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Memristors for neuromorphic computing have gained prominence over the years for implementing synapses and neurons due to their nano-scale footprint and reduced complexity. Several demonstrations show two-dimensional (2D) materials as a promising platform for the realization of transparent, flexible, ultra-thin memristive synapses. However, unsupervised learning in a spiking neural network (SNN) facilitated by linearity and symmetry in synaptic weight update has not been explored thoroughly using the 2D materials platform. Here, we demonstrate that graphene/MoS2/SiOx/Ni synapses exhibit ideal linearity and symmetry when subjected to identical input pulses, which is essential for their role in online training of neural networks. The linearity in weight update holds for a range of pulse width, amplitude and number of applied pulses. Our work illustrates that the mechanism of switching in MoS2-based synapses is through conductive filaments governed by Poole-Frenkel emission. We demonstrate that the graphene/MoS2/SiOx/Ni synapses, when integrated with a MoS2-based leaky integrate-and-fire neuron, can control the spiking of the neuron efficiently. This work establishes 2D MoS2 as a viable platform for all-memristive SNNs.

Various near-atom-thickness two-dimensional (2D) van der Waals (vdW) crystals with unparalleled electromechanical properties have been explored for transformative devices. Currently, the availability of 2D vdW crystals is rather limited in nature as they are only obtained from certain mother crystals with intrinsically possessed layered crystallinity and anisotropic molecular bonding. Recent efforts to transform conventionally non-vdW three-dimensional (3D) crystals into ultrathin 2D-like structures have seen rapid developments to explore device building blocks of unique form factors. Herein, we explore a "peel-and-stick" approach, where a nonlayered 3D platinum sulfide (PtS) crystal, traditionally known as a cooperate mineral material, is transformed into a freestanding 2D-like membrane for electromechanical applications. The ultrathin (∼10 nm) 3D PtS films grown on large-area (cm

The desire to enhance the efficiency of organic light-emitting devices (OLEDs) has driven to the investigation of advanced materials with fascinating properties. In this work, the efficiency of top-emission OLEDs (TEOLEDs) is enhanced by introducing ampicillin microstructures (Amp-MSs) with dual phases (α-/β-phase) that induce photoluminescence (PL) and electroluminescence (EL). Moreover, Amp-MSs can adjust the charge balance by Fermi level (E

Neuromorphic visual systems emulating biological retina functionalities have enormous potential for in-sensor computing, with prospects of making artificial intelligence ubiquitous. Conventionally, visual information is captured by an image sensor, stored by memory units, and eventually processed by the machine learning algorithm. Here, we present an optoelectronic synapse device with multifunctional integration of all the processes required for real time object identification. Ultraviolet-visible wavelength-sensitive MoS

Platinum ditelluride (PtTe2) is an emerging semimetallic two-dimensional (2D) transition-metal dichalcogenide (TMDC) crystal with intriguing band structures and unusual topological properties. Despite much devoted efforts, scalable and controllable synthesis of large-area 2D PtTe2 with well-defined layer orientation has not been established, leaving its projected structure-property relationship largely unclarified. Herein, we report a scalable low-temperature growth of 2D PtTe2 layers on an area greater than a few square centimeters by reacting Pt thin films of controlled thickness with vaporized tellurium at 400 °C. We systematically investigated their thickness-dependent 2D layer orientation as well as its correlated electrical conductivity and surface property. We unveil that 2D PtTe2 layers undergo three distinct growth mode transitions, i.e., horizontally aligned holey layers, continuous layer-by-layer lateral growth, and horizontal-to-vertical layer transition. This growth transition is a consequence of competing thermodynamic and kinetic factors dictated by accumulating internal strain, analogous to the transition of Frank-van der Merwe (FM) to Stranski-Krastanov (SK) growth in epitaxial thin-film models. The exclusive role of the strain on dictating 2D layer orientation has been quantitatively verified by the transmission electron microscopy (TEM) strain mapping analysis. These centimeter-scale 2D PtTe2 layers exhibit layer orientation tunable metallic transports yielding the highest value of ∼1.7 × 106 S/m at a certain critical thickness, supported by a combined verification of density functional theory (DFT) and electrical measurements. Moreover, they show intrinsically high hydrophobicity manifested by the water contact angle (WCA) value up to ∼117°, which is the highest among all reported 2D TMDCs of comparable dimensions and geometries. Accordingly, this study confirms the high material quality of these emerging large-area 2D PtTe2 layers, projecting vast opportunities employing their tunable layer morphology and semimetallic properties from investigations of novel quantum phenomena to applications in electrocatalysis.

Layered transition metal dichalcogenide (TMD) crystals in reduced dimensions have exhibited a wide range of extraordinary physical and chemical properties spanning from exotic quantum phenomena to unusually superior chemical reactivity. Their anisotropic van der Waals (vdW) bonding nature enables them to commonly possess two-dimensional (2D) structures which have been rigorously investigated recently. Nonetheless, TMD crystals in quasi zero-dimensional (0D) forms, i.e., TMD fullerenes, have not been explored in depth from the perspective of reproducible synthesis and process–structure correlation. Herein, we report a controlled synthesis of inorganic fullerene platinum diselenide (PtSe2) via a thermal selenization of Pt nanostructured precursors. We identified a conversion of Pt nanocubes to PtSe2 “onion-like” fullerenes, dictated by a well-defined isotropic volume expansion. Extensive transmission electron microscopy (TEM) inspections revealed that there exists a certain size-dependency which leads to the preferable growth of PtSe2 fullerenes over 2D PtSe2 platelets. The underlying principle for this size-dependent growth is discussed in the context of surface energy minimization. Furthermore, the PtSe2 fullerenes were verified to possess a large degree of unsaturated dangling bonds as well as internal strain, verified by Raman spectroscopy and X-ray photoelectron spectroscopy (XPS) as well as a geometric phase analysis (GPA). This study sheds light on synthesizing a wide range of TMD-based fullerenes which will foster the discovery of novel physical and chemical properties in quasi 0D material systems.

