Infrared spectroscopy is demonstrated to sensitively detect electronic excitations in 1-nm-wide wires made of indium. The polarization-dependent spectra measured at room temperature show a strong broadband plasmonic absorption feature in the direction parallel to the wires, while in the perpendicular direction the wires stay nearly transparent in the same spectral range. At 88 K the wires do not show this broadband absorption anymore, but instead, several interband-transition features arise for both polarizations, in agreement to the gap opening of the metal-to-insulator transition as known for this one-dimensional structure.

We report on the reduction of band gap in Bi0.5(Na0.82-xLixK0.18)0.5(Ti0.95Sn0.05)O3 from 2.99 eV to 2.84 eV due to the substitutions of Li+ ions to Na+ sites. In addition, the lithium substitution samples exhibit an increasing of the maximal polarizations from 21.8 to 25.7 μC/cm2. The polarization enhancement of ferroelectric and reduction of the band gaps are strongly related to the Li substitution concentration as evaluated via the electronegative between A-site and oxygen and tolerance factor. The results are promising for photovoltaic and photocatalytic applications.

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Metal nanowires with proper length give strong antenna-like plasmonic resonances in the infrared. Their resonance spectrum is a sensitive measure not only of their geometry but also of their conductivity as we will show for lead nanoantennae here.

Sodium manganese oxide (Na x MnO 2 ) has attracted much attention as cathode materials for alkaline ion battery due to the ability of the fast charge and discharge of Na + , in particular in nanoscale. We report on the synthesis of Na x MnO 2 nanowires via hydrothermal synthesis route from Mn 2 O 3 and NaOH solution. The morphological observation indicates that the obtained Na 0.44 MnO 2 nanowires with diameters of about 20 nm -30 nm, length up to several micrometers were formed by this process. The electrochemical properties of fabricated materials were investigated by means of cyclic voltammetry technique and show that sodium manganese oxide (Na x MnO 2 ) is a promising material used for the alkaline ion battery.