn from Raoult’s law transform from positive to negative as the xCu/xIn ratio changes from 1:2 to 2:1. The estimated values were analyzed with the correspondent experimental results in the case of ternary and all the binary liquid alloys. There is a notable agreement observed between theoretical forecasts and practical findings in both binary and ternary systems. This work provides a thorough thermodynamic study of the Zn, Cu, Sn, and In quaternary systems.

Bathocuproine, an old dog, new tricks for boosting the performance of perovskite solar cells

Perovskite solar cells (PSCs) have demonstrated extensive prospects for future applications. However, defects remain the crucial factor that impedes their further advancement in performance, and passivation of the interfaces (such as the buried and/or top interfaces) is regarded as one of the most effective approaches. Herein, we aim to address another important interface, namely, the indium tin oxide/electron transport layer (ITO/ETL) interface in n-i-p structured devices. Since electron transport layers are typically fabricated using commercial nanotin dioxide, which often displays insufficient density. To combat this, we employ the most commonly used bathocuproine (BCP) material to treat the ITO/ETL interface. The incorporation of BCP diminishes the direct contact between the perovskite and ITO layers while also passivating the buried interface and adjusting the crystal orientation of perovskites. Furthermore, the substrate layer exhibits improved transparency, consequently elevating the utilization rate of light by perovskite. As a result, the BCP-based PSC exhibits an impressive efficiency greater than 22%, surpassing the control one of 19.91%, and simultaneously demonstrates excellent stability. Notably, the optimization of this interface has universal applicability for the improvement of PSCs performance.

The characterization of Ag-doped tin indium oxide/copper electrodes prepared by cold pressing method and their electrocatalytic efficiency in hydrogen production

In the present study, tin indium oxide (SnIn2O3) powder was synthesized by hydrothermal technique. In order to improve the structural property of SnIn2O3, a small amount of silver (Ag) nanoparticles was added into SnIn2O3 powder. Finally, the prepared Ag-doped SnIn2O3 (Ag@SnIn2O3) were embedded into copper (Cu) powder with different ratios. The electrocatalytically improved hetero-structured Ag@SnIn2O3/Cu materials were obtained by cold pressing method. The structural and morphological properties of different Ag@SnIn2O3/Cu materials were studied via X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). XRD pattern depicted In2O3 have both cubic and hexagonal crystal structures. FE-SEM images show that Ag@SnIn2O3 nanoparticles are homogeneously dispersed into Cu powder. The size of nanoparticles of Ag@SnIn2O3/Cu materials increases with increasing the ratio of Ag@SnIn2O3. Electrochemical impedance spectroscopy (EIS) and potentiodynamic (PD) polarization tests were carried out to investigate the electrocatalytic activities of the materials toward hydrogen evolution reaction (HER). Energy consumption and energy efficiency values for the HER on the materials were also calculated. Furthermore, the polarization resistances of the 1-Ag@SnIn2O3/Cu, 2.5-Ag@SnIn2O3/Cu, 5-Ag@SnIn2O3/Cu, and 10-Ag@SnIn2O3/Cu materials were determined as 127.4, 103.1, 552.4, and 558.7 Ω cm2, respectively after 5 days of electrolysis periods.

Integrated scanning electrochemical cell microscopy platform with local electrochemical impedance spectroscopy using a preamplifier.

Local electrochemical impedance spectroscopy (LEIS) has emerged as a technique to characterize local electrochemical processes on heterogeneous surfaces. However, current LEIS heavily relies on lock-in amplifiers that have a poor gain effect for weak currents, limiting the achievements of high-spatial imaging. Herein, an integrated scanning electrochemical cell microscopy is developed by directly collecting the alternating current (AC) signal through a preamplifier. The recorded local current (sub nA-level) is compared with the initial excitation signal to get the parameters for Nyquist plotting. By integrating this method into scanning electrochemical cell microscopy (SECCM), an image of LEIS at the Indium Tin Oxide/gold (ITO/Au) electrode is obtained with a spatial resolution of 180 nm. The established SECCM platform is integrated such that it could be positioned into the limited space (e.g. glove box) for real characterization of electrodes.