Various poly(lactic-co-glycolic acid) (PLGA) microspheres loaded with the ginger fraction were fabricated by controlling the electrospray parameters and their biocompatibility and antibacterial activity were identified in this study. The morphology of the microspheres was observed using scanning electron microscopy. The core-shell structures of the microparticles and the presence of ginger fraction in the microspheres were confirmed by fluorescence analysis using a confocal laser scanning microscopy system. In addition, the biocompatibility and antibacterial activity of PLGA microspheres loaded with ginger fraction were evaluated through a cytotoxicity test using osteoblast MC3T3-E1 cells and an antibacterial test using Streptococcus mutans and Streptococcus sanguinis, respectively. The optimum PLGA microspheres loaded with ginger fraction were fabricated under electrospray operational conditions with 3% PLGA concentration in solution, an applied voltage of 15.5 kV, a flow rate of 15 µL/min in the shell nozzle, and 3 µL/min in the core nozzle. The effectual antibacterial effect and enhanced biocompatibility were identified when a 3% ginger fraction in PLGA microspheres was loaded.

Recombination of photogenerated electron-hole pairs dominates the photocarrier lifetime and then influences the performance of photodetectors and solar cells. In this work, we report the design and fabrication of band-aligned van der Waals-contacted photodetectors with atomically sharp and flat metal-semiconductor interfaces through transferred metal integration. A unity factor α is achieved, which is essentially independent of the wavelength of the light, from ultraviolet to near-infrared, indicating effective suppression of charge recombination by the device. The short-circuit current (0.16 μA) and open-circuit voltage (0.72 V) of the band-aligned van der Waals-contacted devices are at least 1 order of magnitude greater than those of band-aligned deposited devices and 2 orders of magnitude greater than those of non-band-aligned deposited devices. High responsivity, detectivity, and polarization sensitivity ratio of 283 mA/W, 6.89 × 10

This study investigated the biocompatibility of strontium-doped calcium phosphate (Sr-CaP) coatings on pure magnesium (Mg) surfaces for bone applications. Sr-CaP coated specimens were obtained by chemical immersion method on biodegradable magnesium. In this study, Sr-CaP coated magnesium was obtained by immersing pure magnesium in a solution containing Sr-CaP at 80 °C for 3 h. The corrosion resistance and biocompatibility of magnesium according to the content of Sr-CaP coated on the magnesium surface were evaluated. As a result, the corrosion resistance of Sr-CaP coated magnesium was improved compared to pure magnesium. In addition, it was confirmed that the biocompatibility of the group containing Sr was increased. Thus, the Ca-SrP coating with a reduced degradation and improved biocompatibility could be used in Mg-based orthopedic implant applications.

We report a novel strategy to assemble wafer-scale two-dimensional (2D) transition metal dichalcogenide (TMD) layers of well-defined components and orientations. We directly grew a variety of 2D TMD layers on "water-dissoluble" single-crystalline salt wafers and precisely delaminated them inside water in a chemically benign manner. This manufacturing strategy enables the automated integration of vertically aligned 2D TMD layers as well as 2D/2D heterolayers of arbitrary stacking orders on exotic substrates insensitive to their kind and shape. Furthermore, the original salt wafers can be recycled for additional growths, confirming high process sustainability and scalability. The generality and versatility of this approach have been demonstrated by developing proof-of-concept "all 2D" devices for diverse yet unconventional applications. This study is believed to shed a light on leveraging opportunities of 2D TMD layers toward achieving large-area mechanically reconfigurable devices of various form factors at the industrially demanded scale.

Controlling the shape and crystallography of nanocrystals during the early growth stages of a noble metal layer is important because of its correlation with the final layer morphology and optoelectrical features, but this task is unattainable in vapor deposition processes dominated by artificially uncontrollable thermodynamic free energies. We report on experimental evidence for the controllable evolution of Ag nanocrystals as induced by the addition of nitrogen, presumed to be nonresidual in the Ag lattice given its strong float-out behavior. This atypical formation of energetically stable Ag nanocrystals with significantly improved wetting abilities on a chemically heterogeneous substrate promotes the development of an atomically flat, ultrathin, high-purity Ag layer with a thickness of only 5 nm. This facilitates the fabrication of Ag thin-film electrodes exhibiting highly enhanced optical transparency over a broad spectral range in the visible and near-infrared spectral range. An Ag thin-film electrode with a ZnO/Ag/ZnO configuration exhibits an average transmittance of about 95% in the spectral range of 400-800 nm with a maximum transmittance of over 98% at 580 nm, which is comparable with the best transparency values so far reported for transparent electrodes. This degree of optical transparency provides an excellent chance to improve the photon absorption of photovoltaic devices employing an Ag thin film as their window electrode. This is clearly confirmed by the superior performance of a flexible organic solar cell with a power conversion efficiency of 8.0%, which is far superior to that of the same solar cell using a conventional amorphous indium tin oxide electrode (6.4%).

Improving the wetting ability of Ag on chemically heterogeneous oxides is technically important to fabricate ultrathin, continuous films that would facilitate the minimization of optical and electrical losses to develop qualified transparent Ag film electrodes in the state-of-the-art optoelectronic devices. This goal has yet to be attained, however, because conventional techniques to improve wetting of Ag based on heterogeneous metallic wetting layers are restricted by serious optical losses from wetting layers. Herein, we report on a simple and effective technique based on the partial oxidation of Ag nanoclusters in the early stages of Ag growth. This promotes the rapid evolution of the subsequently deposited pure Ag into a completely continuous layer on the ZnO substrate, as verified by experimental and numerical evidence. The improvement in the Ag wetting ability allows the development of a highly transparent, ultrathin (6 nm) Ag continuous film, exhibiting an average optical transmittance of 94% in the spectral range 400-800 nm and a sheet resistance of 12.5 Ω sq-1, which would be well-suited for application to an efficient front window electrode for flexible solar cell devices fabricated on polymer substrates.

The intrinsically anisotropic crystallinity of two-dimensional (2D) transition metal dichalcogenide (2D TMD) layers enables a variety of intriguing material properties which strongly depend on the physical orientation of constituent 2D layers. For instance, 2D TMDs with vertically-aligned layers exhibit numerous dangling bonds on their 2D layer edge sites predominantly exposed on the surface, projecting significantly improved physical and/or chemical adsorption capability compared to their horizontally-oriented 2D layer counterparts. Such property advantages can be further promoted as far as the material can be integrated onto unconventional substrates of tailored geometry/functionality, offering vast opportunities for a wide range of applications which demand enhanced surface area/reactivity and mechanical flexibility. Herein, we report a new form of 2D TMDs, i.e., three-dimensionally ordered 2D molybdenum disulfide (2D MoS2) with vertically-aligned layers integrated on elastomeric substrates and explore their tunable multi-functionalities and technological promise. We grew large-scale (>2 cm2) vertically-aligned 2D MoS2 layers using a three-dimensionally patterned silicon dioxide (SiO2) template and directly transferred/integrated them onto flexible polydimethylsiloxane (PDMS) substrates by taking advantage of the distinguishable water-wettability of 2D MoS2vs. SiO2. The excellent structural integrity of the integrated vertical 2D MoS2 layers was confirmed by extensive spectroscopy/microscopy characterization. In addition, the stretch-driven unique tunability of their optical and surface properties was also examined. Moreover, we applied this material for flexible humidity sensing and identified significantly improved (>10 times) sensitivity over conventionally-designed horizontal 2D MoS2 layers, further confirming their high potential for unconventional flexible technologies.

