Transparent Conductors Research Articles

Mechanically Robust and Hydrophobic Poly(3,4-ethylenedioxythiophene)/Silica Hybrid Transparent Film Using Poly(styrenesulfonate-co-allyl methacrylate) as Template Material

We report a simple approach to enhance the mechanical stability and the hydrophobic property of the poly(3,4-ethylenedioxythiophene) (PEDOT) transparent conductive films (TCFs) by an in situ sol–gel hybrid approach. Poly(styrenesulfonate-co-allyl methacrylate) [P(SS-co-AMA)] was used as a template material to synthesize PEDOT:P(SS-co-AMA) aqueous dispersion. PEDOT:P(SS-co-AMA)/silica hybrid films were then prepared by thiol–ene click and sol–gel reactions using silane precursors like 3-mercaptopropyltrimethoxysilane (MPTMS), tetraethyl orthosilicate (TEOS) and perfluorooctyltriethoxysilane (POTES). Pristine PEDOT:P(SS-co-AMA) films on glass showed the electrical conductivity (σ) of 0.07 S/cm, while secondary doping with 5% DMSO increased the conductivity to 77.13 S/cm (transmittance over 92%). As silica is introduced, the electrical conductivity of the PEDOT:P(SS-co-AMA)/silica hybrid films decreased and was in the range of 2.27–76.20 S/cm. Furthermore, the silica hybrid films showed transmittance, >92%; water contact angle, >100°; and pencil hardness, >6H indicating improved hydrophobic property and mechanical stability due to the cross-linked silica network, perfluoro octyl moiety and good compatibility between the organic/inorganic phases. The PEDOT-silica hybrid films with good transparency and electrical conductivity and superior hydrophobic and mechanical properties are suitable candidates for durable optoelectronic device applications.

Self-assembled Growth of SnO2 Nanoshells on Copper Nanowires for Stable and Transparent Conductors

Despite a century of research, the inability to design flexible transparent electrodes with low cost and high stability has been the greatest obstacle in realizing flexible electronics. Herein, we report the growth of self-assembled SnO2 nanoshells on thin copper nanowire (Cu NW) networks using a simple and effective solution method. In addition, the SnO2–Cu NW flexible films exhibit an extremely low sheet resistance of ∼13.6 Ω/sq, with ∼83.5% optical transparency. In harsh environments (such as strong oxidation, heat, and humidity conditions), the films demonstrate excellent resistance stability, which can compete with the resistance stability of noble silver nanowire films. Particularly, the films are robust and able to withstand a high temperature of 210 °C without any deterioration of performance. Employing the outstanding stability of SnO2–Cu NWs, we also demonstrate the macroscopic use of a transparent conductor in a flexible transparent heater.

Fabrication of High Transmittance and High Mobility Transparent Conductive Oxide Films: Hydrogen-doped Indium Oxide

Designing and fabricating high-performance transparent conductive oxides (TCOs) is an attractive area for optoelectronic devices that require both high transparency and electrical conductivity. In this study, we introduce a hydrogen doping of indium oxide (IHO) as a TCO material with enhanced transparency while maintaining high conductivity by optimizing the carrier mobility, carrier concentration, and thickness. The typical IHO with a thickness of 200 nm exhibits a relatively lower carrier concentration (~2.10*1020 cm−3), compared to the traditional TCO like indium tin oxide and results in a higher NIR transmission of over 55% at 2500 nm, while the high carrier mobility of 87 cm2 V−1 s−1 endows it a lower sheet resistance of 15 Ω/sq. Our research provides valuable insights into the TCO and can be a general strategy to enhance light utilization for energy-efficient optoelectronic devices. Our work provides valuable insights into how the properties of TCOs can be tuned by controlling their microstructure and doping. The results show that hydrogen doping is an effective strategy to achieve the desired optical and electrical characteristics for efficient utilization of light in optoelectronics.

