Improving Charge-Imbalanced Problem of Quantum Dot Light-Emitting Diodes with TPBi/ZnO Electron Transport Layer.

To solve charge-imbalanced problem caused by excessive electron injection into the emitting layer (EML) of quantum dot light emitting diodes (QLEDs) with ZnO electron transport layer (ETL), we proposed QLEDs with TPBi((2,2',2''-(1,3,5-Benzinetriyl)-tris(1-phenyl-1-H-benzimidazole)))/ZnO ETL layered design. Spin coated TPBi demonstrated lower value of the lowest unoccupied molecular orbital (LUMO) than conduction band maximum (CBM) of ZnO, resulting in effective prevention of excessive injection of electrons into the EML even under excessive stress conditions. Experimental results demonstrated that QLEDs with TPBi/ZnO ETL not only could minimize charge imbalanced problem under high current density operation, but also could increase the maximum luminance of QLEDs by up to 156% (i.

Ultra-low Doping on Two-Dimensional Transition Metal Dichalcogenides using DNA Nanostructure Doped by a Combination of Lanthanide and Metal Ions.

Here, we propose a novel DNA-based doping method on MoS2 and WSe2 films, which enables ultra-low n- and p-doping control and allows for proper adjustments in device performance. This is achieved by selecting and/or combining different types of divalent metal and trivalent lanthanide (Ln) ions on DNA nanostructures, using the newly proposed concept of Co-DNA (DNA functionalized by both divalent metal and trivalent Ln ions). The available n-doping range on the MoS2 by Ln-DNA is between 6 × 10(9) and 2.

n- and p-Type doping phenomenon by artificial DNA and M-DNA on two-dimensional transition metal dichalcogenides.

Deoxyribonucleic acid (DNA) and two-dimensional (2D) transition metal dichalcogenide (TMD) nanotechnology holds great potential for the development of extremely small devices with increasingly complex functionality. However, most current research related to DNA is limited to crystal growth and synthesis. In addition, since controllable doping methods like ion implantation can cause fatal crystal damage to 2D TMD materials, it is very hard to achieve a low-level doping concentration (nondegenerate regime) on TMD in the present state of technology.

Poly-4-vinylphenol and poly(melamine-co-formaldehyde)-based graphene passivation method for flexible, wearable and transparent electronics.

Next generation graphene-based electronics essentially need a dielectric layer with several requirements such as high flexibility, high transparency, and low process temperature. Here, we propose and investigate a flexible and transparent poly-4-vinylphenol and poly(melamine-co-formaldehyde) (PVP/PMF) insulating layer to achieve intrinsic graphene and an excellent gate dielectric layer at sub 200 °C. Chemical and electrical effects of PVP/PMF layer on graphene as well as its dielectric property are systematically investigated through various measurements by adjusting the ratio of PVP to PMF and annealing temperature.

Selective formation of a latticed nanostructure with the precise alignment of DNA-templated gold nanowires.

A very efficient method is introduced to selectively align and uniformly separate λ-DNA molecules and thus DNA-templated gold nanowires (AuNW's) using a combination of molecular combing and surface-patterning techniques. By the method presented in this work, it is possible to obtain parallel and latticed nanostructures consisting of DNA molecules and thus DNA-templated AuNW's aligned at 400 nm intervals. DNA-templated AuNW's are uniformly formed with an average height of 2.

Electrical characteristics and doping mechanism of DNA molecules doped with iodine solutions.

This study examined the electrical characteristics of deoxyribonucleic acid (DNA) molecules doped with iodine solution and their chemical state changes before and after doping. The experiments were progressed in each lambda (A), poly(dA)-poly(dT) and poly(dG)-poly(dC) DNA under the same conditions. The authors prepared 20 nm gap Au/Ti electrodes fabricated by e-beam lithography.

Fabrication of highly uniform conductive polypyrrole nanowires with DNA template.

Deoxyribonucleic acid (DNA) is considered as one of the alternative materials for electronic device applications; however, DNA has critical limitation to electronic device applications due to its low electrical conductivity and unreliability. Therefore, it is required for electronic devices to prepare the well defined conductive polymer nanowires with DNA as a template. Polypyrrole (PPy) is an attractive polymer due to its high conductivity and environmental stability in bulk; although it is well known that ammonium persulfate (APS) used for the polymerization of pyrrole causes the deformation of DNA molecules.

Formation of lambda-DNA's in parallel- and crossed-line arrays by molecular combing and scanning-probe lithography.

With the combination of a molecular combing technique and scanning-probe lithographic patterning, lambda-DNA's were stretched and aligned to form line array structures on patterned organic monolayer surfaces. The pattern was generated by anodizing a silicon surface using scanning-probe lithography to implant a polar organic layer in the middle of a nonpolar layer. The molecule in the polar layer, (aminopropyl)triethoxysilane (APS), has a -NH(3)(+) terminal group, which interacts strongly with phosphate backbone of DNA and provides a site for selective attachment of DNA.