Hydrogen Sensing Performance of ZnO Schottky Diodes in Humid Ambient Conditions with PMMA Membrane Layer.

Enhanced hydrogen sensing performance of Pt Schottky diodes on ZnO single crystal wafers in humid ambient conditions is reported using a polymethylmethacrylate (PMMA) membrane layer. ZnO diode sensors showed little change in forward current when switching to wet ambient H conditions with 100% relative humidity. This sensitivity drop in the presence of water vapor can be attributed to surface coverage of hydroxyl groups on the Pt surface in humid ambient conditions.

Clear Wood toward High-Performance Building Materials.

Developing advanced building materials with both excellent thermal insulating and optical properties to replace common glass (thermal conductivity of ∼1 W m K) is highly desirable for energy-efficient applications. The recent development of transparent wood suggests a promising building material with many advantages, including high optical transmittance, tunable optical haze, and excellent thermal insulation. However, previous transparent wood materials generally have a high haze (typically greater than 40%), which is a major obstacle for their practical application in the replacement of glass.

Influence of High-Energy Proton Irradiation on β-GaO Nanobelt Field-Effect Transistors.

The robust radiation resistance of wide-band gap materials is advantageous for space applications, where the high-energy particle irradiation deteriorates the performance of electronic devices. We report on the effects of proton irradiation of β-GaO nanobelts, whose energy band gap is ∼4.85 eV at room temperature.

Novel microbial photobioelectrochemical cell using an invasive ultramicroelectrode array and a microfluidic chamber.

Objective: To fabricate a novel microbial photobioelectrochemical cell using silicon microfabrication techniques.

Results: High-density photosynthetic cells were immobilized in a microfluidic chamber, and ultra-microelectrodes in a microtip array were inserted into the cytosolic space of the cells to directly harvest photosynthetic electrons. In this way, the microbial photobioelectrochemical cell operated without the aid of electron mediators.

Thermally Conductive, Electrical Insulating, Optically Transparent Bi-Layer Nanopaper.

Cellulose nanofiber (CNF) from abundant and renewable wood is an emerging material with excellent mechanical, chemical, and optical properties. Transparent nanopaper made of CNF (CNF-nanopaper) could potentially replace plastics in electronics due to its excellent optical transparency, mechanical strength, and biodegradability. However, CNF-nanopaper normally has a low thermal conductivity and poor stability in increasing temperatures, which is not suitable for long-term stability and reliability in devices.

Transfer-Free Growth of Multilayer Graphene Using Self-Assembled Monolayers.

Large-area graphene needs to be directly synthesized on the desired substrates without using a transfer process so that it can easily be used in industrial applications. However, the development of a direct method for graphene growth on an arbitrary substrate remains challenging. Here, we demonstrate a bottom-up and transfer-free growth method for preparing multilayer graphene using a self-assembled monolayer (trimethoxy phenylsilane) as the carbon source.

Self-Powered Human-Interactive Transparent Nanopaper Systems.

Self-powered human-interactive but invisible electronics have many applications in anti-theft and anti-fake systems for human society. In this work, for the first time, we demonstrate a transparent paper-based, self-powered, and human-interactive flexible system. The system is based on an electrostatic induction mechanism with no extra power system appended.

Liquid slip on a nanostructured surface.

We explored a liquid slip, referred to as the Navier slip, at liquid-solid interface. Such a slip is provoked by the physicochemical features of the liquid-solid system. The goal of this study was to investigate the effect of a nanoengineered surface structure on liquid slip by fabricating the self-assembly structure of nano Zinc oxide (n-ZnO).

Enhanced light extraction of nonpolar a-plane (11-20) GaN light emitting diodes on sapphire substrates by photo-enhanced chemical wet etching.

The extraction efficiency of nonpolar a-plane (11-20) GaN LEDs on sapphire substrates has been enhanced by selectively etching the mesa sidewall faces and the n-type GaN surfaces with photoenhanced chemical wet etching. Submicron-sized trigonal prisms having prismatic planes of {1-100} were clearly displayed on the n-type GaN surfaces as well as the sidewall face after 5 min etching at 60 degrees C. The radiation patterns have shown that more light is extracted in all directions and the output powers of surface textured a-plane GaN LEDs have increased by 25% compared with control samples.