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In this work, a novel sensor for detecting hydrogen peroxide was constructed on the base of nanotubular TiO 2 and platinum nanoparticles. The morphology, structural, and electrochemical properties of the Pt/TiO 2 nanocomposite electrodes were characterized by SEM, XRD and electrochemical methods. With an operating potential of þ 0.3 V versus Ag/AgCl, the sensor produces catalytic oxidation currents at the nanocomposite electrode, which can be exploited for quantitative determinations. The amperometric signals are linearly proportional to hydrogen peroxide concentration in the range 4 Â 10 À6 to 1.25 Â 10 À3 M. The regression equation is I (mA) ¼ 0.85 c (mM) þ 0.16 with a correction coefficient of 0.997. At a signal-to-noise ratio of 3, a detection limit of 4.0 mM H 2 O 2 can be observed for the nanocomposite electrode. In addition, the sensor has a good stability and reproducibility. The construction process is simple and inexpensive. The results demonstrated that nanotubular TiO 2 exhibits great prospect for developing a class of ideal and novel bioreactors and biosensors.

In order to improve the poor solvent resistance and poor temperature resistance caused by traditional sizing agents, crystalline poly(ether ether ketone) (PEEK) is introduced to the interfacial phases of carbon fiber (CF) reinforced PEEK composites by a soluble precursor named PEEK‐1,3‐dioxolane. By changing the soluble precursor molecular weight and concentration in the sizing solution, the content of PEEK coated on the CF fiber surface can be controlled and the different interfacial properties of the PEEK composites can be obtained. The results shows that, with this method, crystalline PEEK can be completely coated on the CF surface, and the interfacial shear strength of the PEEK composites increases from 43.42 to 83.13 MPa. Due to none of any soluble compounds in the PEEK composites, the interfacial layer is well preserved under organic solvents and hygrothermal conditions, and the interfacial shear strength (IFSS) of the PEEK composites maintained above 85.4% and 90.44%, respectively. Scanning electron microscope clarifies that the mechanism of interface enhancement comes from a better wetting of crystalline PEEK on the fiber surface. Additionally, the sizing system of this investagation has the potential commercial value because of no toxic reagent (such as 2,4,5‐trichloro‐1‐hydroxy‐benzene or concentrated sulfuric acid) is required during sizing.

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