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Porous carbon is a pivotal material for electrochemical applications. The manufacture of porous carbon has relied on chemical treatments (etching or template) that require processing in all areas of the carbon/carbon precursor. We present a unique approach to preparing porous carbon nanospheres by inhibiting the pyrolytic condensation of polymers. Specifically, the porous carbon nanospheres are obtained by coating a thin film of ZnO on polystyrene spheres. The porosity of the porous carbon nanospheres is controlled by the thickness of the ZnO shell, achieving a BET-specific area of 1,124 m²/g with a specific volume of 1.09 cm³/g. We confirm that under the support force by the ZnO shell, a hierarchical pore structure in which small mesopores are connected by large mesopores is formed and that the pore-associated sp³ defects are enriched. These features allow full utilization of the surface area of the carbon pores. The electrochemical capacitive performance of porous carbon nanospheres was evaluated, achieving a high capacitance of 389 F/g at 1 A/g, capacitance retention of 71% at a 20-fold increase in current density, and stability up to 30,000 cycles. In particular, we achieve a specific area-normalized capacitance of 34.6 µF/cm², which overcomes the limitations of conventional carbon materials. [ABSTRACT FROM AUTHOR]

Inverse opal (IO) films with meso-porous structures hold promise as high-performance electrodes for various photo electrochemical devices because of their high specific area as well as their fully connected pore structure. A great challenge to their use is obtaining an intact film of meso-scale colloidal crystals as a template. Here, using the plate-sliding coating method coupled with hot air flow, we successfully deposited mesoscale colloidal crystals onto the substrate. A TiO2 meso-scale IO (meso-IO) with 70 nm pores was then successfully fabricated via atomic layer deposition of TiO2 and subsequent removal of the template. As a photo electrochemical electrode, the meso-IO structure exhibits enhanced charge transport properties as well as a high specific area. Moreover, dye-sensitized solar cells fabricated using the meso-IO electrode exhibit a higher photocurrent and cell efficiency than a cell constructed using a conventional TiO2 nano-particle electrode. This meso-IO film provides a new platform for developing electrodes for use in various energy storage and conversion devices. [ABSTRACT FROM AUTHOR]

A 4 × 4 matrix model with three degrees of freedom is proposed as a means for controlling microvibrations and applied to an electromagnetic isolator. The model was derived from an assumption based on small- and low-frequency vibrations. The coordinates of the 3 DOF was composed of the 4 variables, representing a vertical position, pitch, roll, and a proof term. The coordinates were calculated from the 4 position sensors in the isolator and formulated into a 4 × 4 matrix, which possesses inversive full rank. The electro-magnetic isolator was built for a simulated machine in semiconductormanufacturing and consisted of a heavy surface plate, sensors, amps, a controller, and air springs with electromagnets. The electromagnets are installed in a pneumatic chamber of the individual air spring. The performance of the 3 DOF model was experimented and compared with that of a 1 DOF model in an impact test. The settling time in the result was reduced to 25%. [ABSTRACT FROM AUTHOR]