The development of highly efficient flexible transparent electrodes (FTEs) supported on polymer substrates is of great importance to the realization of portable and bendable photovoltaic devices. Highly conductive, low-cost Cu has attracted attention as a promising alternative for replacing expensive indium tin oxide (ITO) and Ag. However, highly efficient, Cu-based FTEs are currently unavailable because of the absence of an efficient means of attaining an atomically thin, completely continuous Cu film that simultaneously exhibits enhanced optical transmittance and electrical conductivity. Here, strong two-dimensional (2D) epitaxy of Cu on ZnO is reported by applying an atomically thin (around 1 nm) oxygen-doped Cu wetting layer. Analyses of transmission electron microscopy images and X-ray diffraction patterns, combined with first-principles density functional theory calculations, reveal that the reduction in the surface and interface free energies of the wetting layers with a trace amount (1-2 atom %) of oxygen are largely responsible for the two-dimensional epitaxial growth of the Cu on ZnO. The ultrathin 2D Cu layer, embedded between ZnO films, exhibits a highly desirable optical transmittance of over 85% in a wavelength range of 400-800 nm and a sheet resistance of 11 Ω sq

This study compares the mechanical properties and wear ability of five CAD/CAM (computer-aided design/computer-aided manufacturing) millable dental blocks. All the discs, including Amber Mill Hybrid, Vita Enamic, Katana Avencia, Lava Ultimate, and Amber Mill, were cut in dimensions of 1.2 mm in thickness and 12 mm in diameter, polished to a machined surface, and immersed in distilled water for seven days. Vickers hardness was measured and the indentations were observed using microscope. The discs were brushed under a 150 g load. Mean surface roughness (Ra) and topography were determined after 100,000 cycles. Finally the biaxial flexure strength of the discs was measured and the broken surfaces were observed using scanning electron microscopy (SEM). The data was subjected to Weibull analysis. All data were analyzed by one-way analysis (ANOVA). The results of Vickers hardness are shown as: Amber Mill &gt, Vita Enamic &gt, Amber Mill Hybrid &gt, Lava Ultimate &gt, Katana Avencia. Katana Avencia showed the highest volume percentage reduction and the roughest surface after toothbrushing. The biaxial flexural strength is shown as: Amber Mill &gt, Katana Avencia &gt, Vita Enamic. All the tested materials exhibited varying degrees of mass loss and surface roughness. The properties of the composite materials are related to the filler content, filler volume, and polymerization methods.

Multi walled carbon nanotubes-hydroxyapatite (MWCNTs-HA) with various contents of MWCNTs was synthesized using the sol-gel method. MWCNTs-HA composites were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). HA particles were generated on the surface of MWCNT. Produced MWCNTs-HA nanocomposites were coated on pure titanium (PT). Characteristic of the titanium coated MWCNTs-HA was evaluated by field-emission scanning electron microscopy (FE-SEM) and XRD. The results show that the titanium surface was covered with MWCNTs-HA nanoparticles and MWCNTs help form the crystalized hydroxyapatite. Furthermore, the MWCNTs-HA coated titanium was investigated for in vitro cellular responses. Cell proliferation and differentiation were improved on the surface of MWCNT-HA coated titanium.

A binder-free and solvent-free pencil-trace electrode with intercalated clay particles (mainly SiO2) is prepared via a simple pencil-drawing process on grinded Cu substrate with rough surface and evaluated as an anode material for lithium-ion battery. The pencil-trace electrode exhibits a high reversible capacity of 672 mA h g(-1) at 100 mA g(-1) after 100 cycles, which can be attributed to the unique multilayered graphene particles with lateral size of few micrometers and the formation of LixSi alloys generated by interaction between Li(+) and an active Si produced in the electrochemical reduction of nano-SiO2 in the clay particles between the multilayered graphene particles. The multilayered graphene obtained by this process consists of 1 up to 20 and occasionally up to 50 sheets and thus can not only help accommodating the volume change and alleviating the structural strain during Li ion insertion and extraction but also allow rapid access of Li ions during charge-discharge cycling. Drawing with a pencil on grinded Cu substrate is not only very simple but also cost-effective and highly scalable, easily establishing graphitic circuitry through a solvent-free and binder-free approach.

We fabricated ZnS/diamond-like carbon (DLC) core-shell heterostructure nanowire using a simple two-step process: the vapor-liquid-solid method combined with radio frequency plasma enhanced chemical vapor deposition (rf PECVD). As a core nanowire, ZnS nanowires with face-centered cubic structure were synthesized with a sputtered Au thin film, which exhibit a length and a diameter of ~10 μm and ~30–120 nm . After rf PECVD for DLC coating, The length and width of the dense ZnS/DLC core-shell nanowires were a range of ~10 μm and 50–150 nm , respectively. In addition, ZnS/DLC core-shell nanowires were characterized with scanning transmission electron microscopy. From the results, the products have flat and uniform DLC coating layer on ZnS nanowire in spite of high residual stress induced by the high sp3fraction. To further understanding of the DLC coating layer, Raman spectroscopy was employed with ZnS/DLC core-shell nanowires, which reveals two Raman bands at 1550 cm−1(G peak) and 1330 cm−1(D peak). Finally, we investigated the optical properties from ultraviolet to infrared wavelength region using ultraviolet-visible (UV-Vis) and Fourier transform infrared (FT-IR) spectrometry. Related to optical properties, ZnS/DLC core-shell nanowires exhibit relatively lower absorbance and higher IR transmittance than that of ZnS nanowires.

