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Showing papers on "Indium tin oxide published in 2021"


Journal ArticleDOI
TL;DR: In this paper, a double-junction tandem OPV cell is fabricated by optimizing the photoactive layers with low voltage losses and developing an effective method to tune optical field distribution.
Abstract: Despite more potential in realizing higher photovoltaic performance, the highest power conversion efficiency (PCE) of tandem organic photovoltaic (OPV) cells still lags behind that of state-of-the-art single-junction cells. In this work, highly efficient double-junction tandem OPV cells are fabricated by optimizing the photoactive layers with low voltage losses and developing an effective method to tune optical field distribution. The tandem OPV cells studied are structured as indium tin oxide (ITO)/ZnO/bottom photoactive layer/interconnecting layer (ICL)/top photoactive layer/MoOx /Ag, where the bottom and top photoactive layers are based on blends of PBDB-TF:ITCC and PBDB-TF:BTP-eC11, respectively, and ICL refers to interconnecting layer structured as MoOx /Ag/ZnO:PFN-Br. As these results indicate that there is not much room for optimizing the bottom photoactive layer, more effort is put into fine-tuning the top photoactive layer. By rationally modulating the composition and thickness of PBDB-TF:BTP-eC11 blend films, the 300 nm-thick PBDB-TF:BTP-eC11 film with 1:2 D/A ratio is found to be an ideal photoactive layer for the top sub-cell in terms of photovoltaic characteristics and light distribution control. For the optimized tandem cell, a PCE of 19.64% is realized, which is the highest result in the OPV field and certified as 19.50% by the National Institute of Metrology.

157 citations


Journal ArticleDOI
TL;DR: In this article, an eco-friendly solvent protection (ESP) method for the fabrication of high-performance OSCs with stacked structures was presented, where non-aromatic and non-halogenated solvents are employed as protective agents to build SD devices with a configuration of indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS Clevios P VP Al 4083)/donor/protective solvent/acceptor/perylene diim
Abstract: The construction of organic solar cells with stacked structures by the sequential deposition (SD) of donor and acceptor films has great potential in industrial production, as it demonstrates little dependence on the ratio of donor and acceptor materials, solvents, and additives Herein, we present an eco-friendly solvent protection (ESP) method for the fabrication of high-performance OSCs with stacked structures Several non-aromatic and non-halogenated solvents are employed as protective agents to build SD devices with a configuration of indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS Clevios P VP Al 4083)/donor/protective solvent/acceptor/perylene diimide functionalized with amino N-oxide (PDINO)/Al, which shows that n-octane is the optimal choice for SD devices Nine different SD systems including the fullerene and nonfullerene ones present comparable photovoltaic performance to their BC counterparts, which proves the universality of this ESP method Significantly, the device of ITO/PEDOT:PSS/D18/N3/PDINO/Al with n-octane as the protective solvent achieves a maximum PCE of 1752%, which is the record efficiency of SD devices Furthermore, a protective factor (δ) is proposed to demonstrate the quantitative relationship between δ and PCE after experimental and theoretical investigation, which presents an idea to understand the mechanism and provides a guideline for solvent choices

66 citations


Journal ArticleDOI
TL;DR: Kohler et al. as mentioned in this paper proposed a passivating contact based on a double layer of nanocrystalline silicon carbide that overcomes the trade-offs of conductivity, defect passivation and optical transparency.
Abstract: A highly transparent passivating contact (TPC) as front contact for crystalline silicon (c-Si) solar cells could in principle combine high conductivity, excellent surface passivation and high optical transparency. However, the simultaneous optimization of these features remains challenging. Here, we present a TPC consisting of a silicon-oxide tunnel layer followed by two layers of hydrogenated nanocrystalline silicon carbide (nc-SiC:H(n)) deposited at different temperatures and a sputtered indium tin oxide (ITO) layer (c-Si(n)/SiO2/nc-SiC:H(n)/ITO). While the wide band gap of nc-SiC:H(n) ensures high optical transparency, the double layer design enables good passivation and high conductivity translating into an improved short-circuit current density (40.87 mA cm−2), fill factor (80.9%) and efficiency of 23.99 ± 0.29% (certified). Additionally, this contact avoids the need for additional hydrogenation or high-temperature postdeposition annealing steps. We investigate the passivation mechanism and working principle of the TPC and provide a loss analysis based on numerical simulations outlining pathways towards conversion efficiencies of 26%. Passivating contacts hold promise for silicon solar cells yet the simultaneous optimization of conductivity, defect passivation and optical transparency remains challenging. Now Kohler et al. devise a passivating contact based on a double layer of nanocrystalline silicon carbide that overcomes these trade-offs.

