The fundamental role of the solid electrolyte interphase (SEI) layer in preventing dendritic Li growth has been investigated in solid-state batteries.

Hierarchical nanostructures with SnO(2) backbones and ZnO branches are successfully prepared in a large scale by combining the vapor transport and deposition process (for SnO(2) nanowires) and a hydrothermal growth (for ZnO). The ZnO nanorods grow epitaxially on the SnO(2) nanowire side faces mainly with a four-fold symmetry. The number density and morphology of the secondary ZnO can be tailored by changing the precursor concentration, reaction time, and by adding surfactants. Photoluminescence (PL) properties are studied as a function of temperature and pumping power. Such hybrid SnO(2)-ZnO nanostructures show an enhanced near-band gap emission compared with the primary SnO(2) nanowires. Under the optical excitation, a UV random lasing is observed which originates from the hierarchically assembled ZnO branches. These three-dimensional nanostructures may have application potentials as chemical sensors, battery electrodes, and optoelectronic devices.

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In contrast to typical metals, carbon nanotubes are shown to form a unique Schottky barrier contact with semiconductors wherein a gate field can modulate not only the band bending in the semiconductor but also the height of the barrier. These phenomena are exploited to enable two new device architectures: a vertical field‐effect transistor (figure) and a vertical light‐emitting transistor.

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Two new alternating low bandgap copolymers from benzodithiophene and benzotriazole units, namely poly{4,8-bis(2-ethylhexyloxy)benzo [1,2-b; 3,4-b]dithiophene-2,6-diyl-alt-2-octyl-4,7di(thiophen-2-yl)-2H-benzo [d][1,2,3]triazole-5 0 ,5 00 -diyl} (PBDTDTBTz) and poly{4,8-bis(2ethylhexyloxy)benzo [1,2-b;3,4-b]dithiophene-2,6-diyl-alt-2-dodecylbenzotriazole-4,7-diyl} (PBDTBTz), were designed and synthesized by a typical Stille coupling polymerization method. The copolymers were characterized by thermogravimetric analysis, UV-vis absorption and cyclic voltammetry. PBDTDTBTz and PBDTBTz possess moderate molecular weights and excellent thermal properties with a 5% weight loss temperatures (T d ) around 300 C. They exhibited good optical absorption, with peaks at 527 nm and 562 nm in the film state, respectively. Photovoltaic properties of the copolymers blended with [6,6]-phenyl-C61-butyric acid methyl ester (PC 61 BM) or [6,6]-phenyl-C71-butyric acid methyl ester (PC 71 BM) as electron acceptors, were investigated. The photovoltaic device with the PBDTDTBTz/PC 71 BM shows a power conversion efficiency of 1.7% with a short circuit current density of 4.5 mA cm À2 and a good fill factor of 0.62, while PBDTBTz demonstrated a moderate power conversion efficiency of up to 1.4%, under the illumination of AM 1.5, 100 mW cm À2 with a device structure of ITO/PEDOT: PSS/polymer: PC 71 BM (1 : 4)/Ca/Al. All the above information highlighted that this kind of the copolymers is promising for the application of polymer solar cells.

The white-light long-lasting phosphor CaAl2O4:Dy3+ was prepared and investigated. The white-light afterglow spectra under the irradiation of 254 or 365nm are comprised of the blue light emission and the yellow light emission, originating from the transitions of F9∕24→H15∕26, F9∕24→H13∕26 in the 4f9 configuration of Dy3+. The afterglow can last 32min for the best sample with Dy-doped concentration of 2at.%. The decay curve and the thermoluminescence curve show to be a second-order process. Thermoluminescence curves exhibit a complicated structure in the range of 230–450K with the peaks at 244, 280, 310, and 346K. The two thermoluminescence bands peaking above room temperature have corresponding traps with the depths of 0.54 and 0.61eV, which are responsible for the afterglow emission at room temperature. This work provides a promising approach for the development of white-light long-lasting phosphor.

Lattice dynamical, dielectric, and thermodynamic properties of β-Ga2O3 are investigated by first principles. The calculated phonon frequencies for the Raman-active and the infrared-active modes are assigned. The phonon dispersion curves along high symmetry lines in the Brillouin zone and the phonon density of states are also calculated. The electronic and static dielectric tensors are calculated. The calculated static dielectric constants are much larger than the electronic constants, showing the rather strong ionic contributions to static dielectric constants. These calculated results are in a good agreement with available experimental values. The thermodynamic functions are calculated by using the phonon density of states.