A fully transparent quantum dot light-emitting diode (QD-LED) was fabricated by incorporating two types (anode and cathode) of graphene-based electrodes, which were controlled in their work functions and sheet resistances. Either gold nanoparticles or silver nanowires were inserted between layers of graphene to control the work function, whereas the sheet resistance was determined by the number of graphene layers. The inserted gold nanoparticles or silver nanowires in graphene films caused a charge transfer and changed the work function to 4.9 and 4.3 eV, respectively, from the original work function (4.5 eV) of pristine graphene. Moreover the sheet resistance values for the anode and cathode electrodes were improved from ∼63,000 to ∼110 Ω/sq and from ∼100,000 to ∼741 Ω/sq as the number of graphene layers increased from 1 to 12 and from 1 to 8, respectively. The main peak wavelength, luminance, current efficiency, and optical transmittance of the fully transparent QD-LED integrated with graphene anode and cathode were 535 nm, ∼358 cd/m2, ∼0.45 cd/A, and 70-80%, respectively. The findings of the study are expected to lay a foundation for the production of high-efficiency, fully transparent, and flexible displays using graphene-based electrodes.

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We report on a flexible ultraviolet (UV) photodetector fabricated using an all-spray-coating process. Two spray coating units were utilized to deposit semiconducting tin oxide nanowires as an active channel layer and metallic silver nanowires as an electrode layer. The device was mounted on the back of a human hand, and the UV intensities in sunlight were monitored over time. The fabricated flexible UV photodetector showed highly sensitive, stable, and reproducible detection properties. The main advantage of the proposed fabrication method is the extension of the integration environment by allowing direct application on various substrates, such as clothes and human skin, with varying device size and shape.

We report on a ternary device consisting of two nanowire channels that have different threshold voltage (Vth) values and show that three current stages can be produced. A microscale laser-beam shot was utilized to selectively anneal the nanowire channel area to be processed, and the amount of Vth shift could be controlled by adjusting the laser wavelength. Microscale laser annealing process could control Vth of the individual nanowire transistors while maintaining the other parameters the constant, such as the subthreshold slope, on–off current ratio, and mobility. This result could provide a potential for highly integrated and high-speed ternary circuits.

We report the fabrication of a highly transparent nanowire transistor using graphene as the gate and source-drain electrodes. Graphene gatesource-drain electrodes were simultaneously formed by a single-step transfer process. The graphene electrode and the nanowire channel exhibited near-ohmic contact characteristics. The threshold voltage, subthreshold slope, and mobility of the fabricated top-gate-structural In 2 O 3 nanowire transistor with graphene gate-source-drain electrodes were À4:54 V, 0.43 V/dec, and 78 cm 2 /(VÁs) respectively. The optical transmissions in the region that contained nanowire transistors on the quartz substrate were 88.5-90.3% in the 400-780 nm wavelength range.