Development of Triboelectric Nanogenerators Using Novel 3D Printed Polymer Materials

Triboelectric nanogenerators (TENGs) are becoming attractive devices for harvesting mechanical energy. 3D printing (3DP) is a newly reported technique for the development of this device. This technique is not fully explored for the fabrication of triboelectric materials and compatible printing processes. Herein, three main 3DP techniques including powder‐based multijet fusion, resin‐based polyjet fusion, and filament‐based fused deposition modeling are utilized to investigate new sets of 3DP triboelectric materials. Mechanical to electrical conversion efficiency of 3D printed and commercially available negative and positive triboelectric materials are compared and investigated. Polyamide ‐12 (PA12), Veroclear, acrylonitrile‐styrene‐acrylate (ASA), copper‐coated polylactic acid (Cu‐PLA), polycarbonate (PC), and polyethylene terephthalate glycol (PETG) are fabricated using compatible 3D printing techniques. 3D‐printed PA12 is considered as a reference positive triboelectric layer. Meanwhile, 3D‐printed Veroclear, ASA, Cu‐PLA, PC, PETG, and commercial materials like Teflon sheets, PA6,6 conductive sheets, indium tin oxide‐coated polyethylene terephthalate, conductive‐nylon sheets, and PVDF membrane are selected as negative triboelectric materials. The maximum AC voltage of 80 V and maximum instantaneous current of 0.9 μA are produced by pairing 3DP‐PA12 and 3DP‐Veroclear under open circuit condition. This AC output is further converted to DC output using brdige rectifier circuitry to efficiently charge up the capacitor and glow series of 16 LEDs.

Solution‐Processed, Highly Crystalline, and Oriented MAPbI3 Thin Films by Engineering Crystal‐Growth Kinetics

Growing oriented and monocrystalline layers of lead halide perovskites over device substrates helps to harness their outstanding optoelectronic properties. Epitaxial growth of lead halide perovskites for device fabrication is limited by the lack of lattice‐matched substrates and the requirement of compact pinhole‐free films. Most optoelectronic devices use amorphous substrates, hindering oriented epitaxial growth. Herein, highly crystalline methylammonium lead iodide (MAPbI3) thin films over amorphous substrates are demonstrated by meticulously optimizing the nucleation and growth kinetics in spin‐coating. The “epitaxial‐like” films enable large‐area crystalline layer fabrication, with larger than 100 μm spherulitic grains oriented along [200] and [224] planes. The compact, highly crystalline, and oriented films of MAPbI3 formed over indium tin oxide/SnO2 are used to fabricate perovskite solar cells (PSCs) with an area of 1 cm2. Despite the perovskite films being highly oriented and crystalline, the PSCs’ performances highlight the critical role the interfaces play in photovoltaic cells.

Optimizing the Performance of Tin‐Based Perovskite Solar Cells Employing 2D Tungsten Disulfide as an HTL by Numerical Simulation

Perovskite solar cells (PSC) have emerged as a prominent research area in solar cell development owing to their high‐efficiency and low‐cost photovoltaic technology. However, the transport layers typically employed in PSCs are organic materials, which may lead to unstable performance. In this work, a PSC with an indium tin oxide/WS2/FASnI3/Cd0.5Zn0.5S/Al configuration is proposed, and the parameters are optimized using the solar cell capacitance simulator‐1D program. In the present study, the impact of the WS2 layer thickness, electron‐transport layer material selection, absorber layer parameters, and interfacial defect states on the performance of the proposed solar cell is investigated. The optimized structure yields a power conversion efficiency of 23.1%, which is comparable to that of state‐of‐the‐art PSCs. The combination of an inorganic hole‐transport layer of WS2 presented in this work offers a novel approach to the development of PSCs.

Enhancement of the performance of a ZnO-based nanostructured flexible UV photodiode grown on the carbon clothe by piezo-phototronic effect

The current study aims to evaluate the piezo-phototronic effect on the performance of the prepared ZnO-based UV Photodiodes (PDs). To this end, the electrochemical method was employed to facilitate the growth of ZnO Nanowires (NWs) on the Carbon Clothe (CC) substrate. The results obtained from Scanning Electron Microscopy (SEM) and X-Ray Diffraction (XRD) analyses demonstrated well-grown ZnO NWs arrays with high coverage density and crystal quality on the substrate. The current-voltage (I–V) measurement was employed in the UV illumination and dark conditions to determine the photo-responsivity and detectivity of the prepared device to the UV light. In addition, the photocurrent and overall device performances were modified under UV illumination and applying compressive strain, given its role in increasing the barrier height. As a result, more photo-generated charge carriers can migrate to the electrode without recombination in comparison with free strain conditions. This phenomenon is known as the piezo-phototronic effect. Further, the findings of this study revealed that CC could be an appropriate alternative to the fabricated flexible PDs instead of other expensive flexible substrates such as Indium Tin Oxide/Poly-Ethylene Terephthalate (ITO/PET).