Polyvinylpyrrolidone/multiwall carbon nanotube composite based 36° YX LiTaO3 surface acoustic wave H2 gas sensor

Poly-vinyl-pyrrolidone (PVP) is one of the actylene chemistry products founded by Prof Walter Reppe. In most cases, PVP usually presents as an essential auxiliary, not an active substance itself . Until recently, He et al. has reported the application of PVP fibers as H₂ gas sensor. Extending from the reported investigation, this work shows the gas sensing properties of PVP/MWNTs composite/36° YX LiTaO₃ SAW device. The surface morphology of the electrospun PVP/MWNTs composite was investigated via scanning electron microscopy (SEM). Results show that by adding 1.525g of PVP into the solution, both fibres and beads are observed in random directions, in planes parallel to the substrate. Whereas, no fibres were observed by synthesizing 1.025g of PVP/MWNTs onto SAW device. However, MWNTs are clearly seen inside the PVP particles and distributed evenly in the particles. The sensing performance of the PVP/MWNTs composite based SAW sensors were investigated by placing the sensors in the gas chamber.