Solution-processed flexible TiS2/organic superlattice films may find applications in powering wearable electronics.

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Semiconductor-based gas sensors that use n-type WO3 or p-type Co3O4 powder were fabricated and their gas sensing properties toward NO2 or NO (0.5–5 ppm in air) were investigated at 100 °C or 200 °C. The resistance of the WO3-based sensor increased on exposure to NO2 and NO. On the other hand, the resistance of the Co3O4-based sensor varied depending on the operating temperature and the gas species. The chemical states of the surface of WO3 or those of the Co3O4 powder on exposure to 1 ppm NO2 and NO were investigated by diffuse reflectance infrared Fourier transform (DRIFT) spectroscopy. No clear differences between the chemical states of the metal oxide surface exposed to NO2 or NO could be detected from the DRIFT spectra.

Thin films of the intercalated organic-inorganic hybrids (PPy) x MoO 3 (PPy: polypyrrole) have been prepared by an ex-situ intercalation process. The host MoO 3 films were first deposited on LaAlO 3 (LAO) single-crystal substrates by using a CVD method followed by the intercalation of PPy into the MoO 3 films. The preparation of highly b-axis oriented MoO 3 films is crucial to prepare the (PPy) x MoO 3 films. The (PPy) x MoO 3 thin film shows a semiconducting-like transport with an activation energy of 0.21 eV. The (PPy) x MoO 3 thin films show a distinct response to VOCs by increasing their electrical resistivity and exhibit higher sensitivities to polar analytes such as formaldehyde and acetaldehyde, whereas it showed almost no response to toluene and benzene.

Quantitative texture analysis of grain-aligned [ Ca 2 Co O 3 ] 0.62 [ Co O 2 ] ceramics processed by the reactivetemplated grain growth method Highly grain-aligned Ca 3 Co 4 O 9 and (Ca 2.7 Sr 0.2 La 0.1 )(Co 3.9 Cu 0.1 )O 9 ceramics were prepared by the magnetic alignment technique, and then treated by a spark plasma sintering process to increase their bulk densities. Thermoelectric properties were investigated from room temperature to 700°C in air. Grain alignment is effective in lowering the electrical resistivity and has no obvious influence on the Seebeck coefficient, thus resulting in enhancement of the thermoelectric power factor. Substitution of Sr, La and Cu does not appreciably change the electrical resistivity and Seebeck coefficient, but significantly reduces the thermal conductivity.