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This study focused on enhancing the electrical conductivity of metal oxide nanosheet films by increasing the size of the nanosheets to promote the electron flow in the desired in-plane direction. We developed a method for increasing the size of RuO 2 metal oxide nanosheets, a 2D material, by controlling the heat-treatment process. The size of the RuO 2 nanosheets increased from 0.7 to 3.5 μm by modifying the heat-treatment conditions of K x RuO 2 , which was used as the precursor material. As a consequence, the electrical conductivity of the large-sized-RuO 2 nanosheet-coated films was eight times higher than that of their small-sized counterparts. This lower resistance was attributed to the minimal number of contacts required for electron flow; the contact resistance between the nanosheets being higher than the intrinsic resistance. The proposed approach for enhancing the conductivity of metal oxide 2D materials is very promising and is expected to significantly contribute to the development of advanced flexible electronic devices. [Display omitted] • Enlarged RuO 2 nanosheets boost electrical conductivity in flexible devices. • Controlled heat treatment of K x RuO 2 precursor material enhances nanosheet size. • Eightfold increase in electrical conductivity observed in larger nanosheets. • Reduced resistance due to minimized electron flow contacts in nanosheet films. • Promising method for improving electrical properties in flexible electronics. [ABSTRACT FROM AUTHOR]

The relation between the structure of the silver network electrodes and the properties of Cu(In,Ga)Se2 (CIGS) solar cells is systemically investigated. The Ag network electrode is deposited onto an Al:ZnO (AZO) thin film, employing a self‐forming cracked template. Precise control over the cracked template's structure is achieved through careful adjustment of temperature and humidity. The Ag network electrodes with different coverage areas and network densities are systemically applied to the CIGS solar cells. It is revealed that predominant fill factor (FF) is influenced by the figure of merit of transparent conducting electrodes, rather than sheet resistance, particularly when the coverage area falls within the range of 1.3–5%. Furthermore, a higher network density corresponds to an enhanced FF when the coverage areas of the Ag networks are similar. When utilizing a thinner AZO film, CIGS solar cells with a surface area of 1.0609 cm2 exhibit a notable performance improvement, with efficiency increasing from 10.48% to 11.63%. This enhancement is primarily attributed to the increase in FF from 45% to 65%. These findings underscore the considerable potential for reducing the thickness of the transparent conductive oxide (TCO) in CIGS modules with implications for practical applications in photovoltaic technology. [ABSTRACT FROM AUTHOR]

Silver nanowire networks are a promising replacement to indium tin oxide as transparent electrodes, which are necessary components of electrochromic devices. However, silver nanowires suffer from a short lifetime due to silver corrosion. Unlike many nanowire electrode passivation materials studied in the literature, the current work focuses on an inexpensive nonconductive passivation layer, allowing the utilization of transparent polymers. Herein, a coating of a thin layer of polyurethane (PU) was used to prevent corrosion and to limit the electrode sheet resistance to an increase of only 1.8× after 6 months. PU is cheap and easy to deposit, 96% transparent across the visible and NIR regions (Atkinson, J. "Silver Nanowire Networks in Electrochromic Devices", Thesis, University of Waterloo, Waterloo, 2023), increases the mechanical flexibility of nanowire electrodes, improves nanowire adhesion, and decreases surface roughness by an average of 15 nm. The PU-passivated nanowire electrodes are integrated into mechanically flexible symmetric PEDOT:PSS-based electrochromic displays. Compared to similar devices based on ITO electrodes, the PU-passivated nanowire-based devices show higher color modulation, shorter switching times, a larger change in reflectance in the visible properties, and a longer lifetime. Most noteworthy are their far superior mechanical properties. After 50 bending cycles, the nanowire-based devices had little change in performance, whereas ITO-based devices no longer worked. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission. [ABSTRACT FROM AUTHOR]

This study focused on enhancing the electrical conductivity of metal oxide nanosheet films by increasing the size of the nanosheets to promote the electron flow in the desired in-plane direction. We developed a method for increasing the size of RuO2 metal oxide nanosheets, a 2D material, by controlling the heat-treatment process. The size of the RuO2 nanosheets increased from 0.7 to 3.5 μm by modifying the heat-treatment conditions of KxRuO2, which was used as the precursor material. As a consequence, the electrical conductivity of the large-sized-RuO2 nanosheet-coated films was eight times higher than that of their small-sized counterparts. This lower resistance was attributed to the minimal number of contacts required for electron flow; the contact resistance between the nanosheets being higher than the intrinsic resistance. The proposed approach for enhancing the conductivity of metal oxide 2D materials is very promising and is expected to significantly contribute to the development of advanced flexible electronic devices.

Abstract Silver nanowires (AgNWs) have excellent flexibility, unique optical transmittance and high conductivity. The polyol process is appropriate for preparing AgNWs due to its simplicity, effectiveness, low cost, and high yield. This work aims to investigate the effect of preparation parameters of the polyol process on the silver nanowires properties. The parameters include the controlling agent, molecular weight of the polyvinylpyrrolidone (PVP), the temperature, and the reducing agent. The amount of silver nanoparticles formed during preparation was used to determine the optimum preparation conditions. The transmission electron microscope (TEM) images showed minimal amount of Ag nanoparticles when using mixed molecular weight of PVP-40K, and PVP-1.3M at 150 °C with the assistance of copper chloride as a controlling agent. The prepared AgNWs had an average length of 3.7 µm and aspect ratio of 15.3. The fabricated electrodes were characterized using a scanning electron microscope (SEM) and four probe resistivity measurements. The electrical measurement of the AgNWs electrodes indicated that the surfactant thickness is a critical parameter in having low sheet resistance electrodes. Also, the optical transmission was affected by the amount of nanoparticles. The prepared electrode with high concentration of AgNWs and a minimal amount of nanoparticles exhibited 80% optical transmission.