We demonstrate the charge transport characteristics of MoS2-based vertical heterojunction devices through the formation of interfacial strain. Atomically thin MoS2 bilayers were directly synthesized on a p-type Si substrate by using chemical vapor deposition to introduce an interfacial tensile strain in the vertical heterojunction diode structure, which was confirmed by Raman, X-ray and ultraviolet photoelectron spectroscopy techniques. The electrical and optoelectronic properties of the heterojunction devices with the as-grown MoS2 (A-MoS2) on p-Si were compared with those of transferred MoS2 (T-MoS2)/p-Si devices. To clearly understand the charge transport characteristics induced by the interfacial tensile strain, the Fowler–Nordheim (FN) analysis of the electrical properties of the diode devices was conducted with the corresponding energy band diagrams. All of the fabricated MoS2-based vertical diodes exhibited clearly rectifying behaviors, but the photoresponse properties of the A-MoS2-based and T-MoS2-based heterojunctions exhibited distinct differences. Interestingly, we found that the tunneling barrier heights of the A-MoS2-based heterojunction devices were relatively higher than those of the T-MoS2-based devices and were almost the same before and after illumination due to the interfacial tensile strain, whereas those of the T-MoS2-based devices were lowered after illumination. Our study will help further understand the charge transport properties of 2D material-based heterojunction devices in the presence of interfacial strain, ultimately enabling the design of electronic and optoelectronic devices with novel functionalities.

With increasing interests in emergent wearable technologies such as e-skin healthcare devices, it is essential to develop new materials that can satisfy their demanded attributes; e.g., mechanical strain-invariant electrical and thermal properties. In this regard, two-dimensional (2D) transition metal dichalcogenide (TMD) layered materials have received tremendous attention owing to their intrinsic suitability, such as large tolerance limits under mechanical deformation coupled with decent electrical and thermal properties. However, these intrinsic advantages are often compromised upon their large wafer-scale integrations onto deformable substrates, which is commonly observed with conventional liquid-based or mechanical exfoliation approaches. In this paper, we demonstrate high-performance electrically-stretchable heaters by combining 2D platinum ditelluride (PtTe2) layers – a relatively unexplored class of 2D TMDs – with a strain engineering design scheme. We directly grew wafer-scale 2D PtTe2 layers on soft polyimide (PI) substrates by taking advantage of their low growth temperature. We verified their intrinsically low sheet resistance as low as 19.4 Ω/□ (thus, high electrical conductivity), which is superior to most other 2D TMDs. We then explored their Joule heating efficiencies and demonstrated they greatly surpass the performances of previously explored flexible heaters employing state-of-the-art nanomaterials including graphene, silver nanowires (Ag NWs), carbon nanotubes (CNTs) and their hybrids. By employing Kirigami patterning approaches for judicious strain engineering, we developed high-efficiency skin attachable 2D PtTe2 layers-based Kirigami heaters, which exhibited nearly strain-invariant excellent electrical-thermal properties; e.g., voltage-driven reliable heat generation upon a cyclic application/termination of 70% tensile stretch for 1000 times. We believe this study on intrinsically metallic 2D layered material will open up new venues for futuristic high-performance large-scale stretchable electronic applications of wearable thermotherapy, e-textile, and soft actuators.

Atomically thin transition metal dichalcogenides (TMDs) have recently attracted great attention since the unique and fascinating physical properties have been found in various TMDs, implying potential applications in next-generation devices. The progress towards developing new functional and high-performance devices based on TMDs, however, is limited by the difficulty of producing large-area monolayer TMDs due to a lack of knowledge of the growth processes of monolayer TMDs. In this work, we have investigated the growth processes of monolayer WS2 crystals using a thermal chemical vapor deposition method, in which the growth conditions were adjusted in a systematic manner. It was found that, after forming WO3-WS2 core-shell nanoparticles as nucleation sites on a substrate, the growth of three-dimensional WS2 islands proceeds by ripening and crystallization processes. Lateral growth of monolayer WS2 crystals subsequently occurs by surface diffusion process of adatoms. Our results provide understanding of the growth processes of monolayer WS2 by using chemical vapor deposition methods.

TiO2 nanotubes (TNT) formation is beneficial for improving bone cell–material interaction and drug delivery for Ti dental implants. Among the natural drugs to be installed in TNT, selected propolis has antibacterial and anti-inflammatory properties. It is a resinous natural product which is collected by the honeybees from the various types of plants with their salivary enzymes. This study concludes that TNT loaded with a propolis (PL-TNT-Ti) dental implant has the ability to improve osseointegration. The propolis particles were embedded within the TNT or adhered to the top. In a cytotoxicity test using osteoblast, PL-TNT-Ti group exhibited an increased cell proliferation and differentiation. A Sprague Dawley rat mandibular model was used to evaluate the osseointegration and bone bonding of TNT or PL-TNT-Ti. From the µ-CT and hematoxylin and eosin (HE) histological results after implantation at 1 and 4 weeks to rat mandibular, an increase in the extent of new bone formation and mineral density around the PL-TNT-Ti implant was confirmed. The Masson’s trichrome staining showed the expression of well-formed collagenous for bone formation on the PL-TNT-Ti. Immunohistochemistry staining indicate that bone morphogenetic proteins (BMP-2 and BMP-7) around the PL-TNT-Ti increased the expression of collagen fibers and of osteogenic differentiation whereas the expression of inflammatory cytokine such as interleukin-1 beta (IL-1s) and tumor necrosis factor-alpha (TNF-α) is decreased.

We here report the use of thin layers of graphene oxide (GO) as a protective coating that inhibits corrosion of underlying magnesium (Mg) metal. In order to coat the GO layer, Mg surfaces were hydroxylated with NaOH solution followed by silanization with dipping in 3-aminopropyltriethoxysilane (APTES) solution and subsequent coating with GO. Here, electrochemical methods were employed to study the corrosion behavior of Mg by coating graphene on it using multi-step coatings. Potentiodynamic polarization measurement determined that the graphene coating effectively inhibited the metal from corrosion. Electrochemical impedance spectroscopy (EIS) measurements suggested that graphene film on metal surface protect the metal from oxidation. This was as a result of impermeability of GO coatings to ions diffuse of oxidizing gas and corrosive liquid solution.