65 citations


Journal ArticleDOI
TL;DR: In this article, the bottom surface of active layers and interface of indium tin oxide (ITO) electrodes and active layers play a crucial role in determining the performance of polymer photodetectors with photomultiplication (PM-PPDs).
Abstract: Bottom surface of active layers and interface of indium tin oxide (ITO) electrodes and active layers play a crucial role in determining the performance of polymer photodetectors with photomultiplication (PM-PPDs). The interfacial trapped electron distribution closing to ITO electrodes will determine spectral response range and external quantum efficiency (EQE) of PMPPDs. The bottom interface is more sensitive than top interface when light is coming from the ITO side, and the larger density of generated charge on the bottom interfaces will induce interfacial band more bending for efficient charge tunneling injection. Highly sensitive and sub-microsecond PM-PPDs are achieved with PMBBDT:Y6 (100:7, w/w) as active layers under forward bias, yielding EQE of 18,700% at 320 nm, 21,700% at 600 nm and 16,400% at 810 nm under a bias of 7 V, respectively, as well as fast response time of 79 μs. The high EQE of the PM-PPDs is attributed to efficient hole tunneling injection from ITO electrode under forward bias. The electron traps closing to ITO electrode will be quickly filled up when light is coming from ITO side, leading to interfacial band more bending for hole tunneling injection. Importantly, the PM-PPDs is performed to measure heart rate (HR) and blood oxygen saturation (SpO2), and the measured data by the PM-PPDs are very similar with those obtained by commercial photodetectors.

63 citations


Journal ArticleDOI
TL;DR: In this paper, the indium-tin oxide glass (ITO/G) was used as a catalyst electrode for artificial N2 fixation, and the possible reaction mechanism for the NRR on the ITO catalysts was explored using first-principles calculations.

60 citations


Journal ArticleDOI
TL;DR: In this article, the pump dependent properties of the plasmon resonance in the ENZ region in a thin layer of indium tin oxide (ITO) were studied using the Kretschmann-Raether configuration.
Abstract: Nonlinear optical devices and their implementation into modern nanophotonic architectures are constrained by their usually moderate nonlinear response Recently, epsilon-near-zero (ENZ) materials have been found to have a strong optical nonlinearity, which can be enhanced through the use of cavities or nano-structuring Here, we study the pump dependent properties of the plasmon resonance in the ENZ region in a thin layer of indium tin oxide (ITO) Exciting this mode using the Kretschmann-Raether configuration, we study reflection switching properties of a 60 nm layer close to the resonant plasmon frequency We demonstrate a thermal switching mechanism, which results in a shift in the plasmon resonance frequency of 20 THz for a TM pump intensity of 70 GW cm−2 For degenerate pump and probe frequencies, we highlight an additional two-beam coupling contribution, not previously isolated in ENZ nonlinear optics studies, which leads to an overall pump induced change in reflection from 1% to 45% All-optical switching is important for integrated-photonics and communication devices Here the authors demonstrate all-optical switching of an Epsilon-Near-Zero plasmon resonance using indium tin oxide thin film

44 citations


Journal ArticleDOI
TL;DR: In this paper, the electrical and optical properties of indium tin oxide (ITO) films with different thicknesses were measured by the standard four-point probe method, showing that the measured electrical properties refer to a decrease in the sheet resistance Rs (Ω/sq) with the increase in the annealing temperature.

40 citations


Journal ArticleDOI
TL;DR: A manganese oxide nanoparticles based electrochemical immunosensor for the detection of Aflatoxin-B1 (AFB1) using purely synthesized Mn2O3nps with an average crystallite size of 31.5 nm is presented.

