This paper demonstrates the potential of a new photoanode material Zn-doped SnO 2 nanoflower for efficient dyesensitized solar cells. The nanoflower structure is synthesized using a hydrothermal method and is shown to have electron mobility higher than that of the conventional titania photoanode. The overall power conversion efficiency for the Zn-doped SnO 2 nanoflower dye-sensitized solar cell reaches 3.00% with a V oc of 0.78 V and increases to 6.78% after TiCl 4 treatment. Electrochemical impedance spectroscopy measurement showed that the Zn-doped SnO 2 nanoflower film has a large intrinsic electron mobility that favors the fast charge transport. This work shows that Zn-doped SnO 2 nanoflower material is a most interesting material and has good potential for application in solar cells.

Semiconductor ZnO nanotube arrays have been synthesized by direct electrochemical deposition from aqueous solutions into porous anodic alumina membranes. Scanning electron microscopy and transmission electron microscopy indicate that large-area and highly ordered nanotube arrays have been obtained. X-ray diffraction and selected-area electron diffraction analyses show that the as-synthesized nanotubes are polycrystalline. Photoluminescence spectra of the ZnO nanotube arrays show that a violet peak and a blue peak are centered at 414 and 464 nm, respectively. The ordered polycrystalline ZnO nanotube arrays may find potential applications in optoelectronic and sensor devices. The growth mechanism and the electrochemical deposition process are discussed.

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Uniform CdS/ZnO core/shell nanowires are hydrothermally synthesized using a two‐step process and assembled into a photodetector and a NO2 optoelectronic sensor for the first time. The corresponding photodetector exhibits a fast, reversible, and stable optoelectronic response with a rise time of ∼26 ms, a decay time of ∼2.1 ms and a stability of over 5 months. The remarkable photosensitivity and fast photoresponse are attributed to the formation of a heterojunction structure between CdS and ZnO, which greatly inhibits the recombination of photoinduced electrons and holes. The CdS/ZnO core/shell nanowires also show an excellent visible‐light‐activated gas sensing performance towards ppb‐level NO2 at room temperature. The responses range from 6.7% to 337% toward NO2 concentrations of 5 to 1000 ppb. It is found that the sensitivity of the NO2 sensor is dependent on the illuminated light intensity with a maximum value at 0.68 mW/cm2. The sensing mechanisms of the CdS/ZnO nanowires under visible‐light irradiation and the influence of light intensity are also discussed. The present CdS/ZnO core/shell nanowire not only benefits the fabrication of efficient photodetectors, but also makes the instant, optically controlled sensing of ppb‐level NO2 gas possible.