The effect of varying degrees of surface and vertical coverage of gold nanoparticles (Au-NPs) by poly(styrenesulfonate)-doped poly(3,4-ethylenedioxythiophene) (PSS), which was used as a capping layer between indium tin oxide (ITO) and a hole transport layer (HTL) on small-molecule fluorescent organic light-emitting diodes (OLEDs), was systemically investigated. With respect to the Au-NP loading amount and size, the resultant current densities influenced the charge balance and, therefore, the OLED device performance. When the capping layer consisted of ITO/Au-NPs/PSS+Au-NPs, superior device performance was obtained with 10-nm Au-NPs through increased surface coverage in comparison to other Au-NP PEDOT:PSS coverage conditions. Furthermore, the Au-NP size determined the vertical coverage of the capping layer. The current densities of OLEDs containing small Au-NPs (less than 30 nm, small vertical coverage) covered byPSS decreased because of the suppression of the hole carriers by the Au-NP trapping sites. However, the current densities of the devices with large Au-NPs (over 30 nm, large vertical coverage) increased. The increased electromagnetic fields observed around relatively large Au-NPs under electrical bias were attributed to increased current densities in the OLEDs, as confirmed by the finite-difference time-domain simulation. These results show that the coverage conditions of the Au-NPs by thePSS clearly influenced the OLED current density and efficiency.

This study was performed to evaluate the effect of a lithium-disilicate spray-liner application on both the bond strength between zirconia cores and heat-pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of all-ceramic zirconia crowns. A lithium-disilicate reinforced liner was applied on the surface of a zirconia core and lithium-disilicate glass-ceramic was veneered on zirconia through heat press forming. Microtensile and crown fracture tests were conducted in order to evaluate, respectively, the bonding strength between the zirconia cores and heat pressed lithium-disilicate glass-ceramic veneers, and the fracture strength of bilayered zirconia all-ceramic crowns. The role of lithium-disilicate spray-liner at the interface between zirconia and lithium-disilicate glass-ceramic veneers was investigated through surface and cross-sectional analyses. We confirmed that both the mean bonding strength between the zirconia ceramics and lithium-disilicate glass-ceramic veneers and the fracture strength of the liner-treated groups were significantly higher than those of the untreated groups, which resulted, on the one hand, from the chemical bonding at the interface of the zirconia and lithium-disilicate liner, and, on the other, from the existence of a microgap in the group not treated with liner.

This study was conducted to test the hypothesis that heat-bonding with a liner positively affects the bond strength and fracture resistance of an implant-supported glass&ndash, ceramic crown bonded to a zirconia abutment produced by a computer-aided design/computer-aided milling (CAD/CAM) procedure. Lithium disilicate-reinforced Amber Mill-Q glass ceramic blocks were bonded to 3 mol% yttria stabilized tetragonal zirconia polycrystal (3Y-TZP) blocks by heat-bonding with a liner or cementation with a dual-cure self-adhesive resin cement for a microtensile bond strength test. CAD/CAM implant-supported glass ceramic crowns were produced using Amber Mill-Q blocks and bonded to a milled 3Y-TZP zirconia abutments by heat-bonding or cementation for a fracture test. A statistical analysis was conducted to investigate the significant differences between the experimental results. The mode of failure was analyzed using high-resolution field emission scanning electron microscopy. Chemical bonding was identified at the interface between the zirconia ceramic and liner. The mean tensile bond strength of the liner-bonded group was significantly higher than that of the cement-bonded group. The initial chipping strength of the liner-bonded group was significantly higher than that of the cement-bonded group, although no statistically significant difference was found for the fracture strength. The mode of failure was mixed with cohesive fracture through the liner, whereas the cement-bonded group demonstrated adhesive failure at the interface of bonding.

Our study proposes a novel strategy for the synthesis of Ag derivatives (AgX@Ag (X = Cl and Br) or Ag nano/microtubes) using the controlled chemical reduction or electron-beam irradiation of AgX nanowires (NWs), which are formed from the controlled dewetting of a AgX thin film on colloidal particles. The size of the AgX@Ag and Ag nano/microtubes can be controlled using the AgCl NWs as templates and varying the concentration of NaX. By controlling the concentration of NaBr, heterojunction-structured AgCl/AgBr NWs (H-AgCl/AgBr NWs) can be produced from the AgCl NWs due to a partial ion-exchange reaction (low concentration), and the AgBr NWs produced after a complete ion-exchange reaction between Cl- and Br- are further grown into micrometer-sized AgBr wires (high concentration). The resulting AgX NWs can be transformed into corresponding AgX@Ag or Ag nano/microtubes via a controlled chemical or physical method. The AgX derivatives (AgX@Ag nanotubes (NTs) and AgX NWs) are tested as visible-light-induced photocatalysts for decomposition of methyl orange. The AgX@Ag NTs exhibit the best photocatalytic activities due to the advantages of the core@shell structure, allowing multiple reflections of visible light within the interior cavity, providing a well-defined and clean Ag/AgX interface, and preventing direct adsorption of pollutants on AgX because of the shell structure. These advantages allow AgX@Ag NTs to maintain high catalytic performance even after multiple uses. The approach can also be used as a direct method for preparing Ag nano/microtubes with a tailored size and as a new method for incorporating a AgX NW core into a Ag nano/microtube shell. Our approach is useful for synthesizing various types of one-dimensional heterostructured NWs or metal NTs with controlled structures and properties.

Rod-shaped ordered mesoporous carbons (OMCs) with different lengths, prepared by replication method using the corresponding size-tunable SBA-15 silicas with the same rodlike morphology as templates, are explored as anode material for Li-ion battery. All of the as-synthesized OMCs exhibit much higher Li storage capacity and better cyclability along with comparable rate capability as compared with commercial graphite. Particularly, the OMC-3 with the shortest length demonstrates the highest reversible discharge capacity of 1012 mAh g(-1) at 100 mA g(-1) and better cyclability with 86.6% retention of initial capacity after 100 cycles. Although the Coulombic efficiencies of all the OMCs are relatively low at the beginning, they improve promptly and after 10 cycles reach the level comparable to commercial graphite. Based on their specific capacity, cycle efficiency, and rate capability, the OMC-3 outperforms considerably its carbon peers, OMC-1 and OMC-2 with longer length. This behavior is mainly attributed to higher specific surface area, which provides more active sites for Li adsorption and storage along with the larger mesopore volume and shorter mesopore channels, which facilitate fast Li ion diffusion and electrolyte transport. The enhancement in reversible Li storage performance with decrease in the channel length is also supported by low solid electrolyte interphase resistance, contact resistance, and Warburg impedance in electrochemical impedance spectroscopy.