Transparent top electrodes are crucial for enhancing the performance of semitransparent organic solar cells (ST‐OSCs). The commonly evaporated ultra‐thin silver (Ag) electrode in ST‐OSCs suffers from limited transparency and conductivity due to its island‐like growth, posing a challenge in achieving desired conductivity and low optical loss. Here, a novel composite film is prepared by doping a small amount of samarium (Sm) into Ag during evaporation. The incorporation of Sm facilitates to form a continuous ultra‐thin Ag film by suppressing isolated island growth. A 15 nm Sm:Ag composite film with an optimized mass ratio of 1:30 exhibits a sheet resistance of 6 Ω □−1 and an average visible transmittance (AVT) of 66%, much better than 20 Ω □−1 and 43% of the pure Ag analogue. By employing the Sm:Ag electrode with an optical coupling layer, the ST‐OSCs demonstrate a power conversion efficiency of 10.89% and an AVT of 37.1%, resulting in a light utilization efficiency of 4.04%. Moreover, the resultant ST‐OSCs demonstrate superior color neutrality with a color rendering index of 91.9, representing one of the highest values among the ST‐OSCs with LUE exceeding 4% reported to date. This work provides a novel transparent top electrode with superior conductivity and transmittance for ST‐OSCs. [ABSTRACT FROM AUTHOR]

In the dynamic field of photovoltaic technology, the pursuit of efficiency and sustainability has led to continuous novelty, shaping the landscape of solar energy solutions. One of the key elements affecting the efficiency of photovoltaic cells of IInd and IIIrd generation is the presence of transparent conductive oxide (TCO) layers, which are key elements impacting the efficiency and durability of solar panels, especially for DSSC, CdTe, CIGS (copper indium gallium diselenide) or organic, perovskite and quantum dots. TCO with low electrical resistance, high mobility, and high transmittance in the VIS–NIR region is particularly important in DSSC, CIGS, and CdTe solar cells, working as a window and electron transporting layer. This layer must form an ohmic contact with the adjacent layers, typically the buffer layer (such as CdS or ZnS), to ensure efficient charge collection Furthermore it ensures protection against oxidation and moisture, which is especially important when transporting the active cell structure to further process steps such as lamination, which ensures the final seal. Transparent conductive oxide layers, which typically consist of materials such as indium tin oxide (ITO) or alternatives such as fluorine-doped tin oxide (FTO), serve dual purposes in photovoltaic applications. Primarily located as the topmost layer of solar cells, TCOs play a key role in transmitting sunlight while facilitating the efficient collection and transport of generated electrical charges. This complex balance between transparency and conductivity highlights the strategic importance of TCO layers in maximizing the performance and durability of photovoltaic systems. As the global demand for clean energy increases and the photovoltaic industry rapidly develops, understanding the differential contribution of TCO layers becomes particularly important in the context of using PV modules as building-integrated elements (BIPV). The use of transparent or semi-transparent modules allows the use of building glazing, including windows and skylights. In addition, considering the dominant position of the Asian market in the production of cells and modules based on silicon, the European market is intensifying work aimed at finding a competitive PV technology. In this context, thin-film, organic modules may prove competitive. For this purpose, in this work, we focused on the electrical parameters of two different thicknesses of a transparent FTO layer. First, the influence of the FTO layer thickness on the transmittance over a wide range was verified. Next, the chemical composition was determined, and key electrical parameters, including carrier mobility, resistivity, and the Hall coefficient, were determined. [ABSTRACT FROM AUTHOR]

Multilayer structures based on the In‐Zn‐O (IZO) system with modulated oxygen doping have been developed as a TCF (transparent conductive film) alternative to ITO or IGZO layers in the LC and OLED displays. The minimum resistivity (3.37 Ohm*cm) and the maximum concentration of free charge carriers correspond to the layers synthesized in an atmosphere of pure argon, while the maximum mobility (39.18 cm2/V*s) corresponds to the layers synthesized in the atmosphere of both argon and oxygen 99.6%/0.4% mixture. Thin‐film periodic structures with gradient modulation of oxygen content in thickness have been fabricated by periodically changing the oxygen concentration in the composition of the working gas during spraying at a substrate temperature of 100 °C. The structures consist of alternating layers with a high concentration of free charge carriers and layers with high mobility. As a result of the single layers' thicknesses optimization the thin‐film periodic structures with a minimum resistivity of 2.89 Ohm*cm have been made. The resistivity is lower than in homogeneous layers of the same composition. The alternation of layers of optimal thickness provides high carrier mobility, it is inherent to layers synthesized in the atmosphere of 99.6/0.4 argon and oxygen mixture at high concentration. The mobility value is close to the value achieved in the layers synthesized in the pure argon atmosphere. This material provides fabrication of high quality, stable and low cost transparent electrodes or TFT layers with performances corresponding to parameters of traditional materials. [ABSTRACT FROM AUTHOR]

This study fabricated a functional coating layer for transparent electrodes using antimony tin oxide nanopowder. The wet grinding method was employed to create a stable dispersion solution of antimony tin oxide nanopowder with aminopropyl tri-methoxysilane and acetyl acetone as primary dispersing agents. Various concentrations of these dispersing agents were used to determine optimal conditions, followed by a gel reaction to form a stable solution. The primary objective was to provide a viable alternative to indium-based transparent electrodes, specifically indium tin oxide, by incorporating antimony oxide. This approach not only addresses limitations associated with indium, but also enhances mechanical properties. The methodology involves the utilization of antimony tin oxide nanopowder and various solvents including ethanol and aforementioned dispersing agents to create a stable antimony tin oxide sol through wet grinding. Effects of dispersant concentration and milling time on the secondary particle size of the antimony tin oxide sol were thoroughly evaluated. Furthermore, this study examined sheet resistance of resulting coating layers by conducting a comparative analysis between antimony tin oxide and indium tin oxide under similar conditions. Findings of this study meticulously detailed in subsequent sections of the manuscript provide valuable insights into optimizing the entire process, encompassing synthesis, coating, heat treatment, and the production of high-quality transparent conductive coatings. These techniques and outcomes can significantly contribute to the development of more sustainable and cost-effective alternatives to traditional indium-based transparent electrodes.