Layered metals as polarized transparent conductors

The quest to improve transparent conductors balances two key goals: increasing electrical conductivity and increasing optical transparency. To improve both simultaneously is hindered by the physical limitation that good metals with high electrical conductivity have large carrier densities that push the plasma edge into the ultra-violet range. Technological solutions reflect this trade-off, achieving the desired transparencies only by reducing the conductor thickness or carrier density at the expense of a lower conductance. Here we demonstrate that highly anisotropic crystalline conductors offer an alternative solution, avoiding this compromise by separating the directions of conduction and transmission. We demonstrate that slabs of the layered oxides Sr2RuO4 and Tl2Ba2CuO6+δ are optically transparent even at macroscopic thicknesses >2 μm for c-axis polarized light. Underlying this observation is the fabrication of out-of-plane slabs by focused ion beam milling. This work provides a glimpse into future technologies, such as highly polarized and addressable optical screens.

Ultrathin chromium oxide buffer layer by reactive thermal deposition for high-performance semitransparent perovskite solar cells

Transparent conductive oxide (TCO) films are widely used for semitransparent perovskite solar cells (st-PSCs) and perovskite-based tandem solar cells due to their high optical transparency and good electrical conductivity. However, the high-power sputtering damage during the deposition of TCO film is a vital factor to prevent the perovskite-based solar cells from achieving high efficiency. In this work, we develop an ultrathin chromium oxide (CrOx) buffer layer between the hole transporting layer (HTL) and indium-doped tin oxide (ITO) by trace-oxygen reactive thermal deposition (to-RTD). The experimental results show that the CrOx buffer layer can hinder the sputtering damage of ITO deposition and ensure a high-performance device, which can be attributed to the improved conductivity of the HTL/CrOx/ITO structure together with the tailored energy level alignment. In addition, this buffer layer with a thickness of 4 nm displays a high optical transmittance (>95%) in the interested wavelengths, meaning a limited optical parasitic absorption loss. As a result, the st-PSC with CrOx buffer layer achieves champion power conversion efficiency (PCE) of 19.06%, which is one of the highest PCEs for the n-i-p st-PSCs. Moreover, a four-terminal perovskite/silicon tandem solar cell featuring a CrOx buffer layer realizes a relatively high PCE of 27.48%.

Stretchable and Robust Silver Nanowire Composites on Transparent Butyl Rubber

Silver nanowires (AgNWs) are leading materials for transparent conductive electrodes in optoelectronic devices. The solution processability of AgNWs combined with the optical transparency and electrical conductivity of solution-deposited AgNW networks makes them a promising alternative to conventional indium tin oxide. Furthermore, the ability of AgNW networks to withstand mechanical deformation means that AgNW networks may be the material of choice for next-generation flexible and stretchable optoelectronics. The drawback with the practical use of AgNWs, however, is that corrosion of AgNWs under ambient conditions damages the AgNW network and reduces the workable life span. Environmental degradation is especially problematic in stretchable electronics, which use elastomeric substrate materials that have a high gas permeability like poly(dimethylsiloxane) (PDMS). Covering individual AgNWs with a protective nanoscale coating to prevent corrosion complexifies their preparation and implementation in practical applications. This study presents an alternative approach in which the elastomeric substrate, transparent butyl rubber (TBR), acts as both a stretchable substrate and a protective gas barrier. TBR, an optically transparent formulation of poly(isobutylene-co-isoprene), is a synthetic rubber with an intrinsically low gas permeability. We demonstrate that AgNW networks embedded in a polyurethane adhesive and adhered to a TBR substrate provide high conductivity and optical transparency and are robust to tensile strain as well as extreme environments of humidified air, underwater storage, and corrosive acid vapors. We show that this system outperforms a comparison system that uses PDMS instead of TBR.