We report a morphotropic phase transformation in vanadium dioxide (VO2) nanobeams annealed in a high-pressure hydrogen gas, which leads to the stabilization of metallic phases. Structural analyses show that the annealed VO2 nanobeams are hexagonal-close-packed structures with roughened surfaces at room temperature, unlike as-grown VO2 nanobeams with the monoclinic structure and with clean surfaces. Quantitative chemical examination reveals that the hydrogen significantly reduces oxygen in the nanobeams with characteristic nonlinear reduction kinetics which depend on the annealing time. Surprisingly, the work function and the electrical resistance of the reduced nanobeams follow a similar trend to the compositional variation due mainly to the oxygen-deficiency-related defects formed at the roughened surfaces. The electronic transport characteristics indicate that the reduced nanobeams are metallic over a large range of temperatures (room temperature to 383 K). Our results demonstrate the interplay between oxygen deficiency and structural/electronic phase transitions, with implications for engineering electronic properties in vanadium oxide systems.

We investigate strain-induced optical modulation in a ZnO microwire with wavy geometries induced by mechanical strains. Curved sections of the wavy ZnO microwire show red-/blue-shifts of near-band-edge emission and broadening of full width at half maximum in cathodoluminescence spectra along the length of the wavy ZnO microwire, compared with straight sections. The observed variations indicate that local strains in the wavy ZnO microwire lead to strain-dependent local changes of its energy band structure. The local bending curvature calculations using a geometric model also provide correlation between the shift of the near-band-edge emission peaks and the bending strain.

This study examined the in vitro cell-material interactions on four different types of titanium surfaces: a polished Ti surface, TiO 2 nanotube surfaces fabricated in a fluorinated glycerol solution (TN), fluorinated glycerol solution with 1 wt% anionic surfactant sodium dodecyl sulphate (TN-SDS), and fluorinated glycerol solution with 1 wt% cationic surfactant cetyl trimethyl ammonium bromide (TN-CTAB), respectively. The surfaces exhibited distinct surface morphologies and geometrical features. Surface energy calculation shows that TN surface enhances the hydrophilic character by significantly increasing the surface energy. The osteoblast cell growth behavior on the four different surfaces was examined using the MC3T3-E1 cell line for 1 day. When the anodized surfaces were compared for the cell-materials interaction, each of the surfaces showed different properties that affected the cell–material interactions. Proliferation of the cells was noticed with distinctive cell-to-cell attachment on the TN surfaces. Good cellular adhesion with extracellular matrix extensions between the cells was noticed in the TN samples. The TiO 2 nanotubes grown in the surfactant-assisted fluorinated electrolyte did not show significant cell growth on the surface and some cell death was observed. The cell adhesion, differentiation and alkaline phosphatase activity were more pronounced on the TN surface. The MTT assays also revealed an increase in living cell density and proliferation on the TN surfaces. Overall, a rough surface morphology and surface energy are important factors for better cell material interactions.

ZrO2-embedded carbon fibers were prepared for use as an electromagnetic interference (EMI) shielding material by electrospinning and heat treatment methods. Structural changes were observed in the ZrO2 and in the carbon structures by XRD and Raman spectroscopy, respectively. During heat treatment, XRD analysis results revealed a transition from a monoclinic structure to a tetragonal structure in ZrO2 and a graphitization in the structural formation of carbon fibers was observed by Raman spectroscopy. It was observed that these structural changes in the ZrO2 and the carbon fibers improved the real and imaginary permittivities by a factor of more than 3.5. The EMI shielding efficiency (SE) improved along with the permittivity with higher treatment temperatures and greater amounts of embedded ZrO2; the highest average EMI SE achieved was 31.79 dB in 800–8500 MHz. The heat treatment played an important role in the improvements in the permittivity and in the EMI SE because of the heat-induced structural changes of the ZrO2-embedded electrospun carbon fibers. We suggest that the EMI shielding of the fibers is primarily due to the absorption of electromagnetic waves, which prevents secondary EMI by reflection of electromagnetic waves.

A combination of carbon nanotubes (CNTs) and titanium (Ti) modified with TiO2 nanotubes (TiO2 NTs) was fulfilled with the aim of improving bioactivity of Ti implant. First, well-ordered TiO2 NTs were prepared by the electrochemical anodization of Ti in an ethylene glycol electrolyte containing 1 wt% NH4F and 10 wt% H2O at 20 V for 50 min, followed by annealing. Then, the carboxylated CNTs were coated onto the TiO2 NTs using electrophoretic deposition (EPD) technique. The growth of hydroxyapatite (HA) on the samples was investigated by soaking them in simulated body fluid (SBF). The result showed the CNTs-coated Ti with the modification of TiO2 NTs (CNTs-TiO2 NTs) was more efficient to induce HA formation than the CNTs-coated smooth Ti (CNTs-Ti). The vitro cell response was evaluated using osteoblast cells (MC3T3-E1). The good cell proliferation and strong cell adhesion could be obtained on the CNTs-TiO2 NTs. These results indicated that CNT coating on the Ti modified with TiO2 NTs could be potentially useful for the periodontal ligament combination on dental implants.

In situ composite coating of hydroxyapatite (HA)/TiO 2 were produced on titanium (Ti) substrate by micro-arc oxidation coupled with electrophoretic deposition (MAO&EPD) technique with different concentrations of HA particles in the 0.2 M NaOH electrolyte solution. The surface morphology and chemical composition of the hybrid coating were effected by HA concentration. The amount of HA particles incorporated into coating layer increased with increasing HA concentration used in the electrolyte solution. The corrosion behavior of the coating layer in simulated body fluids (SBF) was evaluated using a potentiodynamic polarization test. The corrosion resistance of the coated sample was increased compared to the untreated Ti sample. The in vitro bioactivity assessment showed that the MAO&EPD treated Ti substrate possessed higher apatite-forming ability than the untreated Ti. Moreover, the apatite-forming ability had a positive correlation with HA concentration. In addition, the cell behavior was also examined using cell proliferation assay and alkaline phosphatase ability. The coating formed at HA concentration of 5 g/L exhibited the highest cell ability.

The dispersing power of different surfactant-modified multiwalled carbon nanotubes (MWCNTs) and their effect on the antibacterial activity were examined. Three surfactants, including hexadecyltrimethylammonium bromide (CTAB), triton X-100 (TX-100) and sodium dodecyl sulfate (SDS) were tested. UV–vis absorbance, transmission electron microscopy and Fourier transform infrared spectroscopy were used to characterize the dispersion of MWCNTs in the aqueous phase, showing that the surfactant molecules had been adsorbed onto the MWCNTs’ surface. Among the three surfactants, TX-100 and CTAB provided maximum and minimum dispersion, respectively. The surfactant-modified MWCNTs exhibited different antibacterial activities to Streptococcus mutans. The fluorescence images showed that the surfactant-modified MWCNTs were not only capable of capturing bacteria and forming cell aggregates, but also killing them. Under the same concentration and treatment time, the CTAB-modified MWCNTs exhibited the strongest antibacterial activity compared to the TX-100 and SDS-modified MWCNTs. The optical density growth curves and viable cell number determined by the plating method suggested that the antibacterial activity of all surfactant-modified MWCNTs was both concentration- and treatment time-dependent.

