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In this study, we developed a photodetector and humidity sensor based on zinc oxide nanowires (ZnO NWs) with CsPbBr3 perovskite quantum dots (PQDs). PQDs are ideally suited to semiconductor sensors due to their excellent optoelectronic properties, including the high carrier mobility, high absorption coefficient, and effective charge transfer at heterojunctions. The ZnO NWs were created via chemical bath deposition, and PQDs were created via a one-step injection method. I–V curves revealed that the current leakage of PQD/ZnO NWs was lower than that of ZnO NWs. PQD/ZnO NWs also generated a larger number of photogenerated carriers, which improved sensor responses, regardless of the illumination wavelength. Under UV illumination, the photocurrent of both structures decreased with an increase in relative humidity; however, under green light illumination, the photocurrent of PQD/ZnO NWs increased with humidity. This study also investigated the optical properties of the two structures as candidate sensor mechanisms. [ABSTRACT FROM AUTHOR]

In this paper, a single-step chemical bath deposition method was developed for the growth of novel aluminium (Al)-doped zinc oxide nanostructures (NSs) comprising a dual-layer of nanorods/nanowalls. This particular mesoporous structure can accommodate a larger number of ChOx molecules than is possible in a traditional nanorod array. The formation of this dual-layer of NSs depends largely on the content of Al ions and reaction time. A cholesterol biosensor was constructed using these NSs as supporting materials for cholesterol oxidase loading. The device achieved sensitivity of 93.82\mu \textA/\textmMcm^2 within a linear-range of 1.3–13 mM. [ABSTRACT FROM PUBLISHER]

This paper reports on the fabrication of ZnO nanowalls for use as an electron collecting layer (ECL) in CH 3 NH 3 PbI 3 perovskite solar cells (PSCs). Two-dimension ZnO nanowalls were grown using a low-temperature chemical bath method with a thin Al film as a seed layer. We compared electron collecting layers based on nanowalls and sol–gel derived ZnO thin film in PSCs and sought to identify the mechanism underlying the collection of electrons. The proposed ZnO nanowalls achieved a fill factor significantly higher than that of ZnO thin films, which translated into a remarkable improvement in power conversion efficiency, reaching 13.6% under AM 1.5G illumination. [ABSTRACT FROM AUTHOR]

Abstract: Al-doped ZnO (AZO) films with a thickness of ∼400nm were prepared by sputtering on glass substrates for use as transparent anodes of organic light-emitting diodes (OLED) devices. The operation voltages (at 100cd/m2) of OLED devices with AZO and ITO anode materials were 10.5 and 5.5V, respectively. The maximum luminance output of the AZO device was 6450cd/m2 (achieved at 12.5V) and that of the ITO device was 9830cd/m2 (achieved at 10.5V). We demonstrate that a hole-only device method can be used to estimate the suitability of AZO and ITO anodes in the OLED devices and to verify experimental results. The AZO thin films with low price and non-toxicity may be suitable as alternative anodes in OLED devices under high voltage. [Copyright &y& Elsevier]

A hybrid resistance switching device consisting of ZnO nanorods embedded in an insulating polymethylmethacrylate (PMMA) heterostructure sandwiched between a transparent conductive film and an Al electrode is proposed. The current-voltage characteristics of the device are discussed in terms of the formation and rupture of its conductive filaments. The hybrid device shows stable electrical bistable behaviors after more than 200 resistance-switching cycles. The hybrid ZnO nanorod/PMMA device presented in this work has potential applications in the field of bistable random access memory devices. [ABSTRACT FROM AUTHOR]

Li-doped zinc oxide (L0.03Z0.97O) thin films are deposited onto Pt/Ti/SiO2/Si substrates via the radio frequency magnetron sputtering method. The structure evolution with annealing temperature of the predominantly (002)-oriented Li-doped ZnO (LZO) films after in-situ post-annealing process is determined. The largest values of the piezoelectric coefficient (d33) and the remnant polarization (Pr) (22.85 pm/V and 0.655 μC/cm2, respectively) are obtained for LZO films post-annealed at 600 °C, which can be attributed to the predominant (002)-oriented crystalline structure, the release of intrinsic residual compressive stress, and less non-lattice oxygen. [ABSTRACT FROM AUTHOR]

Abstract: The advantages of using an anode buffer layer of ZnO on the electro–optical properties of organic light emitting devices (OLEDs) are reported. ZnO powders were thermal-evaporated and then treated with ultra-violet (UV) ozone exposure to make the ZnO layers. The turn-on voltage of OLEDs decreased from 4V (4.2cd/m2) to 3V (3.4cd/m2) and the power efficiency increased from 2.7lm/W to 4.7lm/W when a 1-nm-thick ZnO layer was inserted between indium tin oxide (ITO) anodes and α-naphthylphenylbiphenyl diamine (NPB) hole-transporting layers. X-ray and ultra-violet photoelectron spectroscopy (XPS and UPS) results revealed the formation of the ZnO layer and showed that the work function increased by 0.59eV when the ZnO/ITO layer was treated by UV-ozone for 20min. The surface of the ZnO/ITO film became smoother than that of bare ITO film after the UV-ozone treatment. Thus, the hole-injection energy barrier was lowered by inserting an ZnO buffer layer, resulting in a decrease of the turn-on voltage and an increase of the power efficiency of OLEDs. [Copyright &y& Elsevier]