In academic research, OLEDs have exhibited rapid evolution thanks to the development of innovative materials, new device architectures, and optimized fabrication methods, achieving high performance in recent years. The numerous advantages that increasingly distinguish them from traditional light sources, such as a large and customizable emission area, color tunability, flexibility, and transparency, have positioned them as a promising candidate for various applications in the lighting market, including the residential, automotive, industrial, and agricultural sectors. However, despite these promising attributes, the widespread industrial production of OLEDs encounters significant challenges. Key considerations center around efficiency and lifetime. In the present review, after introducing the theoretical basis of OLEDs and summarizing the main performance developments in the industrial field, three crucial aspects enabling OLEDs to establish a competitive advantage in terms of performance and versatility are critically discussed: the quality and stability of the emitted light, with a specific focus on white light and its tunability; the transparency of both electrodes for the development of fully transparent and integrable devices; and the uniformity of emission over a large area. [ABSTRACT FROM AUTHOR]

Introduction: We examined how pulse train electrical stimulation of the inner surface of the rabbit retina effected the resident glial cells. We used a rabbit retinal eyecup preparation model, transparent stimulus electrodes, and optical coherence tomography (OCT). The endfeet of Müller glia processes line the inner limiting membrane (ILM). Methods: To examine how epiretinal electrode stimulation affected the Müller glia, we labeled them post stimulation using antibodies against soluble glutamine synthetase (GS). After 5 min 50 Hz pulse train stimulation 30 µm from the surface, the retina was fixed, immunostained for Müller glia, and examined using confocal microscopic reconstruction. Stimulus pulse charge densities between 133-749 µC/cm2/ph were examined. Results: High charge density stimulation (442-749 µC/cm2/ph) caused significant losses in the GS immunofluorescence of the Müller glia endfeet under the electrode. This loss of immunofluorescence was correlated with stimuli causing ILM detachment when measured using OCT. Müller cells show potassium conductances at rest that are blocked by barium ions. Using 30 msec 20 µA stimulus current pulses across the eyecup, the change in transretinal resistance was examined by adding barium to the Ringer. Barium caused little change in the transretinal resistance, suggesting under low charge density stimulus pulse conditions, the Müller cell radial conductance pathway for these stimulus currents was small. To examine how epiretinal electrode stimulation affected the microglia, we used lectin staining 0-4 h post stimulation. After stimulation at high charge densities 749 µC/cm2/ph, the microglia under the electrode appeared rounded, while the local microglia outside the electrode responded to the stimulated retina by process orientation inwards in a ring by 30 min post stimulation. Discussion: Our study of glial cells in a rabbit eyecup model using transparent electrode imaging suggests that epiretinal electrical stimulation at high pulse charge densities, can injure the Müller and microglia cells lining the inner retinal surface in addition to ganglion cells. [ABSTRACT FROM AUTHOR]

Abstract—Since the stability of functional properties of a transparent conducting three-layer structure ZnO:Ga/Ag/ZnO:Ga is important for practical application, we studied its long-term durability and thermal stability in air environment. It has been demonstrated that after prolonged interaction with the air environment at room temperature (for ~1000 days) and further heat treatment in air at temperatures of up to 450°C (for up to 10 h), the three-layer structure retains its integrity and is characterized by a low sheet resistance Rs = 2.8 Ohm/sq at average transmittance in the visible range Tav = 82.1%. [ABSTRACT FROM AUTHOR]

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS), a conductive polymer, is one of the candidate materials for stretchable, transparent electrodes in wearable optoelectronic devices. The treatment of PEDOT:PSS films with organic solvents, e.g., methanol in this study, and acids improves the sheet conductance of the polymer film. This study presents a fabrication process to maximize the conductance of the PEDOT:PSS film, by optimizing the methanol treatment method. Two treatment methods, post-treatment and in-situ treatment, are compared. The in-situ treatment at the optimal methanol concentration is found to be slightly more effective than the post-treatment in reducing the resistance of the PEDOT:PSS films. Forming multilayers of the PEDOT:PSS film further reduces the sheet resistance. However, the multilayer structure also decreases the optical transmittance, which is undesirable in optoelectronic applications. As a result, two layers of the PEDOT:PSS film are selected as an optimal number of layers in terms of conductance and transmittance. The double-layered PEDOT:PSS film coated on a stretchable polydimethylsiloxane (PDMS) substrate demonstrates stable strain-dependent resistance up to 100% strain. Finally, the stretchable PEDOT:PSS electrode fabricated by the optimized process was used as the transparent electrode for a perovskite solar cell, exhibiting typical J−V characteristics with a power conversion efficiency of 1.65%. [ABSTRACT FROM AUTHOR]

Free-form factor optoelectronics is becoming more important for various applications. Specifically, flexible and transparent optoelectronics offers the potential to be adopted in wearable devices in displays, solar cells, or biomedical applications. However, current transparent electrodes are limited in conductivity and flexibility. This study aims to address these challenges and explore potential solutions. For the next-generation transparent conductive electrode, Al-doped zinc oxide (AZO) and silver (AZO/Ag/AZO) deposited by in-line magnetron sputtering without thermal treatment was investigated, and this transparent electrode was used as a transparent organic light-emitting diode (OLED) anode to maximize the transparency characteristics. The experiment and simulation involved adjusting the thickness of Ag and AZO and OLED structure to enhance the transmittance and device performance. The AZO/Ag/AZO with Ag of 12 nm and AZO of 32 nm thickness achieved the results of the highest figure of merit (FOM) (Φ550 = 4.65 mΩ−1) and lowest roughness. The full structure of transparent OLED (TrOLED) with AZO/Ag/AZO anode and Mg:Ag cathode reached 64.84% transmittance at 550 nm, and 300 cd/m2 at about 4 V. The results demonstrate the feasibility of adopting flexible substrates, such as PET, without the need for thermal treatment. This research provides valuable insights into the development of transparent and flexible electronic devices. [ABSTRACT FROM AUTHOR]

Dye-sensitized solar cells (DSSCs) are low-cost solar energy conversion devices with variable color and transparency advantages. DSSCs' potential power efficiency output, even in diffuse light conditions with consistent performance, allows them to be used in building-integrated photovoltaics (BIPV) window applications. Significantly, the development of bifacial DSSCs is getting significant scientific consideration. Triiodide/iodide (I3–/I–) redox couple-mediated DSSCs require highly effective and stable electrocatalysts for I3− reduction to overcome their performance constraints. However, the commonly employed platinum (Pt) cathodes have restrictions on high price and unfavorable durability. Here, we report platinum nanoparticles (Pt NPs) incorporated into multiwalled carbon nanotubes (MWCNT) composites with lower Pt content as an efficient bifacial counter electrode (CE) material for DSSC applications. Pt NPs were homogenously decorated over the MWCNT surfaces using a simple polyol method at relatively low temperatures. CEs fabricated using Pt/MWCNT composites exhibited excellent transparency and power conversion efficiencies (PCE) of 6.92% and 6.09% for front and rear illumination. The results are expected to bring significant advances in bifacial DSSCs for real-world window applications. [ABSTRACT FROM AUTHOR]