Two-Dimensional Layered Structures of Group-V Elements as Transparent Conductors: Insight from a First-Principles Study

Exotic optoelectronic and transport properties of two-dimensional (2D) materials have made them the focus of several application-oriented studies. This work is a feasibility study of such 2D structures based on group-V elements as passivating/transparent conducting interlayers in photovoltaic applications. We present a detailed first-principles study of the optoelectronic and carrier-transport properties of the two most stable and experimentally synthesized allotropes ($\ensuremath{\alpha}$ and $\ensuremath{\beta}$) of $\mathrm{As}$, $\mathrm{Sb}$, and $\mathrm{Bi}$. Monolayers of both allotropes exhibit a band gap for all three elements, which decreases and eventually disappears beyond a critical number of layers (thickness). Interestingly, this transition from semiconducting to metallic behavior is found to be very different for $\mathrm{As}$ as compared with $\mathrm{Sb}$ and $\mathrm{Bi}$. $\ensuremath{\alpha}$-Arsenene remains semiconducting until the pentalayered structure, while $\ensuremath{\beta}$-arsenene becomes metallic beyond the bilayered structure. All other allotropes of $\mathrm{Sb}$ and $\mathrm{Bi}$ are semiconducting only for a monolayer. The in-plane conductivity of the monolayered structures lies in the range from ${10}^{4}$ to ${10}^{5}\phantom{\rule{0.2em}{0ex}}\mathrm{S}\phantom{\rule{0.1em}{0ex}}{\mathrm{m}}^{\ensuremath{-}1}$, and increases with increasing layer thickness. On the other hand, the monolayers exhibit the lowest reflectivity ($5\mathrm{%}$ or less), which increases to more than 25%, 50%, and 40% in the visible region for pentalayers of $\ensuremath{\alpha}$- and $\ensuremath{\beta}$-arsenene, antimonene, and bismuthene, respectively. Trilayered $\ensuremath{\alpha}$-arsenene, with a figure of merit (${T}^{10}/{R}_{\mathrm{sh}}$) of approximately $0.15\phantom{\rule{0.2em}{0ex}}\mathrm{mS}$, is a promising candidate as a transparent conducting layer in solar-cell applications. Such combined evaluation of 2D materials based on their optoelectronic and transport properties is quite useful for future experimental investigations.

High optoelectronic quality of AZO films grown by RF-magnetron sputtering for organic electronics applications

Aluminum-doped zinc oxide thin films, known by the acronym AZO, were grown by radio-frequency magnetron sputtering method (rf-magnetron sputtering) onto glass substrate at room temperature and without posterior heat treatment. The impact on the structural, electrical, and optical properties of the AZO films was studied as a function of the following deposition parameters: working pressure, rf-power and thickness. Our films showed low electrical resistivity and high transmittance in the visible region comparable to commercial indium tin oxide (ITO) films. We obtained an optimized AZO film with an electrical resistivity of 4.90 × 10−4 Ωcm and presented optical transmittance strikingly high for such a good conductor, with about 98% at 580 nm and an average optical transmittance of about 92% in the visible region. We also built and characterized an organic light-emitting diode (OLED) using the optimized AZO film as a transparent electrode. The AZO-based OLED showed characteristics comparable to a reference ITO-based device, indicating that AZO films have optoelectronic properties good enough to be used in organic electronics. In addition, the results suggest that they are suitable to be employed as transparent conductors in flexible polymeric substrates since their synthesis was performed without intentional heating.