39 citations


Journal ArticleDOI
TL;DR: In this paper, a carbon electrode-based flexible perovskite solar cells (C-PSCs) with the structure of polyethylene terephthalate (PET)/graphene-silver nanowires were successfully prepared by low-temperature solution process.

38 citations


Journal ArticleDOI
TL;DR: In this article, a detailed improvement in the resistive switching behavior of Al-doped HfAlO-based resistive random access memory (RRAM) devices was studied by controlling the Al ratio during atomic layer deposition (ALD) on a transparent indium tin oxide (ITO) electrode.

34 citations


Journal ArticleDOI
TL;DR: In this article, the simultaneous determination of serotonin (5-HT) and melatonin (MT) by using highly ordered and vertically oriented mesoporous silica-nanochannel films (VMSF) on highly electrochemically reduced graphene oxide-carbon nanotubes (HErGO-CNT) composite substrate is reported.
Abstract: Herein we report the simultaneous determination of serotonin (5-HT) and melatonin (MT) by using highly ordered and vertically-oriented mesoporous silica-nanochannel films (VMSF) on highly electrochemically reduced graphene oxide-carbon nanotubes (HErGO-CNT) composite substrate. Such VMSF/HErGO-CNT with compact 2D-2D layered structure is fabricated on indium tin oxide (ITO) electrodes via a two-step electrochemical process, namely the electrodeposition of ErGO-CNT film onto the ITO surface by cyclic voltammetry and subsequently growth of VMSF on the ErGO-CNT/ITO surface by electrochemically assisted self-assembly method, during which graphene oxide (GO) is subjected to the two-time electrochemical reduction to form HErGO. The CNT encased in the GO sheets served as electronic conducting wires, which not only can promote the electrochemical reduction of GO but also contribute to a certain degree of hydrophobicity, facilitating the controllable electrodeposition of ErGO-CNT composites on ITO under its safe use potential window. In addition, doping CNT is able to enlarge the layer gap between graphene sheets and thus improves the electroactive area and mass transfer of the nanocarbon composite substrate. Furthermore, the underlying HErGO-CNT acts as an efficient electroactive layer and the outer VMSF possesses electrostatic preconcentration and anti-fouling functions, synergistically realizing the direct electrochemical analysis of 5-HT and MT in two complex biological fluids (human whole blood and artificial cerebrospinal fluid).

Journal ArticleDOI
TL;DR: In this article, a self-assembling COOH-functionalized P3HT (P3HT-COOH) is fabricated on which near crystal quality perovskite thin film can be grown.
Abstract: Crystallinity and crystal orientation have a predominant impact on a materials' semiconducting properties, thus it is essential to manipulate the microstructure arrangements for desired semiconducting device performance. Here, ultra-uniform hole-transporting material (HTM) by self-assembling COOH-functionalized P3HT (P3HT-COOH) is fabricated, on which near single crystal quality perovskite thin film can be grown. In particular, the self-assembly approach facilitates the P3HT-COOH molecules to form an ordered and homogeneous monolayer on top of the indium tin oxide (ITO) electrode facilitate the perovskite crystalline film growth with high quality and preferred orientations. After detailed spectroscopy and device characterizations, it is found that the carboxylic acid anchoring groups can down-shift the work function and passivate the ITO surface, retarding the interface carrier recombination. As a result, the device made with the self-assembled HTM show high open-circuit voltage over 1.10 V and extend the lifetime over 4,300 h when storing at 30% relative humidity. Moreover, the cell works efficiently under much reduced light power, making it useful as power source under dim-light conditions. The demonstration suggests a new facile way of fabricating monolayer HTM for high efficiency perovskite devices, as well as the interconnecting layer needed for tandem cell.