Abstract Dye-sensitized solar cells (DSSCs) are low-cost solar energy conversion devices with variable color and transparency advantages. DSSCs' potential power efficiency output, even in diffuse light conditions with consistent performance, allows them to be used in building-integrated photovoltaics (BIPV) window applications. Significantly, the development of bifacial DSSCs is getting significant scientific consideration. Triiodide/iodide (I3 –/I–) redox couple-mediated DSSCs require highly effective and stable electrocatalysts for I3 − reduction to overcome their performance constraints. However, the commonly employed platinum (Pt) cathodes have restrictions on high price and unfavorable durability. Here, we report platinum nanoparticles (Pt NPs) incorporated into multiwalled carbon nanotubes (MWCNT) composites with lower Pt content as an efficient bifacial counter electrode (CE) material for DSSC applications. Pt NPs were homogenously decorated over the MWCNT surfaces using a simple polyol method at relatively low temperatures. CEs fabricated using Pt/MWCNT composites exhibited excellent transparency and power conversion efficiencies (PCE) of 6.92% and 6.09% for front and rear illumination. The results are expected to bring significant advances in bifacial DSSCs for real-world window applications.

In the dynamic field of photovoltaic technology, the pursuit of efficiency and sustainability has led to continuous novelty, shaping the landscape of solar energy solutions. One of the key elements affecting the efficiency of photovoltaic cells of IInd and IIIrd generation is the presence of transparent conductive oxide (TCO) layers, which are key elements impacting the efficiency and durability of solar panels, especially for DSSC, CdTe, CIGS (copper indium gallium diselenide) or organic, perovskite and quantum dots. TCO with low electrical resistance, high mobility, and high transmittance in the VIS–NIR region is particularly important in DSSC, CIGS, and CdTe solar cells, working as a window and electron transporting layer. This layer must form an ohmic contact with the adjacent layers, typically the buffer layer (such as CdS or ZnS), to ensure efficient charge collection Furthermore it ensures protection against oxidation and moisture, which is especially important when transporting the active cell structure to further process steps such as lamination, which ensures the final seal. Transparent conductive oxide layers, which typically consist of materials such as indium tin oxide (ITO) or alternatives such as fluorine-doped tin oxide (FTO), serve dual purposes in photovoltaic applications. Primarily located as the topmost layer of solar cells, TCOs play a key role in transmitting sunlight while facilitating the efficient collection and transport of generated electrical charges. This complex balance between transparency and conductivity highlights the strategic importance of TCO layers in maximizing the performance and durability of photovoltaic systems. As the global demand for clean energy increases and the photovoltaic industry rapidly develops, understanding the differential contribution of TCO layers becomes particularly important in the context of using PV modules as building-integrated elements (BIPV). The use of transparent or semi-transparent modules allows the use of building glazing, including windows and skylights. In addition, considering the dominant position of the Asian market in the production of cells and modules based on silicon, the European market is intensifying work aimed at finding a competitive PV technology. In this context, thin-film, organic modules may prove competitive. For this purpose, in this work, we focused on the electrical parameters of two different thicknesses of a transparent FTO layer. First, the influence of the FTO layer thickness on the transmittance over a wide range was verified. Next, the chemical composition was determined, and key electrical parameters, including carrier mobility, resistivity, and the Hall coefficient, were determined.

Graphene-based flexible transparent electrodes (FTEs) are promising candidate materials for developing next-generation flexible organic light-emitting diodes (OLEDs). However, the quest for high-efficiency OLEDs is hindered by the low light-extraction and charge injection efficiencies of graphene electrode. Here, we combine the frustrated Lewis pair doping with nanostructure engineering to obtain high-performance graphene FTE. A p-type dopant aci-nitromethane-tris(pentafluorophenyl) borane (ANBCF) was synthesized and deposited on graphene FTE to form an aperiodic nanostructure, which not only improves the light-extraction but also stably p-dopes graphene to enhance its hole injection. The use of ANBCF-doped graphene as the anode enables high-efficiency flexible green OLEDs with external quantum efficiency (EQE) and power efficiency (PE) out-performing most flexible graphene OLEDs of comparable structure. This study provides a simple and effective pathway to fabricate highperformance graphene FTEs for efficient flexible OLEDs. [ABSTRACT FROM AUTHOR]

Perovskite/silicon tandem solar cells show great potential for commercialization because of their high power conversion efficiency (PCE). The optical loss originated from the transparent electrode is still a challenge to further improve the PCE of perovskite/silicon tandem solar cells. Here, we developed zirconium‐doped indium oxide (IZrO), a material with low resistivity and high transmittance sputtered at room temperature. It possesses a high mobility of 29.6 cm2/(V·s), a low resistivity of 3.32 × 10−4 Ω·cm, and a low sheet resistance of 25.55 Ω·sq−1 as well as a high average transmittance of 81.55% in a broadband of 400–1200 nm. Moreover, the work function (WF = 4.33 eV) matches well with the energy level of Ag electrode and SnO2 buffer layer in the P‐I‐N type tandem device. Compared with the previous zinc‐doped indium oxide (IZO) transparent electrode device, the absolute efficiency of perovskite/silicon tandem devices based on IZrO electrode is about 0.6% higher. The champion P‐I‐N type perovskite/silicon tandem solar cells employing IZrO as the front conducts show efficiency of 28.28% (area of 0.5036 cm2). [ABSTRACT FROM AUTHOR]

Currently semiconductor-based near ultraviolet and ultraviolet self-powered photodetectors usually display low detectivity and responsivity due to weak photogenerated electron and hole separation ability and not suitable electrode. BaTiO 3 possesses a high depolarization electric field throughout the bulk and wide band gap (> 3 eV), and hence is a good candidate for fabricating near-ultraviolet and ultraviolet self-powered photodetectors. Cu nanowires (NWs) have been regarded as promising transparent electrode for photodetectors because they have not only equivalent optical transparency and electrical conductivity relative to Ag NWs currently in use, but also far lower cost. But, weak resistance to oxidation in the environment of light and electricity prevents large-scale use of Cu NWs in photodetectors. Herein, an organic corrosion inhibitor, benzotriazole (BTA), is used to passivate Cu NWs, and interestingly, the passivated NW networks exhibit significantly increased resistance to oxidation. At zero field, the BaTiO 3 photodetector coated with Cu@BTA NWs exhibits stable photocurrent, high responsibility of 6.45 × 10−7A/W, large detectivity of 1.97 × 108 Jones, and fast response rate (rise and decay time being 28.8 ms and 37.2 ms, respectively) at the wavelength of 405 nm, which is far better than indium-tin-oxide electrode-coated BaTiO 3 photodetector. This work provides a strong guideline for large-scale fabrication of low-cost and high-stability transparent electrodes applicable in near-ultraviolet and ultraviolet photoelectric devices. [ABSTRACT FROM AUTHOR]

