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ZnO nanorods and graphene foam were synthesized via hydrothermal synthesis and chemical vapor deposition, respectively. Hybrid of ZnO nanorods and graphene nanosheets was prepared by ultrasonic treatment. The hybrid was sprayed onto the ITO glass. The hybrid was characterized by scanning electron microscopy, X-ray diffraction, and Raman spectroscopy. The electrochemical properties of the hybrid were measured by cyclic voltammetry and differential pulse voltammetry. The results show that the diameter and length of ZnO nanorods are ~ 50 nm and 5 μm, respectively. Graphene nanosheets with high quality are made up of few layers and the sheet size is ~ 2 μm. The sensitivity of the hybrid for detection of uric acid is 0.3 μM μA−1 cm−2 in the range of 5~80 μM. The electrode can accurately detect uric acid in the presence of ascorbic acid. Meanwhile, the electrode also shows good repeatability and stability.

Novel side-heating gas sensor based on ZnO nanorod circular arrays was firstly fabricated by hydrothermal treatment assisted with a kind of simple dip-coating technique. The structure and morphologies of ZnO nanorods were characterized by X-ray diffraction (XRD), Scanning Electron Microscope (SEM), respectively. XRD result indicates that the obtained ZnO nanorods have good crystalline with the hexagonal wurtzite structure. SEM result indicates that ZnO nanorod arrays are vertically growth on the surface of ceramic tube of side-heating sensor with controlled diameter and length, narrow size distribution and high orientation. The gas sensing properties of ZnO nanorod circular arrays are also evaluated. Comparative to the sensor based on scattered ZnO nanorods responding to 25 ppm H2, CO, C6H5CH3 and C2H5OH gas, respectively, the sensing values of high orientation gas sensor are generally increased by 5%. This novel sensor has good application promising for the fabrication of cost effective and high performance gas sensors.

2024Al composites reinforced by aluminum borate whiskers with different ZnO coating contents were fabricated by squeeze casting. The effects of the coating contents and T6 heat-treatment on the bending properties of the composites were investigated. The results show that the bending properties of the composite firstly increase and later decline with increasing ZnO coating contents of the whiskers. T6 heat-treatment of the composites can further improve the bending properties of the composites. On the analysis of fractographs, the fracture mechanisms of the composites under bending were also investigated.

ZnO coating of the aluminum borate whiskers was prepared by sol–gel and 2024Al composite reinforced by the ZnO coated aluminum borate whiskers was fabricated by squeeze casting. Tensile properties and aging behaviors of the composite were investigated. The results show that the ZnO coating of the whiskers reacts with molten 2024Al during squeeze casting and simultaneously a layer of uniform MgAl 2 O 4 forms at the interface. The tensile properties of the composite are the largest after the solid solution treatment at 490 °C for 2 h and the aging treatment at 170 °C for 8 h. The ZnO coating of the whiskers significantly changes the aging behaviors of the aluminum borate whiskers reinforced 2024Al composite.

A three-dimensional (3D), macroporous and highly conductive graphene foam (GF) was synthesized by atmospheric pressure chemical vapor deposition (CVD). The morphologies of the GF were characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The structure of the GF was investigated by X-ray diffraction (XRD) and Raman spectroscopy. The GF prepared by CVD was then transferred onto ITO coated glass, acting as an electrode, to detect dopamine (DA) and ascorbic acid (AA) by electrochemical methods. The results show that the GF exhibits high selectivity for the detection of DA and AA. It also shows high sensitivity for detection of DA with the lower detection limits of ∼2.0 nM in the linear response up to ∼10 µM. This demonstrates the free-standing GF provides a promising platform as a 3D biosensing material.

Novel hierarchical ZnO nanomaterials with castellated and turriform morphologies were successfully synthesized by ultrasonic assisted hydrothermal route. The morphology and structure of products were characterized by scanning electron microscopy and X-ray diffraction, respectively. The results show that as-prepared castellated ZnO microrods have six-equal axis symmetry features with the length of 2–4 μm and the diameter of about 1 μm, and ZnO with turriform morphology has radical branch structure with the diameter ranging from 500 to 700 nm. It is found that initial alkaline concentration of the solution plays a crucial role in determining two kinds of hierarchical morphologies by etching ZnO crystal during hydrothermal process. A possible formation mechanism of castellated and turriform ZnO microstructures is also proposed. Gas sensing of hierarchical ZnO to different gases was also examined. The result indicates turriform ZnO sensor has fast response properties and excellent selective resolution capability to C2H5OH gas.