Fabrication and processing of bacterial cellulose/silver nanowire composites as transparent, conductive, and flexible films for optoelectronic applications

AbstractThis work reports on the engineering and fabrication of transparent, conductive, and flexible films made as a composite of bacterial cellulose microfibers (BMF), a polymer (either PVA or PEO), and silver nanowires (AgNWs) as viable and cost‐effective replacements to commercial indium‐tin oxide (ITO) and fluorine‐doped tin oxide (FTO) transparent conductors. The studies conducted indicate that the optical and mechanical properties of BMF‐polymer substrates are tuneable by varying the ratio of BMF to polymer. An optimized ratio of 70:30 of BMF to polymer was established for BMF‐PVA and BMF‐PEO composites. The optimized composite films were coated with varying amounts of AgNWs. As the AgNW loading increased, the deposition density of AgNW networks increased, while the sheet resistance and optical transmittance decreased. The optimum AgNW loading was determined at 0.20 mg for both composite films. The BMF‐PVA‐AgNW film displayed transmittance between 81% and 71% and an average resistivity of 9.462 ± 0.588 Ω/sq while the BMF‐PEO‐AgNW films showed transmittance between 73% and 65% and an average resistivity of 9.388 ± 0.1.375 Ω/sq. These properties compared well to that of commercial ITO and FTO glass substrates. The findings promote cellulose‐based composites as low‐cost, lightweight, and durable substrates for optoelectronic applications.

The Influence of Oxygen‐Related Defects on the Formation of In2O3‐Based Low‐Fluorescence Transparent Conducting Film

When the fluorescence of a material under transparent conductive films is measured, it is sometimes required that the transparent conductive films have low fluorescence intensity to prevent stray light. Herein, the oxygen partial pressure during sputtering is varied and the transmittance, resistivity, and fluorescence intensity are measured to clarify the cause of the fluorescence of indium tin oxide (ITO) and In2O3. The fluorescence intensity of both ITO and In2O3 decreases with an increase in the oxygen partial pressure in the case of as‐deposited films. The cause of fluorescence is considered to be oxygen vacancies. ITO can maintain low resistivity even with a small amount of oxygen vacancies since it contains SnO2, which generates carriers. High‐temperature annealing also introduces other defects, which increases the fluorescence intensity.

Enhanced conductivity of infrared transparent Bi2Se3 thin films as anti-interference coatings for infrared detectors

Infrared transparent conductive coatings are extensively utilized in both military and civilian infrared detectors due to their superior infrared transmission and electromagnetic shielding properties. It is a major scientific challenge to find a solution to the contradiction between high transmittance and low conductivity in the area of wide-band infrared transparent conductive film research. This study utilized new material systems and film preparation technologies to clarify the problem. A higher c-axis preferred orientation infrared transparent conducting Bi2Se3 thin film on a p-Si (111) substrate was developed using plasma-enhanced chemical vapor deposition (PECVD) technology. At room temperature, the film exhibited n-type conductivity, with high surface mobility of 2565 cm2/V·s and low surface resistivity of 2.6 × 10−5 Ω cm. In the mid-IR and far-IR regions, the produced Bi2Se3 thin film displayed transparency of 90% and 80%, respectively. To the best of our knowledge, this n-type conductive thin film created using chemical vapor deposition is the best IR-transparent thin film to date. Using this film, a Bi2Se3/p-Si heterojunction diode with a maximum voltage of 0.7 V was created. Young's modulus and hardness were determined to be 80 ± 5.5 GPa and 15 ± 2.2 GPa, respectively, for the film. It demonstrates the film's resistance to wear and deformation. The findings imply that Bi2Se3 film may be used as an anti-interference coating for infrared detectors and other optoelectronic devices throughout a wide wavelength range, from the mid-IR to the far-IR, due to its good optical transparency and electrical conductivity.

Two-dimensional silver film for all-inorganic transparent photovoltaics

A transparent conductor with aluminum-doped zinc oxide (AZO)/Ag/Cu structure was developed and applied for extracting power from transparent photovoltaics. The Cu layer serves as seed layer for the two-dimensional growth of an Ag film. The AZO layer is used to enhance the optoelectrical properties of Cu/Ag. The AZO/Ag/Cu film exhibits a high visible transmittance of 83.1% and a sheet resistance of 18 Ω/□. Importantly, the proposed Cu/Ag/AZO transparent conductor enables the development of transparent and flexible NiO/ZnO-based photovoltaics with a power conversion efficiency of 1.14%. These results shows that the present system may be a promising platform for cost-effective and high-performance flexible optoelectronics.