Abstract As an organic cation, quaternary ammonium salt was introduced as a control agent to synthesize silver nanowires. The important influence of quaternary ammonium salt on the preparation of silver nanowires was seriously investigated by varying the length of carbon chain and its amount. Results showed that using quaternary ammonium salt as the control agent can successfully control the growth of silver nanowires, of which the diameters ranging from 35.06 to 46.60 nm. The diameters of the as‐prepared silver nanowires tended to be smaller with a longer carbon chain. This work provides a new aspect for controllable preparation of silver nanowires. Furthermore, the as‐prepared silver nanowires were used to prepare transparent electrodes. They exhibited good optical performance with 95.6% transmittance at a low sheet resistance of 18 Ω/square, demonstrating their great potential in the application for touch screens.

Herein, semi-transparent polymer light-emitting diodes (PLEDs) are demonstrated by introducing a vacuum-free and dry-transferable conducting polymer (CP) transparent electrode (TE) which can replace opaque and vacuum-processed metal top electrodes. The CP films with outstanding TE performance, prepared on polydimethylsiloxane stamps via solution processing, can be directly transferred as top TEs onto underlying interfacial layers. The resulting semi-transparent PLEDs with indium-tin-oxide bottom TE and CP top TE provide a good semi-transparency and decent electroluminescence performance with good color coordinate through top emission. This work would be expected to offer a new way of realizing next-generation (semi-)transparent displays in a cost-effective way. [ABSTRACT FROM AUTHOR]

It is common knowledge that using different oxygen contents in the working gas during sputtering deposition results in fabrication of indium zinc oxide (IZO) films with a wide range of optoelectronic properties. It is also important that high deposition temperature is not required to achieve excellent transparent electrode quality in the IZO films. Modulation of the oxygen content in the working gas during RF sputtering of IZO ceramic targets was used to deposit IZO-based multilayers in which the ultrathin IZO unit layers with high electron mobility (μ-IZO) alternate with ones characterized by high concentration of free electrons (n-IZO). As a result of optimizing the thicknesses of each type of unit layer, low-temperature 400 nm thick IZO multilayers with excellent transparent electrode quality, indicated by the low sheet resistance (R ≤ 8 Ω/sq.) with high transmittance in the visible range ( T ¯ > 83%) and a very flat multilayer surface, were obtained. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNWs) have shown great potential in various optical and electronic applications, especially in flexible and wearable devices. Polyol method is now a mainstream strategy to synthesize AgNWs. However, unreacted reagents including silver salt, surfactant, and solvent are usually discarded after the collection of products, resulting in a huge waste as well as a burden to the environment. In this work, we demonstrate a simple recycle method to reuse these reagents based on a two-step direct centrifugation protocol. Larger nanowires are separated, while remaining small nanowires and nanoparticles provide nucleation sites and likely function as catalysts to achieve a three-times faster nanowire growth. The cyclic synthesis can maintain at least five consecutive rounds to produce AgNWs with similar size and yield and more rounds under suitable adjustment of Ag+ supply. Transparent conductive films based on AgNWs grown from recycled reagents show excellent and consistent optoelectronic performance, namely, a sheet resistance of 141.3 Ω/sq at a transmittance of 99.7% and 9.48 Ω/sq at 92.9%. A transparent heater with a PDMS/AgNWs/PET structure exhibits a resistance of 8.6 Ω at a total transmittance of 76.5% and is heated to 75.8 °C at a 3.5 V power supply. A fast-defrosting process is demonstrated. The recycling method significantly reduces the cost of AgNW production and may widen their application in high-performance flexible devices. [ABSTRACT FROM AUTHOR]

Free-form factor optoelectronics is becoming more important for various applications. Specifically, flexible and transparent optoelectronics offers the potential to be adopted in wearable devices in displays, solar cells, or biomedical applications. However, current transparent electrodes are limited in conductivity and flexibility. This study aims to address these challenges and explore potential solutions. For the next-generation transparent conductive electrode, Al-doped zinc oxide (AZO) and silver (AZO/Ag/AZO) deposited by in-line magnetron sputtering without thermal treatment was investigated, and this transparent electrode was used as a transparent organic light-emitting diode (OLED) anode to maximize the transparency characteristics. The experiment and simulation involved adjusting the thickness of Ag and AZO and OLED structure to enhance the transmittance and device performance. The AZO/Ag/AZO with Ag of 12 nm and AZO of 32 nm thickness achieved the results of the highest figure of merit (FOM) (Φ550 = 4.65 mΩ−1) and lowest roughness. The full structure of transparent OLED (TrOLED) with AZO/Ag/AZO anode and Mg:Ag cathode reached 64.84% transmittance at 550 nm, and 300 cd/m2 at about 4 V. The results demonstrate the feasibility of adopting flexible substrates, such as PET, without the need for thermal treatment. This research provides valuable insights into the development of transparent and flexible electronic devices.

Poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate) (PEDOT:PSS) is an important organic electrode for solution-processed low-cost electronic devices. However, it requires doping and post-solvent treatment to improve its conductivity, and the chemicals used for such treatments may affect the device fabrication process. In this study, we developed a novel route for exploiting ultrafast lasers (femtosecond and picosecond laser) to simultaneously enhance the conductivity and transparency of PEDOT:PSS films and fabricate patterned solution-processed electrodes for electronic devices. The conductivity of the PEDOT:PSS film was improved by three orders of magnitude (from 3.1 to 1024 S·cm–1), and high transparency of up to 88.5% (average visible transmittance, AVT) was achieved. Raman and depth-profiling X-ray photoelectron spectroscopy revealed that the oxidation level of PEDOT was enhanced, thereby increasing the carrier concentration. The surface PSS content also decreased, which is beneficial to the carrier mobility, resulting in significantly enhanced electrical conductivity. Further, we fabricated semitransparent perovskite solar cells using the as-made PEDOT:PSS as the transparent top electrodes, and a power conversion efficiency of 7.39% was achieved with 22.63% AVT. Thus, the proposed route for synthesizing conductive and transparent electrodes is promising for vacuum and doping-free electronics. [ABSTRACT FROM AUTHOR]

