Thin-film field-effect transistor is a fundamental component behind various mordern electronics. The development of stretchable electronics poses fundamental challenges in developing new electronic materials for stretchable thin-film transistors that are mechanically compliant and solution processable. Here we report the fabrication of transparent thin-film transistors that behave like an elastomer film. The entire fabrication is carried out by solution-based techniques, and the resulting devices exhibit a mobility of ∼30 cm2 V−1 s−1, on/off ratio of 103–104, switching current >100 μA, transconductance >50 μS and relative low operating voltages. The devices can be stretched by up to 50% strain and subjected to 500 cycles of repeated stretching to 20% strain without significant loss in electrical property. The thin-film transistors are also used to drive organic light-emitting diodes. The approach and results represent an important progress toward the development of stretchable active-matrix displays.

The performance of a fl exible transparent conductive electrode with extremely smooth topography capable of withstanding thermal processing at 300 °C for at least 6 h with little change in sheet resistance and optical clarity is reported. In depth investigation is performed on atomic layer deposition (ALD) deposited ZnO on Ag nanowires (NWs) with regard to thermal and atmospheric corrosion stability. The ZnO coated nanowire networks are embedded within the surface of a polyimide matrix, and the <2 nm roughness freestanding electrode is used to fabricate a white polymer light emitting diode (PLED). PLEDs obtained using the ZnO-AgNW-polyimide substrate exhibit comparable performance to indium tin oxide (ITO)/glass based devices, verifying its efficacy for use in optoelectronic devices requiring high processing temperatures.

Highly flexible and efficient CH3NH3PbBr3 quantum dot based light-emitting diodes were developed on a silver nanowire–polymer composite electrode.

The extended lifetime of organic light‐emitting diodes (OLEDs) based on enhanced electrical stability of a silver nanowire (AgNW) transparent conductive electrode is reported. Specifically, in depth investigation is performed on the ability of atomic layer deposition deposited zinc oxide (ZnO) on AgNWs to render the nanowires electrically stable during electrical stressing at the range of operational current density used for OLED lighting. ZnO‐coated AgNWs have been observed to show no electrical, optical, or morphological degradation, while pristine AgNW electrodes have become unusable for optoelectronic devices due to dramatic decreases in conductivity, transparency, and fragmentation of the nanowire network at ≈150 mA cm−2. When fabricated into OLED substrates, resulting OLEDs fabricated on the ZnO‐AgNW platform exhibit a 140% increase in lifetime when compared to OLEDs fabricated on indium tin oxide (ITO)/glass, and ≈20% when compared to OLEDs fabricated on AgNW based substrates. While both ZnO‐coated and pristine AgNW substrates outperform ITO/glass due to the lower current densities required to drive the device, morphological stability in response to current stressing is responsible for the enhancement of lifetime of ZnO‐AgNW based OLEDs compared to pristine AgNW based OLEDs.

Zirconium oxide nanoparticles are promising candidates for optical engineering, photocatalysis, and high-κ dielectrics. However, reported synthetic methods for the colloidal zirconium oxide nanoparticles use unstable alkoxide precursors and have various other drawbacks, limiting their wide application. Here, we report a facile one-pot method for the synthesis of colloidally stable zirconium oxide nanoparticles. Using a simple solution of zirconium trifluoroacetate in oleylamine, highly stable zirconium oxide nanoparticles have been synthesized with high yield, following a proposed amidization-assisted sol-gel mechanism. The nanoparticles can be readily dispersed in nonpolar solvents, forming a long-term stable transparent solution, which can be further used to fabricate high-refractive-index nanocomposites in both monolith and thin-film forms. In addition, the same method has also been extended to the synthesis of titanium oxide nanoparticles, demonstrating its general applicability to all group IVB metal oxide nanoparticles.

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A flexible, nanocomposite substrate for maximizing light outcoupling efficiencies of organic light emitting diodes (OLEDs) is introduced. In depth investigation is performed on designing the integrated strategy based on considerations of surface conductivity, microcavity tuning, and internal light scattering. The resulting nanocomposite substrate consists of silver nanowires as the electrode and a high index polymer layer and a light scattering layer for light extraction. It is able to outcouple both the waveguide and the substrate modes, two modes accounting for significant losses in OLED device efficiency. With enhanced light outcoupling, white OLEDs subsequently fabricated on the nanocomposite substrates demonstrate performance metrics of 107 lm W -1 power efficiency and 49% external quantum efficiency at 1,000 cd/m 2 . The nanocomposite substrate is fabricated by solution processes at low temperatures for potentially low manufacturing cost.

We report vertical electrolyte-gated red, green, and blue phosphorescent small-molecule organic light-emitting diodes (OLED), in which light emission was modified by tuning the electron injection via electrochemical doping of the electron injection layer 4,4-bis(N-carbazolyl)-1,1-biphenyl (CBP) under the assistance of a polymer electrolyte. These devices comprise an electrolyte capacitor on the top of a conventional OLED, with the interfacial contact between the electrolyte and electron injection layer CBP of OLEDs achieved through a porous cathode. These phosphorescent OLEDs exhibit the tunable luminance between 0.1 and 10 000 cd m, controlled by an applied bias at the gate electrode. This simple device architecture with gate-modulated luminance provides an innovative way for full-color OLED displays.