Single Crystalline Transparent Conducting F, Al, and Ga Co-Doped ZnO Thin Films with High Photoelectrical Performance.

Transparent conductive film (TCF) is a material that integrates electrical conductivity and optical transparency. It is widely used as an electrode material in thin-film solar cells. However, considerable progress is needed to facilitate its high performance and low-cost preparation. In this study, a preparation scheme for AlF3 and GaF3 co-doped ZnO (FAGZO) thin films was designed and implemented by magnetron sputtering (MS). The mutual restraint between the electrical properties and the wide-spectrum transmission performance of ZnO films was resolved. First-principles calculations showed that the doped ZnO system had n-type conductivity and that the most stable structure was the FO-AlZn-GaZn system. The experimental results verified the theoretical predictions. Single crystalline ZnO transparent conducting films (ZnO-TCFs) of high quality were achieved by MS. After rapid thermal annealing (RTA) treatment, the mobility reached 49.6 cm2/V s, and the resistivity decreased to 3.82 × 10-4 Ω cm. The AT was 90% between 380 and 1200 nm. Furthermore, the application of the prepared FAGZO film in perovskite solar cells (PSCs) has been verified. Compared to the reference indium tin oxide film, the PSCs using the FAGZO film showed higher JSC and power conversion efficiency. These results demonstrate that MS combined with anion and cation co-doping provides an effective means of exploring high-quality and high-performance ZnO-TCFs.

Formation and Etching of the Insulating Sr‐Rich V5+ Phase at the Metallic SrVO3 Surface Revealed by Operando XAS Spectroscopy Characterizations

AbstractIn the search of low cost and more efficient electronic devices, here the properties of SrVO3 transparent conductor oxide (TCO) thin film are investigated, both visible‐range optically transparent and highly conductive, it stands as a promising candidate to substitute the standard indium‐tin‐oxide (ITO) in applications. Its surface stability under water (both liquid and vapor) and other gaseous atmospheres is especially addressed. Through the use of spectroscopy characterizations, X‐ray photoemission and operando X‐ray absorption measurements, the formation of a thin Sr‐rich V5+ layer located at the surface of the polycrystalline SrVO3 film with aging is observed, and for the first time how it can be removed from the surface by solvating in water atmosphere. The surface recovery is associated to an etching process, here spectroscopically characterized in operando conditions, allowing to follow the stoichiometric modification under reaction. Once exposed in oxygen atmosphere, the Sr‐rich V5+ layer forms again. The findings improve the understanding of aging effects in perovskite oxides, allowing for the development of functionalized films in which it is possible to control or to avoid an insulating surface layer. This constitutes an important step towards the large‐scale use of V‐based TCOs, with possible implementations in oxide‐based electronics.

Epitaxial Electrodeposition of Ordered Inorganic Materials.