Transparent, flexible, and chemically stable conducting electrodes are the most important key components for fabricating optoelectronic devices. However, in conventional bulk metal–semiconductor (MS) junctions, Fermi-level pinning is a major concern that limits the charge transport properties of the devices. In this work, we have designed MS junctions using two-dimensional (2D) MXene nanosheets and Al-doped ZnO nanoparticles as a metal and an n-type semiconductor, respectively. The heterojunction was formed by layer-by-layer self-assembly on an indium tin oxide (ITO) substrate and probed by the Pt/Ir scanning tunneling microscopy (STM) tip at room temperature. By recording the tunneling current of the components that in turn yielded the density of states of the materials, we could identify their energy positions to determine the band alignments. We then proceeded to form heterojunctions and characterized their current–voltage characteristics through scanning tunneling spectroscopy. The junctions showed rectification, and the rectification ratio varied with the semiconductor doping concentrations. However, the shift of the Fermi level toward the conduction band edge of the semiconductor reduces the Schottky barrier width and consequently lowers the rectification ratio. Additionally, the MS junction with the poly-allylamine (PAH)-functionalized MXene nanosheets and the ZnO layer show a nonrectifying nature with low contact resistance at the interface. This work shows how a functionalized 2D-metal MXene and doped ZnO nanoparticle can tune the MS junction properties, used for implementing various flexible optoelectronic devices and transistor applications. [ABSTRACT FROM AUTHOR]

Metal grid transparent electrodes, as a key component in a variety of optoelectronic devices, are studied to maintain high electrical conductivity of electrode materials and enhanced light transmittance. In this work, Cu grid transparent electrode was successfully constructed by Cu nanodome-layer thin films. The Cu nanodome-layer thin film with a thickness of 1.32 μm was fabricated using facile and low-cost magnetron sputtering method. Because of the large thickness and long distance between two neighboring lines of the Cu grid transparent electrode, an enhanced sheet resistance of 14 Ω/□ was obtained, and the transmittance was broadened in the wavelength ranging from 318 to 900 nm. These results demonstrated that the method of tuning structure of materials will greatly enhance the efficiency and yield of micro-machining technology, which provides valuable information for the construction of various devices and domains. [ABSTRACT FROM AUTHOR]

The synthesis process of aluminum-doped zinc-oxide ceramics (ZnO : Al) from an initial mixture of commercial powders of zinc and aluminum oxides with a low specific surface area (no more than 5 m2/g) which consists in the preliminary formation of a slip and subsequent high-temperature sintering in an open atmosphere is studied. It is found that the porosity of the slip blank, density of sintered ceramics, and degree of predominant stacking of grains in it depend on both the duration of grinding of the slip and its pH index. It is demonstrated that, by optimizing the conditions of slip casting, obtaining conducting ZnO : Al ceramics with a density of more than 97% relative to the standard density of ZnO is possible, which is acceptable in the synthesis of ceramic targets intended for the formation of energy-saving thermal control coatings. [ABSTRACT FROM AUTHOR]

Silver nanowire (Ag NW)-based transparent back electrodes prepared via all solution-process are promising for bifacial and semitransparent perovskite solar cells (PSCs). However, the inadequate electrical contact between the silver nanowires themselves and the contact with substrate leads to reduced overall solar cell performance; meanwhile, serious corrosion of Ag NW in ambient environment restricting the further applications. In this work, polyvinylpyrrolidone (PVP) as a binder in Ag NW electrode significantly enhances the conductivity and transparency at the same time improving the interface electric contact. The PSC with PVP modified Ag NW electrode demonstrated frontside and backside efficiency approaching 18 % and 14.1 % (AM1.5, 1 Sun), respectively, which achieves 82 % efficiency with normal Ag device and bifacial factor of 79 %. The long-term storage stability of PSC is also improved by PVP protection. The final device structure is ITO/Ni O x /MeO/(FA0.92MA0.08)0.95Cs0.05Pb(I0.9Br0.1)3/PEAI/PC61BM/BCP/ Ag NW. This work highlights the method to fabricate robust transparent Ag NW electrode for bifacial perovskite solar cells. • Polyvinylpyrrolidone (PVP) in Ag nanowire (Ag NW) electrode significantly enhances the conductivity and transparency. • PVP modified Ag NW electrode improves the interface electric contact and charge transport of the solar cell. • The Perovskite solar cell (PSC) with PVP modified Ag NW electrode demonstrated high efficiency and bifacial factor. • The long-term storage stability of PSC is also improved by PVP protection. [ABSTRACT FROM AUTHOR]

Abstract In this study, we performed metal (Ag, Ni, Cu, or Pd) electroplating of core–shell metallic Ag nanowire (AgNW) networks intended for use as the anode electrode in organic light-emitting diodes (OLEDs) to modify the work function (WF) and conductivity of the AgNW networks. This low-cost and facile electroplating method enabled the precise deposition of metal onto the AgNW surface and at the nanowire (NW) junctions. AgNWs coated onto a transparent glass substrate were immersed in four different metal electroplating baths: those containing AgNO3 for Ag electroplating, NiSO4 for Ni electroplating, Cu2P2O7 for Cu electroplating, and PdCl2 for Pd electroplating. The solvated metal ions (Ag+, Ni2+, Cu2+, and Pd2+) in the respective electroplating baths were reduced to the corresponding metals on the AgNW surface in the galvanostatic mode under a constant electric current achieved by linear sweep voltammetry via an external circuit between the AgNW networks (cathode) and a Pt mesh (anode). The amount of electroplated metal was systematically controlled by varying the electroplating time. Scanning electron microscopy images showed that the four different metals (shells) were successfully electroplated on the AgNWs (core), and the nanosize-controlled electroplating process produced metal NWs with varying diameters, conductivities, optical transmittances, and WFs. The metal-electroplated AgNWs were successfully employed as the anode electrodes of the OLEDs. This facile and low-cost method of metal electroplating of AgNWs to increase their WFs and conductivities is a promising development for the fabrication of next-generation OLEDs.

