A new kind of nitrite sensor based on 3C-SiC whisker electrode was fabricated to electrochemically determine nitrite. Powder X-ray diffraction, field emission scanning electron microscope, and transmission electron microscopy reveal SiC whiskers are cubic single crystalline with some microtwins. The prepared SiC whisker electrode is examined for the electrochemical detection of nitrite under neutral condition using cyclic voltammetry and differential pulse voltammetry techniques. The results demonstrate that SiC whisker electrode fast responses toward nitrite with a detection limit of 3.5 × 10 −6 mol L −1 , which is comparable to the values reported in the recent literatures. The synthesized electrode is also successfully applied to determine nitrite in tap water.

In this study, the reaction between industrial grade molybdenum trioxide powders and activated carbon has been investigated in order to produce industrial grade molybdenum dioxide (MoO2). Effects of activation carbon addition and reaction temperature on the product compositions are both illustrated. Increasing the reaction temperature can significantly improve the reaction rate. It is difficult for them to react completely when the temperature is lower than 550 °C. However, industrial grade MoO2 powders can be obtained when the temperature is up to 650 °C. It is also found that there is no intermediate product Mo4O11 formed during the reaction process of MoO3 by activated carbon, which is different from the case of hydrogen reduction of MoO3 to MoO2. The crystalline size of the obtained MoO2 becomes very small relative to that of the raw material MoO3.

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