Journal ArticleDOI
TL;DR: In this article, a highly sensitive and stable capsaicin sensor was developed from carbon dots synthesized from iota-carrageenan, which was grafted onto an indium tin oxide (ITO) substrate via a novel one-step thermal annealing process.
Abstract: In this work, a highly sensitive and stable capsaicin sensor was developed from carbon dots synthesized from iota-carrageenan. The carbon dots were grafted onto an indium tin oxide (ITO) substrate via a novel one-step thermal annealing process. This was used as an electrode for the electrochemical detection of capsaicin. The carbon dot-grafted ITO electrode was sensitive across a wide linear range from 0.05 to 500 μM, with a remarkably low detection limit of 5.4 nM. The electrode showed excellent recyclability over 450 cycles, suggesting that it was electrochemically stable and can be reused for several hundred times. It demonstrated good selectivity towards capsaicin in the presence of multiple interferences: d -(+)-glucose, citric acid, l -ascorbic acid, Na+, K+, Mg2+, Ca2+, Fe2+, and Cl−. A recovery test was performed using Cayenne pepper, Tabasco sauce, and Thai chili, yielding the recovery in the range 92–108 %. In addition to high sensitivity, stability, and selectivity, the sensor could produce the detection results within 5 min. The novel capsaicin sensor developed here has potential uses for quality control in the agricultural, food, and pharmaceutical sectors.

Journal ArticleDOI
TL;DR: In this paper, it was shown that phase separation can be obtained in nanocomposite ITO films by tuning their stoichiometry simply by varying the oxygen partial pressure during deposition of thermoelectric materials.

Journal ArticleDOI
TL;DR: In this article, an optically transparent microwave absorber based on a conformal broadband metamaterial is proposed, which shows high angular stability and high light transmittance with high absorption bandwidth.
Abstract: We put forward an optically transparent microwave absorber based on a conformal broadband metamaterial, which shows high angular stability. Our absorber is a double-layer sandwich structure mainly made of transparent polyvinyl chloride sheets and indium tin oxide films. To achieve wideband absorption and high angular stability, an impedance layer composed of square spiral elements is exploited to increase the absorption bandwidth. A compensation layer is then employed to address the mismatch between the impedance of the absorber and that of free space at high angular incidences. Experimental results show that a high light transmittance (69.4%), together with an adequate absorption bandwidth (85.7%) and angular stability (60 $^{\circ }$ ) may be achieved with planar and conformal configurations, including different curvatures.

Journal ArticleDOI
TL;DR: In this article, low-temperature atomic layer deposition (ALD)-processed indium-free tin dioxide (SnO2) films are applied to a poly(3-hexylthiophene):indene-C60 bisadduct-based OPV system.
Abstract: Indoor organic photovoltaics (OPVs) are currently being investigated for small-scale energy generation from artificial light sources to power small electronic devices. Despite recent progress in increasing the power conversion efficiency (PCE) of indoor OPVs, the widespread use of expensive indium tin oxide (ITO) as a transparent conducting electrode (TCE) leads to long energy payback times. This study provides a novel and comprehensive description of low-temperature atomic layer deposition (ALD)-processed indium-free tin dioxide (SnO2) films as inexpensive and efficient TCEs for indoor OPVs. These highly conformal and defect-free ALD-fabricated SnO2 films are applied to a poly(3-hexylthiophene):indene-C60 bisadduct-based OPV system. Under 1 sun illumination, an OPV with an SnO2 TCE exhibits limited operational capacity because of the high sheet resistance (~98 Ω sq−1) of the SnO2 layers. However, under a light-emitting diode (LED) lamp with a luminance of 1000 lx, the series resistance, which is related to the sheet resistance, has a marginal effect on the performance of the indoor OPV system, showing a PCE of 14.6 ± 0.3%. A reference OPV with an ITO TCE has a slightly lower PCE of 13.3 ± 0.8% under the same LED conditions. These results suggest that SnO2 TCEs can be efficient and cost-effective replacements for ITO TCEs in indoor OPV systems. Indium-free un-doped tin dioxide (SnO2) serves as a transparent conducting electrode for indoor organic photovoltaics (OPVs). SnO2 OPV systems demonstrate superior indoor performance compared with indium tin oxide (ITO)-based systems. SnO2-based OPV systems shows 14.6% efficiency under 1000 lx of LED illumination. Low-cost SnO2 can be a promising substitute for expensive ITOs in indoor OPV systems.

