Wearable and Semitransparent Pressure-Sensitive Light-Emitting Sensor Based on Electrochemiluminescence.

Tactile sensors are being researched as a key technology for developing an electronic skin and a wearable display, which have recently been attracting much attention. However, to develop a next-generation wearable tactile sensor, it is necessary to implement an interactive display that responds immediately to external stimuli. Herein, a wearable and semitransparent pressure-sensitive light-emitting sensor (PLS) based on electrochemiluminescence (ECL) is successfully implemented with visual alarm functions to prevent damage to the human body from external stimuli.

Violet Light-Emitting Diodes Based on p-CuI Thin Film/n-MgZnO Quantum Dot Heterojunction.

As the lighting technology evolves, the need for violet light-emitting diodes (LEDs) is growing for high color rendering index lighting. The present technology for violet LEDs is based on the high-cost GaN materials and metal-organic chemical vapor deposition process; therefore, there have recently been intensive studies on developing low-cost alternative materials and processes. In this study, for the first time, we demonstrated violet LEDs based on low-cost materials and processes using a p-CuI thin film/n-MgZnO quantum dot (QD) heterojunction.

High-Performance Flexible ZnO Nanorod UV/Gas Dual Sensors Using Ag Nanoparticle Templates.

Flexible zinc oxide (ZnO) nanorod (NR) ultraviolet (UV)/gas dual sensors using silver (Ag) nanoparticle (NP) templates were successfully fabricated on a polyimide substrate with nickel electrodes. Arrays of Ag NPs were used as a template for the growth of ZnO NRs, which could enhance the flexibility and the sensing properties of the devices through the localized surface plasmon resonance (LSPR) effect. The Ag NPs were fabricated by the rapid thermal annealing process of Ag thin films, and ZnO NRs were grown on Ag NPs to maximize the surface area and form networks with rod-to-rod contacts.

High-performance flexible ZnO nanorod UV photodetectors with a network-structured Cu nanowire electrode.

In this work, vertically aligned zinc oxide (ZnO) nanorod (NR)-based flexible ultraviolet (UV) photodetectors were successfully fabricated on a polyimide (PI) substrate with a copper (Cu) nanowire (NW) electrode. To enhance the flexibility and sensing properties, the entangled networks of Cu NWs were applied to UV photodetectors as a flexible electrode. Here, Cu NWs have a high conductivity with a low cost compared to other metals to achieve a Schottky contact with ZnO NRs.

Adopting Novel Strategies in Achieving High-Performance Single-Layer Network Structured ZnO Nanorods Thin Film Transistors.

High-performance, solution-processed transparent and flexible zinc oxide (ZnO) nanorods (NRs)-based single layer network structured thin film transistors (TFTs) were developed on polyethylene terephthalate (PET) substrate at 100 °C. Keeping the process-temperature under 100 °C, we have improved the device performance by introducing three low temperature-based techniques; regrowing ZnO to fill the void spaces in a single layer network of ZnO NRs, passivating the back channel with polymer, and adopting ZrO2 as the high-k dielectric. Notably, high-k amorphous ZrO2 was synthesized and deposited using a novel method at an unprecedented temperature of 100 °C.

Bi-functional ion exchangers for enhanced performance of dye-sensitized solar cells.

Ion exchange using aerosol OT (AOT) offers dye adsorption twice as fast as known methods. Moreover, it suppresses the dye-agglomeration that may cause insufficient dye-coverage on the photoelectrode surface. Consequently, its dual function of fast dye-loading and higher dye-coverage significantly improves the power conversion efficiency of dye-sensitized solar cells.

Temperature-stable high-energy-density capacitors using complex perovskite thin films.

Chemical-solution-derived thin film synthesis and dielectric characterizations of (1 - x)BaTiO(3-x)Bi(Mg,Ti) O(3) complex perovskites with compositions x <0.15 have been explored for temperature-stable high-energy-density capacitor applications. Solution chemistry has been optimized to synthesize and stabilize the precursor solution.