Ag has the lowest electrical resistivity among all metals, and at the same time, the best optical properties in the visible and near-IR spectral range; it is therefore the most widely employed material for thin-metal-film-based transparent conductors. In this work, an ultra-thin transparent silver film electrode with aluminum as seed layer was prepared by a resistive thermal evaporation technique. Using a range of electrical, optical and surface morphology techniques, it can be noted that the presence of the thin layer of aluminum changes the growth kinetics (nucleation and evolution) of the thermal evaporation of Ag, leading to silver films with smooth surface morphology and high electrical conductivity, and the threshold thickness of the silver film is reduced. It is inferred that the aluminum layer showed a good infiltration effect on the ultra-thin silver film, by analyzing the transmittance spectrum, sheet resistance and surface morphology. Moreover, the average transmittance of silver film with 10 nm is 40% in the 400–2500 nm band, whereas the sheet resistance is 13 Ωsq −1. A series of experiments show that the introduction of Al seed layer has certain effect on improving the properties of transparent conductive silver films. Then, a new method for deposition of 1 nm Al seed layer was proposed; that is, the 1 nm aluminum infiltrated layer is divided into two or more layers, and the average transmittance of silver film with 5 nm is 60% in the 400–2500 nm band, whereas the sheet resistance does not exceed 100 Ω sq−1. [ABSTRACT FROM AUTHOR]

Electrodes in new function-flexible optoelectronic devices, need to meet the requirements of foldability and high transmittance. In last decades, thousands of research about copper and silver nanowires promoted the prosperity of photovoltaic industry. In this paper, we focus on the recent progresses of silver and copper nanowires for high transparent solar cell application, including preparation and optimization techniques. In addition, the primary obstacles of nanowire transparent electrodes in perovskite solar cells, organic solar cells and dye sensitized solar cells were discussed. Finally, the application prospects of nanowire-based high transparent solar cells were outlined. [ABSTRACT FROM AUTHOR]

With the rapid development of graphene technology, today graphene performs well in the application of light-emitting diode (LED) transparent electrodes. Naturally, high-quality contact between the graphene and the GaN underneath is very important. This paper reports a process for nickel-assisted transfer-free technology of graphene chemical vapor deposition on GaN. The nickel film plays the dual role of etching mask and growth catalyst, and is removed by the subsequent "penetration etching" process, achieving good direct contact between the graphene and GaN. The results show that the graphene effectively improves the current spreading of GaN-based LEDs and enhances their electrical performance. This scheme avoids the wrinkles and cracks of graphene from the transfer process, and is not only suitable for the combination of graphene and GaN-based LEDs, but also provides a solution for the integration of graphene and other materials. [ABSTRACT FROM AUTHOR]

Achieving high-efficiency optoelectronic devices often requires the development of high transparency in the extended range and high-conductivity materials, which can be ensured by the high mobility of charge carriers being used as the electrode. Among the candidate materials, transparent conductive indium zinc oxide (IZO) has attracted significant interest because of its superior electron mobility (5−60 cm2/V·s) and the thermal stability of its structure. In this study, the IZO films were deposited by the radio frequency magnetron sputtering of the IZO ceramic target (containing 10 wt.% ZnO) by varying the two variables of the substrate temperature and the oxygen content in the working gas. Here, the importance of the deposition of the IZO films at a low substrate temperature, not exceeding 100 °C, in order to get the minimum values of the film resistivity is revealed. At a substrate temperature of 100 °C, the film deposited in pure argon demonstrated a minimum resistance of 3.4 × 10−4 Ω·cm. Despite the fact that, with the addition of O2 in the working gas, an increase in resistivity was observed, the IZO film that deposited under 0.4% O2 content demonstrated the highest mobility (μ = 35 cm2/V·s at ρ = 6.0 × 10−4 Ω·cm) and enhanced transparency in the visible (VIS, 400−800 nm) and near-infrared (NIR, 800−1250 nm) ranges (TVIS ≥ 77% and TNIR ≥ 76%). At an oxygen content above 0.4%, a significant deterioration in electrical properties and a decrease in optical characteristics were observed. SEM and XRD studies of the microstructure of the IZO films allowed the clarification of the effect of both the substrate temperature and the oxygen content on the functional characteristics of the transparent conducting IZO films. [ABSTRACT FROM AUTHOR]

A heterostructure composed of a combination of semi-metallic graphene (Gr) and high-absorption LaVO3 is ideal for high-performance translucent photodetector (PD) applications. Here, we present multilayer Gr/LaVO3 vertical-heterostructure semitransparent PDs with various layer numbers (L n ). At L n = 2, the PD shows the best performance with a responsivity (R) of 0.094 A Wâˆ'1 and a specific detectivity (D *) of 7.385 × 107 cm Hz1/2 Wâˆ'1 at 532 nm. Additionally, the average visible transmittance of the PD is 63%, i.e. it is semitransparent. We increased photocurrent (PC) by approximately 13%, from 0.564 to 0.635 ÎĽ A cmâˆ'2 by using an Al reflector on the semitransparent PD. The PC of an unencapsulated PD maintains about 86% (from 0.571 to 0.493 ÎĽ A cmâˆ'2) of its initial PC value after 2000 h at 25 °C temperature/30% relative humidity, showing good stability. This behavior is superior to that of previously reported graphene-based PDs. These results show that these PDs have great potential for semitransparent optoelectronic applications. [ABSTRACT FROM AUTHOR]

We demonstrate highly flexible and efficient organic light-emitting devices (OLEDs) using an ultra-smooth NAN anode. A template-stripping process was employed to create an ultra-smooth NAN anode on a photopolymer substrate. The flexible OLEDs obtained by this method maintained good electroluminescent properties and mechanical stability after bending. The efficiency of the flexible OLEDs was improved by 30.6% compared with conventional OLEDs deposited on PET/ITO substrate due to the enhanced hole injection from the ultra-smooth anode. [ABSTRACT FROM AUTHOR]

As an organic cation, quaternary ammonium salt was introduced as a control agent to synthesize silver nanowires. The important influence of quaternary ammonium salt on the preparation of silver nanowires was seriously investigated by varying the length of carbon chain and its amount. Results showed that using quaternary ammonium salt as the control agent can successfully control the growth of silver nanowires, of which the diameters ranging from 35.06 to 46.60 nm. The diameters of the as‐prepared silver nanowires tended to be smaller with a longer carbon chain. This work provides a new aspect for controllable preparation of silver nanowires. Furthermore, the as‐prepared silver nanowires were used to prepare transparent electrodes. They exhibited good optical performance with 95.6% transmittance at a low sheet resistance of 18 Ω/square, demonstrating their great potential in the application for touch screens. [ABSTRACT FROM AUTHOR]