A high-performance NO gas sensor was prepared by inducing thermal fluorination of carbon nanotube semiconductors. Thermal fluorination of multi-walled carbon nanotubes (MWCNTs) was carried out at various temperatures (100 ∼ 1000 °C) to investigate the effects of the reaction temperature. The mechanism of high-performance NO gas sensor electrode was shown to depend on the fluorination temperature in a way that can be divided into three regions, separated at 400 and 1000 °C. In the first temperature region, the induction of fluorine functional groups onto MWCNTs showed the opposite trend in electrical resistance change comparing with traditional p-type MWCNTs. In the second temperature region, the induced fluorine functional groups were attenuated by generated fluorinated carbon gases resulting in the decomposition of MWCNTs and the recovery of traditional p-type gas sensor behavior. In the highest temperature region above 1000 °C, reoriented carbon structure was observed, showing bent nanotubes produced from destruction by fluorination and subsequent reorientation due to the high temperature. The gas sensing responsiveness was significantly improved by the thermal fluorination, which causes electrophilic attraction, creates adsorption sites for target NO gases and improve hydrophobicity for gas sensing stability in humid condition. In conclusion, a high-performance gas sensor was obtained by thermal-fluorination of MWCNTs.

An easy aqueous 'one-pot' synthesis route for the fabrication of single crystalline uniform iron hydroxide (beta-FeOOH) nanorods at low temperature is reported. beta-FeOOH nanorods with diameters of 5-37 nm and lengths up to 45-185 nm were obtained by varying the reaction parameters. Addition of ethanol was found to be crucial to control the aspect ratio. After calcination at 250 degrees C for 2 h the as-obtained beta-FeOOH nanorods was converted to alpha-Fe2O3 nanorods. To the best of our knowledge, beta-FeOOH nanorods having diameter less than 6 nm is reported for the first time.

Polyurethane fibers were fabricated using an electrospinning method with aluminum hydroxide and multi-walled carbon nanotubes (MWCNTs) as flame-retardant additives to improve the thermal oxidation stability of the polyurethane fibers. The MWCNTs were incorporated into the polyurethane fibers after oxyfluorination treatment to improve the dispersivity and compatability. The thermal properties and anti-oxidation stabilities of these polyurethane fibers were investigated under nitrogen and oxygen flows from room temperature to 600 °C to determine the effects of the MWCNTs and aluminum hydroxide additives. The aluminum hydroxide acted as an energy storage tank by releasing water, resulting in an endothermic reaction. The MWCNTs promoted the formation of a charred layer that acted as a protective film to prevent the decomposition of the polyurethane by oxygen radicals. The flame-retardant properties were also improved by an enhanced gel-type structural network generated by the MWCNTs. The integral procedure decomposition temperature and activation energy increased significantly, indicating that the flame-retardant properties of the polyurethane fibers improved. These results are attributed to the aluminum hydroxide, MWCNT additives, and the oxyfluorination treatment.

The pH-sensitive photocatalytic system was prepared by embedding TiO2 into poly(vinyl alcohol)/poly(acrylic acid) hydrogel. Two different type TiO2/hydrogel composites, such as matrix and nanofiber, were prepared to investigate the morphological effects on the photocatalytic activity. TiO2 was distributed uniformly in the composite hydrogel and kept the original anatase structure without any structural change. The photocatalytic activity of TiO2 was evaluated based on the efficiency of photobleaching of dye. The photobleaching of dye was improved greatly as the pH was changed into basic condition and the larger surface area of hydrogel was available for TiO2 by using nanofiber supports.

The effects of surface conditioning methods on the microtensile bond strength of Y-TZP ceramic were studied based on airborne particle abrasion and resin cements. Eight square-shaped (ϕ12 mm×5 mm high) Y-TZP ceramic were studied blocks (LAVA™, 3M ESPE, USA) and flat occlusal dentin blocks were fabricated, pre-treated(airborne abrasion with 125μm Al2O3 particles, tribochemical silica coating with 110 μm Al2O3 particles modified by silica oxide), and bonded to each other using resin cements(Panavia F 2.0, RelyX Unicem). Thereafter the trilayer specimens were cut into microbar specimens with a bonding area of approximately 1.0±0.1 mm2 and then microtensile bond strength tests were performed. The Y-TZP ceramic following airborne particle abrasion with 125μm Al2O3 and silicoating, the surface roughness of Y-TZP and its surface silica content were confirmed to increase. Overall, the Y-TZP ceramic surface treatment with a tribochemical silica coating showed the highest microtensile bond strength of the phosphate monomerbased resin cement to Y-TZP ceramic(mean MPa= 18.11±0.27(Panavia F 2.0), 17.45±0.39(RelyX Unicem). In cases in which a silica coating was applied, there was no significant difference in the bonding strength depending on resin cements (P>0.05).

We report the synthesis of a polyimide matrix with a low dielectric constant for application as an intercalation material between metal interconnections in electronic devices. Porous activated carbon was embedded in the polyimide to reduce the dielectric constant, and a thin film of the complex was obtained using the spin-coating and e-beam irradiation methods. The surface of the thin film was modified with fluorine functional groups to impart water resistance and reduce the dielectric constant further. The water resistance was significantly improved by the modification with hydrophobic fluorine groups. The dielectric constant was effectively decreased by porous activated carbon. The fluorine modification also resulted in a low dielectric constant on the polyimide surface by reducing the polar surface free energy. The dielectric constant of polyimide film decreased from 2.98 to 1.9 by effects of porous activated carbon additive and fluorine surface modification.

Gelatin-stabilized gold nanoparticles (AuNPs-gelatin) with controlled particle size were synthesized with simple variation of concentration of gelatin by reducing in situ tetrachloroauric acid with sodium citrate. The nanoparticles showed excellent colloidal stability. Transmission electron microscopy (TEM) revealed the formation of well-dispersed gold nanoparticles (AuNPs) with different sizes. The methodology produces particles 10–15 nm in size depending on the concentration of gelatin used. The measured AuNPs are 10, 11, 12, 13, 14, and 15 nm for AuNPs-gelatin 1, 0.5, 0.25, 0.1 and 0.05%, and pure AuNPs, respectively. The AuNPs-gelatin exhibit size-dependent localized surface plasmon resonance behavior as measured by UV–visible spectroscopy. UV–vis spectroscopy and TEM results suggest that higher concentration of gelatin favor smaller particle size and vice versa. FTIR spectroscopy analysis of AuNPs-gelatin revealed the amino bands and carboxyl peak of gelatin. The crystalline nature of AuNPs was investigated by X-ray diffraction.

