Electrochemical Generation of Mesopores and Residual Oxygen for the Enhanced Activity of Silver Electrocatalysts.

The development of stable and efficient electrocatalysts is of key importance for the establishment of a sustainable society. The activity of a metal electrocatalyst is determined by its electrochemically active surface area and intrinsic activity, which can be increased using highly porous structures and heteroatomic doping, respectively. Herein, we propose a general strategy of generating mesopores and residual oxygen in metal electrocatalysts by reduction of metastable metal oxides using AgO electrodeposited onto carbon paper as a model system and demonstrating that the obtained multipurpose porous Ag electrocatalyst has high activity for the electroreduction of O and CO.

Self-Regulation of Infrared Using a Liquid Crystal Mixture Doped with Push-Pull Azobenzene for Energy-Saving Smart Windows.

A self-regulating liquid crystal (LC) smart window whose reflectance changes with ambient conditions is demonstrated. Thermally or optically induced switching between the transparent state and a near-infrared (NIR) reflective state can be used for energy-saving windows. Reflection of NIR can reduce the energy used for cooling, while remaining transparent to visible light.

Mechanical characteristics of metal nanoparticle thin film on flexible substrate exposed to saline solution.

The robust and reliable mechanical characteristics of metal nanoparticle (NP) thin films on flexible substrates are important because they operate under tensile, bending, and twisting loads. Furthermore, in wearable printed electronics applications, salty solutions such as sweat and seawater can affect the mechanical reliabilities of devices. In this paper, we investigated the effect of sodium chloride (NaCl) solutions on silver (Ag) NP thin films on flexible polymer substrate.

Bottom-up Cu filling of annular through silicon vias: Microstructure and texture.

Microstructural and morphological evolution during bottom-up Cu filling of annular through silicon vias (TSV) in a CuSO-HSO-Cl-poloxamine electrolyte is examined. Deposition proceeds in two distinct stages beginning with a passive-to-active state transition on the via sidewalls whose depth and ultimate thickness depends on the polymer flux. Growth is conformal or tapered with columnar grains whose width and texture differ between the outer and inner sidewalls of the annulus due to area reduction and expansion respectively.

A multi-pair electrode based impedance sensing biopsy needle for tissue discrimination during biopsy process.

We demonstrate the biopsy needle integrated with multi-pair electrode based impedance sensing device for biological tissue discrimination. The impedance sensing biopsy needle has several pairs of electrodes which enable the selective tissue analysis during biopsy process. In order to verify the usefulness of the device, we demonstrate the conductance measurement of various saline solutions and the real-time conductance monitoring of soft elastomeric materials during the needle insertion.

A stretchable strain sensor based on a metal nanoparticle thin film for human motion detection.

Wearable strain sensors for human motion detection are being highlighted in various fields such as medical, entertainment and sports industry. In this paper, we propose a new type of stretchable strain sensor that can detect both tensile and compressive strains and can be fabricated by a very simple process. A silver nanoparticle (Ag NP) thin film patterned on the polydimethylsiloxane (PDMS) stamp by a single-step direct transfer process is used as the strain sensing material.

Tensile characteristics of metal nanoparticle films on flexible polymer substrates for printed electronics applications.

Metal nanoparticle solutions are widely used for the fabrication of printed electronic devices. The mechanical properties of the solution-processed metal nanoparticle thin films are very important for the robust and reliable operation of printed electronic devices. In this paper, we report the tensile characteristics of silver nanoparticle (Ag NP) thin films on flexible polymer substrates by observing the microstructures and measuring the electrical resistance under tensile strain.

Interfacial toughening of solution processed Ag nanoparticle thin films by organic residuals.

Reliable integration of solution processed nanoparticle thin films for next generation low-cost flexible electronics is limited by mechanical damage in the form of delamination and cracking of the films, which has not been investigated quantitatively or systematically. Here, we directly measured the interfacial fracture energy of silver nanoparticle thin films by using double cantilever beam fracture mechanics testing. It was demonstrated that the thermal annealing temperature and period affect the interfacial fracture energy.

Direct micro/nano metal patterning based on two-step transfer printing of ionic metal nano-ink.

We present a direct metal patterning method by a two-step transfer printing process of non-particle, ionic metal nano-ink solution. This fabrication method allows a simple direct patterning of various micro/nanoscale metallic structures. Complex structures such as multilayer line arrays, patterns along non-flat topologies, and micro/nanoscale hybrid patterns can be achieved by using this process.