Journal ArticleDOI
01 Jul 2021
TL;DR: In this paper, polyaniline thin films were abstained by the potentiostatic deposition technique, applying a potential of +2 V vs. SCE for 90 s. The obtained electrodes were tested as pH sensors in the range from 2 to 8, showing good behavior, with a sensitivity of 62.3 mV/pH.
Abstract: Nowadays, we are assisting in the exceptional growth in research relating to the development of wearable devices for sweat analysis. Sweat is a biofluid that contains useful health information and allows a non-invasive, continuous and comfortable collection. For this reason, it is an excellent biofluid for the detection of different analytes. In this work, electrochemical sensors based on polyaniline thin films deposited on the flexible substrate polyethylene terephthalate coated with indium tin oxide were studied. Polyaniline thin films were abstained by the potentiostatic deposition technique, applying a potential of +2 V vs. SCE for 90 s. To improve the sensor performance, the electronic substrate was modified with reduced graphene oxide, obtained at a constant potential of −0.8 V vs. SCE for 200 s, and then polyaniline thin films were electrodeposited on top of the as-deposited substrate. All samples were characterized by XRD, SEM, EDS, static contact angle and FT-IR/ATR analysis to correlate the physical-chemical features with the performance of the sensors. The obtained electrodes were tested as pH sensors in the range from 2 to 8, showing good behavior, with a sensitivity of 62.3 mV/pH, very close to a Nernstian response, and a reproducibility of 3.8%. Interference tests, in the presence of competing ions, aimed to verify the selectivity, were also performed. Finally, a real sweat sample was collected, and the sweat pH was quantified with both the proposed sensor and a commercial pH meter, showing an excellent concordance.

Journal ArticleDOI
TL;DR: In this article, a cost effective method for preparing nanoporous MoO3 thin film from chemical reagents was presented, which reveals charge transport capability of MoO-3 structure for optoelectronic and energy storage devices.

Journal ArticleDOI
TL;DR: In this paper, the authors reported results of the studies related to the fabrication of thionine functionalized graphitic carbon nitride nanosheets based ultrasensing platform for food toxin (Aflatoxin B1, AfB1) detection.

Journal ArticleDOI
TL;DR: In this article, a combination of the muscovite substrate and the antiferroelectric PbZrO3 (PZO) is studied as a model system.

Journal ArticleDOI
TL;DR: In this article, a femtosecond Z-scan measurement technique was used to investigate the NLO absorption properties of indium tin oxide (ITO) films at two different wavelengths of 1030 and 1440 nm.
Abstract: Indium tin oxide (ITO) films have recently emerged as a new class of functional materials for nonlinear optical (NLO) devices due to their exotic properties around epsilon-near-zero (ENZ) wavelength. Here, we experimentally investigated and tailored the NLO absorption properties of ITO films. The NLO absorption response of ITO films is investigated by using the femtosecond Z-scan measurement technique at two different wavelengths of 1030 nm (out of ENZ region) and 1440 nm (within ENZ region). Interestingly, we observed conversion behavior from saturable absorption (SA) to reverse saturable absorption (RSA) at 1030 nm with the increasing incident laser intensity, whereas only SA behavior was observed at 1440 nm. We demonstrate that SA behavior was ascribed to ground-state free electrons bleaching in the conduction band, and RSA was attributed to three-photon absorption. Moreover, results reveal that ITO film shows more excellent SA performance at 1440 nm with a nonlinear absorption coefficient of ∼−23.2 cm/GW and a figure of merit of ∼1.22×10−16 esu·cm. Furthermore, we tailored the SA and RSA behaviors of ITO films at 1030 and 1440 nm wavelengths via post-annealing treatment. The modulatable NLO absorption was ascribed to the changing of free-carrier concentration in ITO films via annealing treatment. The experimental findings offered an inroad for researchers to tailor its NLO absorption properties by changing the free-carrier concentration through chemical modification such as annealing, oxidation, or defect implantation. The superior and tunable nonlinear optical response suggests that ITO film might be employed as a new class material with potential applications in novel optical switches or optical limiters to realize the all-optical information process.