Mg-35Zn-3Ca (wt.%) alloy containing nontoxic and biocompatible Zn and Ca as alloying elements was prepared and subjected to heat treatment and artificial aging for different duration of time to reduce its rate of degradation. Solution heat treatment was performed at 310°C while artificial aging was performed at 170°C for 0, 2.5, 5.0, 7.5, and 10.0 h and they were designated as AT0, AT1, AT2, AT3, and AT4, respectively. The finest and most homogenous reticulum was observed on the surface of the AT2 group. The result of immersion test in Hank’s balanced salt solution (HBSS) showed that the corrosion rate of the AT2 group was 2.32 mg/(cm2day), which was significantly lower as compared to other groupsP<0.05. The hemolysis value was ≤5% in all groups, indicating no toxicity during short-term blood reaction.

As the proportion of adult orthodontic treatment increases, mainly for aesthetic reasons, orthodontic brackets are directly attached to yttria-stabilized tetragonal zirconia polycrystal (Y-TZP) restorations. This, study analyzed the shear bond strength (SBS) between various surface treated Y-TZP and orthodontic metal brackets. The Y-TZP specimens were conditioned by 110 m Al2O3 sandblasting, or sandblasting followed by coating with one of the primers (silane, MDP, or an MDP-containing silane primer). After surface treatment, the orthodontic metal bracket was bonded to the specimen using a resin cement, and then 24 h storage in water and thermal cycling (5000 cycles, 5-55 degrees C), SBS was measured. Surface roughness was analyzed for surface morphology, and X-ray photoelectron spectroscopy (XPS) was employed for characterization of the chemical bond between the Y-TZP and the MDP-based primers (MDP, MDP containing silane primer). It was found that after surface treatment, the surface roughness of all groups increased. The groups treated with 110 m Al2O3 sandblasting and MDP, or MDP-containing silane primer showed the highest SBS values, at 11.92 +/- 1.51 MPa and 13.36 +/- 2.31 MPa, respectively. The SBS values significantly decreased in all the groups after thermal cycling. Results from XPS analysis demonstrated the presence of chemical bonds between Y-TZP and MDP. Thus, the application of MDP-based primers after Al2O3 sandblasting enhances the resin bond strength between Y-TZP and the orthodontic metal bracket. However, bonding durability of all the surface-treated groups decreased after thermal cycling.

A three-dimensional (3D) transparent conducting electrode, consisting of a quasi-periodic array of discrete indium-tin-oxide (ITO) nanoparticles superimposed on a highly conducting oxide–metal–oxide multilayer using ITO and silver oxide (AgOx) as oxide and metal layers, respectively, is synthesized on a polymer substrate and used as an anode in highly flexible organic solar cells (OSCs). The 3D electrode is fabricated using vacuum sputtering sequences to achieve self-assembly of distinct ITO nanoparticles on a continuous ITO–AgOx–ITO multilayer at room-temperature without applying conventional high-temperature vapour–liquid–solid growth, solution-based nanoparticle coating, or complicated nanopatterning techniques. Since the 3D electrode enhances the hole-extraction rate in OSCs owing to its high surface area and low effective series resistance for hole transport, OSCs based on this 3D electrode exhibit a power conversion efficiency that is 11–22% higher than that achievable in OSCs by means of conventional planar ITO film-type electrodes. A record high efficiency of 6.74% can be achieved in a bendable OSC fabricated on a poly(ethylene terephthalate) substrate.

The electrical resistance behavior of graphene was studied under oxidizing and reducing gas exposure. The graphene surface was modified via oxyfluorination to obtain a specific surface area and oxygen functional groups. Fluorine radicals provided improved pore structure and introduction of an oxygen functional group. A high-performance gas sensor was obtained based on enlarged target gas adsorption sites and an enhanced electron charge transfer between the target gas and carbon surface via improved pore structure and the introduction of oxygen functional groups, respectively.

In the present study, commercial purity Ti and Ti-6Al-4V alloy specimens with and without alkali- and heat-treatments were implanted in the abdominal connective tissue of mice. Conventional SUS 316L stainless steel was also implanted for comparison. After three months, their biocompatibility was evaluated by in vitro and in vivo experiments. When immersed in Hank's solution, which has ion concentrations similar to that of human blood, an apatite layer, which accelerates the connection with bone, formed easily on the alkali-treated specimens compared to the non-treated specimens. The number of macrophages, which is known to increase as the inflammation reaction proceeds, is much lower for the alkali-treated specimens than for other samples. The average thickness of the fibrous capsule formed around the implant is much thinner for the alkali-treated specimens than for the others. These results show that the alkali- and heat-treatments performed in the present study will be very effective for the improvement of biocompatibility.

We report that significantly more transparent yet comparably conductive AgOx films, when compared to Ag films, are synthesized by the inclusion of a remarkably small amount of oxygen (i.e., 2 or 3 atom %) in thin Ag films. An 8 nm thick AgOx (O/Ag=2.4 atom %) film embedded between 30 nm thick ITO films (ITO/AgOx/ITO) achieves a transmittance improvement of 30% when compared to a conventional ITO/Ag/ITO electrode with the same configuration by retaining the sheet resistance in the range of 10-20 Ω sq(-1). The high transmittance provides an excellent opportunity to improve the power-conversion efficiency of organic solar cells (OSCs) by successfully matching the transmittance spectral range of the electrode to the optimal absorption region of low band gap photoactive polymers, which is highly limited in OSCs utilizing conventional ITO/Ag/ITO electrodes. An improvement of the power-conversion efficiency from 4.72 to 5.88% is achieved from highly flexible organic solar cells (OSCs) fabricated on poly(ethylene terephthalate) polymer substrates by replacing the conventional ITO/Ag/ITO electrode with the ITO/AgOx/ITO electrode. This novel transparent electrode can facilitate a cost-effective, high-throughput, room-temperature fabrication solution for producing large-area flexible OSCs on heat-sensitive polymer substrates with excellent power-conversion efficiencies.