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We used microelectromechanical system techniques to fabricate a miniature ascorbic acid fuel cell (AAFC) equipped with a microchannel for the circulation of ascorbic acid solution (AAS). The fuel cell was fabricated on a flexible polyimide substrate, and a porous carbon-coated aluminum (Al) anode with the dimensions of 2.8 ×1 mm 2 and a porous carbon-coated Al cathode with the dimension of 2.8 ×10 mm 2 were fabricated using photolithography and screen-printing techniques. The porous carbon was deposited by screen-printing carbon-black ink onto the Al electrode surfaces in order to increase the effective electrode surface areas and to absorb more enzymes (bilirubin oxidase) on the cathode surface. No enzyme was deposited on the carbon coated anode surface. The microchannel with a dimension of 3 ×11× 0.2 mm 3 was fabricated using a hot-embossing technique. The maximum power of 0.60 µW at 0.58 V, with a corresponding power density of 1.96 µW/cm 2 , was realized by introducing a 200 mM concentrated AA solution at the flow rate of 30 ml/min at room temperature. No degradation of the anode and cathode was observed up to the radius of curvature of 7.5 mm, which suggests the flexibility of the AAFC.

In the system Zr0,, ZrTiO, solid solutions prepared by the simultaneous hydrolysis of zirconium and titanium alkoxides crystallize at low temperatures from amorphous materials between 30 and 70 mol% TiO,. As zirconium is substituted for titanium, the solid solutions can be indexed in an orthorhombic unit cell with a and c decreasing linearly from 0.4832 to 0.4778 nm and from 0.5063 to 0.5002 nm, respectively, and b increasing linearly from 0.5401 to 0.5478 nm. The volume of the unit cell decreases continuously with increasing TiO, content. At higher temperatures the solid solutions decompose into ZrTiO, and either ZrO, (monoclinic) or TiO, (rutile), depending on the starting composition. [

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Graphene is promising for next-generation devices. However, one of the primary challenges in realizing these devices is the scalable growth of high-quality few-layer graphene (FLG) on device-type wafers; it is difficult to do so while balancing both quality and affordability. High-quality graphene is grown on expensive SiC bulk crystals, while graphene on SiC thin films grown on Si substrates (GOS) exhibits low quality but affordable cost. We propose a new method for the growth of high-quality FLG on a new template named “hybrid SiC”. The hybrid SiC is produced by bonding a SiC bulk crystal with an affordable device-type wafer and subsequently peeling off the SiC bulk crystal to obtain a single-crystalline SiC thin film on the wafer. The quality of FLG on this hybrid SiC is comparable to that of FLG on SiC bulk crystals and much higher than of GOS. FLG on the hybrid SiC exhibited high carrier mobilities, comparable to those on SiC bulk crystals, as anticipated from the linear band dispersions. Transistors using FLG on the hybrid SiC showed the potential to operate in terahertz frequencies. The proposed method is suited for growing high-quality FLG on desired substrates with the aim of realizing graphene-based high-speed devices.