Journal ArticleDOI
TL;DR: In this article, an optically transparent broadband metamaterial absorber (MA) containing an air layer and a water layer is proposed, which can absorb broadband microwave and reduce infrared radiation at the same time.

Journal ArticleDOI
TL;DR: In this article, a fully printed perovskite solar cells (PSCs) were fabricated in air with all constituent layers, except for electrodes, deposited by the blade coating technique.
Abstract: Fully printed perovskite solar cells (PSCs) were fabricated in air with all constituent layers, except for electrodes, deposited by the blade coating technique. The PSCs incorporated, for the first time, a nanometer-thick printed bathocuproine (BCP) hole blocking buffer using blade coating and deposited at relative humidity up to 50%. The PSCs with a p-i-n structure (glass/indium tin oxide (ITO)/poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS)/CH3NH3PbI3/[6,6]-phenyl-C61-butyric acid methyl ester (PCBM)/BCP/Ag) delivered a maximum power conversion efficiency (PCE) of 14.9% on an active area of 0.5 cm2 when measured under standard test conditions. The PSCs with a blade coated BCP delivered performance of 10% and 63% higher (in relative terms) than those incorporating a spin coated BCP or without any BCP film, respectively. The atomic force microscopy (AFM) showed that blade coated films were more homogeneous and acted also as a surface planarizer leading to a reduction of roughness which improved BCP/Ag interface lowering charge recombination. The demonstration of 15% efficient devices with all constituent layers, including nanometer-thick BCP (∼ 10 nm), deposited by blade coating in air, demonstrates a route for industrialization of this technology.

Journal ArticleDOI
TL;DR: In this paper, an optically transparent metamaterial composed of planar indium tin oxide (ITO) structures and low-loss glass substrates is proposed for microwave absorption.

Journal ArticleDOI
TL;DR: In this paper, the presence of Pd on Pd-N doped-G/ITO is confirmed with SEM-EDX mapping and Density functional theory (DFT) calculations are also carried out to better understand the interaction of the molecules on pd modified G (Pd-G) and Pd modified N-doped 3NG surfaces.

Journal ArticleDOI
Wendong Tian1, Fei Liang1, Dazhi Lu1, Haohai Yu1, Huaijin Zhang1 
TL;DR: In this paper, the real part of the annealed indium tin oxide (ITO) film was designed to reach zero around 1050 nm, matching with the central wavelength of an Yb-based fiber laser, and the internal driving electric field was extremely enhanced.
Abstract: High-harmonic generation in the ultraviolet region is promising for wireless technology used for communications and sensing. However, small high-order nonlinear coefficients prevent us from obtaining high conversion efficiency and functional photonic devices. Here, we show highly efficient ultraviolet harmonic generation extending to the fifth order directly from an epsilon-near-zero indium tin oxide (ITO) film. The real part of the annealed ITO films was designed to reach zero around 1050 nm, matching with the central wavelength of an Yb-based fiber laser, and the internal driving electric field was extremely enhanced. A high energy conversion efficiency of 10−4 and 10−6 for 257.5 nm (fourth-order) and 206 nm (fifth-order) ultraviolet harmonic generation was obtained, which is at least 2 orders of magnitude higher than early reports. Our results demonstrate a new route for overcoming the inefficiency problem and open up the possibilities of compact solid-state high-harmonic generation sources at nanoscale.

Journal ArticleDOI
Song Kyu Kang1, Dae Yun Kang1, Jae Wan Park1, Kyung Rock Son1, Tae Geun Kim1 
TL;DR: In this paper, a Ni-doped ZnO/Ag/ZnO (Ni:ZAZ) electrode was used as an effective hole injection electrode for organic light-emitting diodes (OLEDs).

