Here we demonstrate the preparation and improved hydrogen monitoring properties based on p-NiO/n-SnO 2 heterojunction composite nanofibers via the electrospinning technique and calcination procedure. NiO/SnO 2 heterojuction composite nanofibers were spin-coated on the ceramic tube with a pair of Au electrodes for the detection of hydrogen. Extremely fast response-recovery behavior (∼3s) has been obtained at the operable temperature of 320 °C, based on our gas sensor, with the detection limit of approximate 5 ppm H 2 . The role of the addition of NiO into the SnO 2 nanofibers and the sensing mechanism has also been discussed in this work.

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In this study, AlPO 4 nanowires were coated on the surfaces of LiV 3 O 8 powders successfully. The influence of the coating on the electrochemical behavior of LiV 3 O 8 was discussed. The surface morphology was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). AlPO 4coated LiV 3 O 8 cathode materials exhibited distinct surface morphology. AlPO 4 nanowires were clearly observed on the surfaces of LiV 3 O 8 . The structural changes of the cathode materials before and after coating were revealed by X-ray diffraction spectroscopy (XRD). The 1 wt % AlPO 4 coating has been found to reduce the capacity fade of LiV 3 O 8 significantly. Cyclic voltammetry (CV) shows that the characteristic phase transitions during cycling exhibited by the uncoated material are suppressed by the 1 wt % AlPO 4 coating. This behavior implies that AlPO 4 inhibits structural change of LiV 3 O 8 during cycling. In addition, the AlPO 4 coating on LiV 3 O 8 significantly suppresses the increase of charge-transfer impedance (R ct ) in cycling. Comparative data for the coated and uncoated materials are presented and discussed.