Monodisperse Al-Doped ZnO/Perovskite Nanocapsule.

We developed monodisperse ZnO nanocapsules and atmospheric N plasma was used to develop a ZnO-organic nanocomposite. To test the seal of the ZnO nanocapsule, the halide perovskite CH3NH3PbBr3 was used as the filler. Al atoms were doped into ZnO nanorods to increase the conductivity of ZnO nanorods. A green emission peak located at 535 nm was observed in the nanocapsules with a 410 nm excitation because of the free-exciton recombination of CH3NH3PbBr3. The Al-doped ZnO (AZO)/CH3NH3PbBr3 nanocapsules was further tested under using a three-electrode photoelectrochemistry cell. AZO/CH3NH3PbBr3 nanocapsule arrays yield an elevated photocurrent of approximately 0.2 mA/cm2 at 1 V versus Ag/AgCl under air mass 1.5 (AM 1.5), almost 1.5 times larger than that of the AZO nanorod arrays. The photo-current stability of AZO/CH3NH3PbBr3 nanocapsule arrays photoelectrode is better than that of AZO nanorod arrays under a repeated on/off light test. This confirmed that the AZO/CH3NH3PbBr3 nanocapsules had been successfully sealed and that the degradation of CH3NH3PbNBr3 was thus dramatically reduced. Our study yields a novel platform for nanoscale optical and optoelectronic devices or for delivery of highly toxic drugs.

Indium-Zinc-Tin-Oxide Film Prepared by Reactive Magnetron Sputtering for Electrochromic Applications.

This paper reports on the fabrication of indium-zinc-tin-oxide (IZTO) transparent conductive film deposited by direct current (DC) reactive magnetron sputtering. The electrical, structural, and optical properties of IZTO film were investigated by Hall measurement, X-ray diffraction (XRD), and optical transmission spectroscopy with various sputtering powers. The IZTO film prepared used power at 100 W showed the lowest resistivity of 5.2 × 10-4 Ω cm. To accomplish rapid switching and high optical modulation, we have fabricated an electrochromic device (ECD) consisting of an working electrode (WO3 electrode film deposited on IZTO/ITO/glass) and a counter-electrode (Pt mesh) in 0.2 M LiClO4/PC liquid solution. The device demonstrated an optical contrast of 44% and switching times of 4.6 s and 8.1 s for the coloring and bleaching state, respectively, at the wavelength of 550 nm.

Electrochromic and optical properties of tungsten oxide films deposited with DC sputtering by introducing hydrogen.

Research was undertaken to investigate the electrochromic and optical properties of tungsten oxide (WO3) films deposited by introducing hydrogen with a direct current (DC) and pulsed DC sputtering. The results show that WO3 films have optimum electrochromic properties at a hydrogen flow of 4 and 3 sccm for DC and pulsed DC, respectively. In the Raman spectra, the peak intensity increased with the increase of hydrogen flow at both 770 cm1 and 950 cm(-1) peaks, which resulted in bonds of W(6+)-O and W(6+)=O, respectively. Simultaneously, the transmittance (ΔT550 nm) variations were 65.6% and 64.4%, and the average transmittance (ΔT400-500 nm) variations were 56.7% and 56.4% for DC and pulsed DC, respectively. The bleached/colored ability of the cyclic voltammograms (CVs) was DC>pulsed DC, and the resistances of AC impedance were pulsed DC>DC.

Transparent conductive oxide layer with monolayer closed-pack Al-doped ZnO spheres and their application to a-Si thin-film solar cells.

We report a new (to the best of our knowledge) transparent conductive oxide (TCO) layer with a monolayer of closed-pack Al-doped ZnO (AZO) spheres partly embedded in an AZO thin film. The average transmittance and haze ratio in the wavelength range of 380-800 nm achieves 65% and 55%, respectively, when AZO spheres with a diameter of 500 nm are embedded in a thickness of 240 nm AZO thin films. The a-Si thin-film solar cell with a regular p-i-n TCO structure is demonstrated. Under air mass 1.5 global illumination, conversion efficiencies of 5.6%, a fill factor of 0.55, V(oc) of 0.81 V, and a J(sc) of 2.44 mA/cm² are obtained. The Letter helps us to open up potential applications of a new TCO in advanced solar cells and light-emitting diodes.

Haze ratio enhancement using a closely packed ZnO monolayer structure.

A ZnO thin-film that comprised a ZnO monolayer close-packed structure embedded in ZnO sol-gel was fabricated. The structure contained ZnO spheres of various sizes. At normal incidence, the mean optical transmittance of the thin-film was 60% in the visible region when the structure contained spheres with a diameter of 300 nm. An average haze ratio of 80% was obtained from the thin-film when the structure was formed using 500 nm-diameter spheres. The thin-film exhibits broad-band transparency and a high haze ratio. It can be used as a light-trapping structure in an ultrathin solar cell.