Journal ArticleDOI
TL;DR: In this article, the authors reported a novel approach to print high performance indium tin oxide (ITO)-based TFTs and logic inverters by taking advantage of the notorious coffee-ring effect.
Abstract: Metal oxide thin-films transistors (TFTs) produced from solution-based printing techniques can lead to large-area electronics with low cost. However, the performance of current printed devices is inferior to those from vacuum-based methods due to poor film uniformity induced by the “coffee-ring” effect. Here, we report a novel approach to print high-performance indium tin oxide (ITO)-based TFTs and logic inverters by taking advantage of such notorious effect. ITO has high electrical conductivity and is generally used as an electrode material. However, by reducing the film thickness down to nanometers scale, the carrier concentration of ITO can be effectively reduced to enable new applications as active channels in transistors. The ultrathin (~10-nm-thick) ITO film in the center of the coffee-ring worked as semiconducting channels, while the thick ITO ridges (>18-nm-thick) served as the contact electrodes. The fully inkjet-printed ITO TFTs exhibited a high saturation mobility of 34.9 cm2 V−1 s−1 and a low subthreshold swing of 105 mV dec−1. In addition, the devices exhibited excellent electrical stability under positive bias illumination stress (PBIS, ΔVth = 0.31 V) and negative bias illuminaiton stress (NBIS, ΔVth = −0.29 V) after 10,000 s voltage bias tests. More remarkably, fully printed n-type metal–oxide–semiconductor (NMOS) inverter based on ITO TFTs exhibited an extremely high gain of 181 at a low-supply voltage of 3 V, promising for advanced electronics applications.

Journal ArticleDOI
TL;DR: In this paper, the authors demonstrate broadband terahertz emission via surface optical rectification from a simple, commercially available 19nm-thick indium tin oxide (ITO) thin film.
Abstract: Broadband light sources emitting in the terahertz spectral range are highly desired for applications such as noninvasive imaging and spectroscopy. Conventionally, THz pulses are generated by optical rectification in bulk nonlinear crystals with millimetre thickness, with the bandwidth limited by the phase-matching condition. Here we demonstrate broadband THz emission via surface optical rectification from a simple, commercially available 19 nm-thick indium tin oxide (ITO) thin film. We show an enhancement of the generated THz signal when the pump laser is tuned around the epsilon-near-zero (ENZ) region of ITO due to the pump laser field enhancement associated with the ENZ effect. The bandwidth of the THz signal generated from the ITO film can be over 3 THz, unrestricted by the phase-matching condition. This work offers a new possibility for broadband THz generation in a subwavelength thin film made of an ENZ material, with emerging physics not found in existing nonlinear crystals. A new method for generating terahertz waves exploits the low-permittivity properties of an ultrathin film. Terahertz radiation, falling between the infrared and microwave range, has emerging applications in imaging, communications and materials inspection, and is usually generated through the rectification of optical signals in nonlinear crystals. Yuanmu Yang at Tsinghua University in Beijing and co-workers tried an alternative approach, directing a near-infrared laser onto commercially available films of indium tin oxide just 19 nanometres thick. They observed a large enhancement in the terahertz generation when they tuned the laser to hit the film’s ‘epsilon-near-zero’ state—a point where the permittivity of the thin film becomes vanishingly small. The method is relatively inefficient, but the researchers suggest that it could be enhanced by using other thin films in conjunction with metamaterials.

Journal ArticleDOI
TL;DR: A comprehensive review about the most recent developments in indium tin oxide (ITO) based electrochemical chemosensors and biosensors is presented in this article, where the main focus is on the sensor applications and properties of modified ITO electrodes in the determination of some biomarkers, pathogens, pesticides, drugs, organic species, and metals.
Abstract: This paper represents a comprehensive review about the most recent developments in indium tin oxide (ITO) based electrochemical chemosensors and biosensors. ITO electrode has received increasing attention due to its large potential window and excellent optical properties. It provides electrochemical stability and a low background current and has recently been applied as a working electrode in the electrochemical analysis. The focal point of this paper was based on the sensor applications and properties of modified ITO electrodes in the determination of some biomarkers, pathogens, pesticides, drugs, organic species, and metals, etc. by electrochemical techniques. Experimental conditions and some analytical parameters of the electrode applications were discussed. The future possibilities and prospects of ITO electrodes have been outlined. In this case, there are significant studies to display the powerful ITO sensors for the determination of analytes and this review summarizes the available data on this topic between 2010 and 2021.