ConspectusThe quality of technological materials generally improves as the crystallographic order is increased. This is particularly true in semiconductor materials, as evidenced by the huge impact that bulk single crystals of silicon have had on electronics. Another approach to producing highly ordered materials is the epitaxial growth of crystals on a single-crystal surface that determines their orientation. Epitaxy can be used to produce films and nanostructures of materials with a level of perfection that approaches that of single crystals. It may be used to produce materials that cannot be grown as large single crystals due to either economic or technical constraints. Epitaxial growth is typically limited to ultrahigh vacuum (UHV) techniques such as molecular beam epitaxy and other vapor deposition methods. In this Account, we will discuss the use of electrodeposition to produce epitaxial films of inorganic materials in aqueous solution under ambient conditions. In addition to lower capital costs than UHV deposition, electrodeposition offers additional levels of control due to solution additives that may adsorb on the surface, solution pH, and, especially, the applied overpotential. We show, for instance, that chiral morphologies of the achiral materials CuO and calcite can be produced by electrodepositing the materials in the presence of chiral agents such as tartaric acid.Inorganic compound materials are electrodeposited by an electrochemical-chemical mechanism in which solution precursors are electrochemically oxidized or reduced in the presence of molecules or ions that react with the redox product to form an insoluble species that deposits on the electrode surface. We present examples of reaction schemes for the electrodeposition of transparent hole conductors such as CuI and CuSCN, the magnetic material Fe3O4, oxygen evolution catalysts such as Co(OH)2, CoOOH, and Co3O4, and the n-type semiconducting oxide ZnO. These materials can all be electrodeposited as epitaxial films or nanostructures onto single-crystal surfaces. Examples of epitaxial growth are given for the growth of films of CuI(111) on Si(111) and nanowires of CuSCN(001) on Au(111). Both are large mismatch systems, and the epitaxy is explained by invoking coincidence site lattices in which x unit meshes of the film overlap with y unit meshes of the substrate.We also discuss the epitaxial lift-off of single-crystal-like foils of metals such as Au(111) and Cu(100) that can be used as flexible substrates for the epitaxial growth of semiconductors. The metals are grown on a Si wafer with a sacrificial SiOx interlayer that can be removed by chemical etching. The goal is to move beyond the planar structure of conventional Si-based chips to produce flexible electronic devices such as wearable solar cells, sensors, and flexible displays. A scheme is shown for the epitaxial lift-off of wafer-scale foils of the transparent hole conductor CuSCN.Finally, we offer some perspectives on possible future work in this area. One question we have not answered in our previous work is whether these epitaxial films and nanostructures can be grown with the level of perfection that is achieved in UHV. Another area that is ripe for exploration is the epitaxial electrodeposition of metal-organic framework materials from solution precursors.

Far-infrared transparent conductors

The long-standing challenge in designing far-infrared transparent conductors (FIRTC) is the combination of high plasma absorption edge (λp) and high conductivity (σ). These competing requirements are commonly met by tuning carrier concentration or/and effective carrier mass in a metal oxide/oxonate with low optical dielectric constant (εopt = 2–7). However, despite the high σ, the transparent band is limited to mid-infrared (λp < 5 μm). In this paper, we break the trade-off between high σ and λp by increasing the “so-called constant” εopt that has been neglected, and successfully develop the material family of FIRTC with εopt > 15 and λp > 15 μm. These FIRTC crystals are mainly octahedrally-coordinated heavy-metal chalcogenides and their solid solutions with shallow-level defects. Their high εopt relies on the formation of electron-deficiency multicenter bonds resulting in the great electron-polarization effect. The new FIRTC enables us to develop the first “continuous film” type far-infrared electromagnetic shielder that is unattainable using traditional materials. Therefore, this study may inaugurate a new era in far-infrared optoelectronics.

Long-range electrostatic contribution to electron-phonon couplings and mobilities of two-dimensional and bulk materials

Charge transport plays a crucial role in manifold potential applications of two-dimensional materials, including field-effect transistors, solar cells, and transparent conductors. At most operating temperatures, charge transport is hindered by scattering of carriers by lattice vibrations. Assessing the intrinsic phonon-limited carrier mobility is thus of paramount importance to identify promising candidates for next-generation devices. Here we provide a framework to efficiently compute the drift and Hall carrier mobility of two-dimensional materials through the Boltzmann transport equation by relying on a Fourier-Wannier interpolation. Building on a recent formulation of long-range contributions to dynamical matrices and phonon dispersions [Phys. Rev. X 11, 041027 (2021)], we extend the approach to electron-phonon coupling including the effect of dynamical dipoles and quadrupoles. We identify an unprecedented contribution associated with the Berry connection that is crucial to preserve the Wannier-gauge covariance of the theory. This contribution is not specific to two-dimensional crystals, but also concerns the three-dimensional case, as we demonstrate via an application to bulk SrO. We showcase our method on a wide selection of relevant monolayers ranging from ${\mathrm{SnS}}_{2}$ to ${\mathrm{MoS}}_{2}$, graphene, BN, InSe, and phosphorene. We also discover a nontrivial temperature evolution of the Hall hole mobility in InSe whereby the mobility increases with temperature above 150 K due to the Mexican-hat electronic structure of the InSe valence bands. Overall, we find that dynamical quadrupoles are essential and can impact the carrier mobility in excess of 75%.

