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Cu(In, Ga)Se2 solar cells are the representative of high efficient thin-film solar cell with energy conversion efficiency of over 22%. However, nowadays, top electrodes of solar cells gradually become the performance limitation for optimized devices. The Al-doped ZnO thin film is widely used as a transparent top electrode in Cu(In, Ga)Se2, but there are still some techniques and electrical property issues. In this letter, we establish a ZnO/Ag/ZnO:Al multilayer top electrode, composed of ZnO nanorod arrays, Ag nanoparticles, and ZnO:Al thin films. Such multilayer top electrode was applied on Cu(In, Ga)Se2 thin-film solar cells and the devices yield a higher efficiency from 6.79% to 8.52%. Importantly, we also propose that the enhanced electronic carrier concentration in such ZnO/Ag/ZnO:Al top electrode aids the performance of solar cells. Therefore, well-designed ZnO-based top electrodes offer the opportunity to remove the bottleneck of improving the solar cell efficiency. [ABSTRACT FROM PUBLISHER]

High quality ZnO nanowires (NWs) were grown on a graphene layer by a hydrothermal method. The ZnO NWs revealed higher uniform surface morphology and better structural properties than ZnO NWs grown on SiO2/Si substrate. A low dark current metal–semiconductor–metal photodetector based on ZnO NWs with Au Schottky contact has also been fabricated. The photodetector displays a low dark current of 1.53 nA at 1 V bias and a large UV-to-visible rejection ratio (up to four orders), which are significantly improved compared to conventional ZnO NW photodetectors. The improvement in UV detection performance is attributed to the existence of a surface plasmon at the interface of the ZnO and the graphene. [ABSTRACT FROM AUTHOR]

In this letter, we investigated oxygen ion concentration gradient method, which can manipulate the set voltage of zinc oxide-doped silicon oxide resistance random access memory. To analyze this method, the ITO/ZnO:SiO2/ZnOx/TiN bilayer structure was proposed and discussed. On the basis of the oxygen ions migration effect, the set voltage of the oxide-based resistive memory can be altered after a bias stress at the TiN electrode. The physical mechanism of the special resistive switching characteristics were depicted by the interaction between [O2−] gradient driving force and electrical force. [ABSTRACT FROM AUTHOR]

Abstract: Three dimensional hierarchical ZnS coated ZnO nanoclusters have been successfully synthesized through modifying ZnO nanocolumn method. The morphological, structural, and compositional properties of the ZnS coated ZnO nanoclusters are systematically studied by scanning electron microscopy, X-ray diffractometry, Fourier transform infrared spectroscopy, and X-ray photoelectron spectroscopy. It is shown that the wurtzite crystal structure of ZnS has been formed after ZnO nanocolumns were dipped into SCNH2 solution for 1h. Moreover, a simple growth mechanism has been proposed to interpret the formation of the ZnS coated ZnO nanoclusters based on the results of Fourier transform infrared spectroscopy and X-ray photoelectron spectroscopy. The obtained ZnS coated ZnO nanoclusters are expected to have a broad range of potential applications in electronics, optoelectronics, and spintronics. [Copyright &y& Elsevier]

Abstract: ZnO thin films deposited on Si substrate were irradiated by nanosecond KrF excimer laser at 248nm wavelength. To investigate the mechanism of the laser interaction with ZnO film, a focused laser beam has been used. The effect of laser energy on the film has been systemically investigated by scanning electron microscopy, Raman spectral and X-ray photoelectron spectroscopy. An obvious laser thermal effect has been observed at the incident laser power intensity less than 2.5J/cm2. Further, with the increase of laser power intensity, novel ZnO nano-platelets have been found on the surface because laser induced plasma caused electron–ion emission from the surface. Our results show that the higher intensity of laser power distributes abundance of ZnO nano-platelets and nano-platelets have potential applications in electronics, optoelectronics, and spintronics. [Copyright &y& Elsevier]