High-work function transparent electrodes (HWFTEs) are key for establishing Schottky and Ohmic contacts with n-type and p-type semiconductors, respectively. However, the development of printable materials that combine high transmittance, low sheet resistance, and tunable work function remains an outstanding challenge. This work reports a high-performance HWFTE composed of Ag nanowires enveloped conformally by Ti 3 C 2 T x nanosheets (TA), forming a shell-core network structure. The printed TA HWFTEs display an ultrahigh transmittance (>94%) from the deep-ultraviolet (DUV) to the entire visible spectral region, a low sheet resistance (<15 Ω sq -1 ), and a tunable work function ranging from 4.7 to 6.0 eV. The introduction of additional oxygen terminations on the Ti 3 C 2 T x surface generates positive dipoles, which not only increases the work function of the TA HWFTEs but also elevates the TA/Ga 2 O 3 Schottky barrier, resulting in a high self-powered responsivity of 18 mA W -1 in Ga 2 O 3 diode DUV photodetectors, as demonstrated via experimental characterizations and theoretical calculations. Furthermore, the TA HWFTEs-based organic light-emitting transistors exhibit exceptional emission brightness of 5020 cd m -2 , being four-fold greater than that in Au electrodes-based devices. The innovative nano-structure design, work function tuning, and the revealed mechanisms of electrode-semiconductor contact physics constitute a substantial advancement in high-performance optoelectronic technology., (© 2024 The Author(s). Advanced Materials published by Wiley‐VCH GmbH.)

Abstract Intrinsically conducting polymers (ICPs), such as polyacetylene, polyaniline, polypyrrole, polythiophene, and poly(3,4‐ethylenedioxythiophene) (PEDOT), can have important application in flexible electronics owing to their unique merits including high conductivity, high mechanical flexibility, low cost, and good biocompatibility. The requirements for their application in flexible electronics include high conductivity and appropriate mechanical properties. The conductivity of some ICPs can be enhanced through a postpolymerization treatment, the so‐called “secondary doping.” A conducting polymer film with high conductivity can be used as flexible electrode and even as flexible transparent electrode of optoelectronic devices. The application of ICPs as stretchable electrode requires high mechanical stretchability. The mechanical stretchability of ICPs can be improved through blending with a soft polymer or plasticization. Because of their good biocompatibility, ICPs can be modified as dry electrode for biopotential monitoring and neural interface. In addition, ICPs can be used as the active material of strain sensors for healthcare monitoring, and they can be adopted to monitor food processing, such as the fermentation, steaming, storage, and refreshing of starch‐based food because of the resistance variation caused by the food volume change. All these applications of ICPs are covered in this review article.

Achieving high transmission of light through a highly conductive structure implemented on a semiconductor remains a challenge in optoelectronics as the transmission is inevitably deteriorated by absorption and Fresnel reflection. There have been numerous efforts to design structures with near-unity transmission, yet they are typically constrained by a trade-off between conductivity and optical transmission. To address this problem, we propose and demonstrate a transmission mechanism enabled by a monolithic GaSb subwavelength grating integrated with Au stripes (metalMHCG). Near-unity transmission of polarized light is achieved by inducing low-quality factor resonance in the air gaps between the semiconductor grating stripes, which eliminates light absorption and reflection by the metal. Our numerical simulation shows 97% transmission of transverse magnetic polarized light and sheet resistance of 2.2 ΩSq−1. The metalMHCG structure was realized via multiple nanopatterning and dry etching, with the largest transmission yet reported of ∼90% at a wavelength of 4.5 µm and above 75% transmission in the wavelength range from 4 to 10 µm and sheet resistance at the level of 26 ΩSq−1. High optical transmission is readily achievable using any high refractive index materials employed in optoelectronics. The design of the metalMHCG is applicable in a wide electromagnetic spectrum from near ultraviolet to infrared.

With the development of artificial intelligence and the Internet of Things, the number of sensory nodes is growing rapidly, leading to the exchange of large quantities of redundant data between sensors and computing units. In-sensor computing schemes, which integrate sensing and processing, have provided a promising route to addressing the sensing/processing bottleneck by reducing power consumption, time delay and hardware redundancy. In this study, an in-sensor computing architecture involving a photoelectronic cell based on a wafer-scale two-dimensional MoS2 thin film was demonstrated. The MoS2 photodetector cell used a top-gate device structure with indium tin oxide (ITO) as the transparent gate electrode, which exhibited high air-stability and a high photoresponsivity (R) up to 555.8 A W–1 at an illumination power density (Pin) of 16.0 µW cm–2 (λ = 500 nm). Additionally, a MoS2 photodetector array with uniform photoresponsive characteristics was achieved. Furthermore, logic gates, including inverter, NAND, and NOR, were achieved based on MoS2 photodetector cells. Such multifunctional and robust in-sensor computing was ascribed to the uniform wafer-scale MoS2 film grown by atomic layer deposition (ALD) and the unique device structure. Because the detection of optical signals and logic operations were achieved through MoS2 photodetector cells with area efficiency, the proposed in-sensor computing device paves the way for potential applications in high-performance, integrated sensing and processing systems.

NiTe2 thin films have been considered promising candidates for transparent electrodes due to their high electrical conductivity and 2-dimensional (2D) layered structure. The transparency of 2D thin films with layered structure can be further improved by the exfoliation process. In the process, the increase in electrical resistance should be minimized by maintaining electrical continuity in the thin film. In this study, the mixing ratio of ethanol, acetone, and DI water in the solvent for the liquid-phase exfoliation (LPE) process was optimized to achieve high transmittance while suppressing the increase in electrical resistance. We prepared three solvents by varying the mixing ratio (ethanol:acetone:DI water = 2:4:4, 3:3:4, and 4:2:4). In the three mixed solvents, NiTe2 thin films were removed by two mechanisms: separation from the substrate and layer-by-layer exfoliation. Some of the NiTe2 grains were separated from the glass substrate in the early stage of the LPE process, and layer-by-layer exfoliation became the major mechanism when LPE proceeded longer than 6 h in the three solvents. Among the three solvents, the one with a 3:3:4 ratio more effectively suppressed the increase in electrical resistance during the separation of the NiTe2 thin film. The separation of NiTe2 grains provided an advantageous condition for layer-by-layer exfoliation. Additionally, the similarity of the polarization and dispersion ratio of 3-3-4 with the one of NiTe2 accelerated layer-by-layer exfoliation. The optimized solvent of 3-3-4 improved the transmittance of the NiTe2 thin film from 59.6% to 68.4% after the 8-h LPE process. [ABSTRACT FROM AUTHOR]