Nb2CTx-Based MXenes Most Recent Developments: From Principles to New Applications

MXenes are progressively evolving two-dimensional (2D) materials with an expanding wide range of applications in the field of energy storage. They rank among the best electrode materials for cutting-edge energy storage systems. Energy storage device performance is greatly enhanced by MXenes and their composite materials. As technology has improved over the last several decades, the demand for high-capacity energy storage devices that are versatile, sturdy, and have cheap production costs has increased. MXene, which is based on Nb2CTx, is the most current material to emerge for energy storage applications. Nb2CTx MXene is now the most sought-after material in the 2D family due to its flexibility, high conductivity, superior electrochemical nature, superior hydrophilicity, tunable surface functional groups, great mechanical properties, and 2D layered structure. Examples include gas and biosensors, water splitting, water purification, antimicrobial coatings, electromagnetic interference shielding, and transparent electrical conductors. Because of the distinctive properties of Nb2CTx MXene, scientists are working on further theoretical and experimental enhancements. The objective of this work is to deliver an outline of current breakthroughs in Nb2CTx MXene for the construction of robust, flexible, and highly effective electrochemical energy storage devices powered by supercapacitors. Deep research has been conducted on the structure of Nb2CTx MXene, as well as on different synthesis techniques and their distinctive properties. The emphasis has also been placed on how various aspects, such as electrode architecture design, electrolyte composition, and so on, influence the charge storage device and electrochemical efficiency of Nb2CTx MXene-based supercapacitors. This article also discusses the most recent advancements in Nb2CTx MXene composite-based supercapacitors.

Flexible correlated 4d2 SrMoO3/mica thin films with enhanced optoelectronic performance and high bending stability

Recently, correlated metallic oxide (CMO) was proposed as a brand-new design strategy for transparent conductors (TCs). Among these CMOs, perovskite-type SrVO3 with an electronic configuration of 3 d1 has been most investigated. Herein, the SrMoO3 films, one 4 d2 perovskite CMO, were deposited on a flexible mica substrate using a pulsed laser deposition method. Our experimental results indicate that the SrMoO3 film possesses a superior optoelectronic performance compared with SrVO3, owing to the weaker electronic correlations and 4 d2 electronic configuration in SrMoO3. Bending cyclic tests indicate that the flexible SrMoO3/mica film has a high mechanical bending durability and stability. This 4 d2 SrMoO3/mica film demonstrates a great potential as a high-performance TC for flexible optoelectronics.

A method to computationally screen for tunable properties of crystalline alloys

Conventionally, high-throughput computational materials searches start from an input set of bulk compounds extracted from material databases, but, in contrast, many real functional materials are heavily engineered mixtures of compounds rather than single bulk compounds. We present a framework and open-source code to automatically construct and analyze possible alloys and solid solutions from a set of existing experimental or calculated ordered compounds, without requiring additional metadata except crystal structure. As a demonstration, we apply this framework to all compounds in the Materials Project to create a new, publicly available database of 600,000 unique "alloy pair" entries that can be used to search for materials with tunable properties. We exemplify this approach by searching for transparent conductors and reveal candidates that might have been excluded in a traditional screening. This work lays a foundation from which materials databases can go beyond stoichiometric compounds and approach a more realistic description of compositionally tunable materials.