Pt-decorated NiWO4/WO3 heterostructure nanotubes for highly selective sensing of acetone

Abstract

The heterostructured NiWO4/WO3 nanotubes (Ni/W NTs) were synthesized by using a facile self-assembly method on the sacrificial polystyrene (PS) nanofibers templates. Then, the Pt-decorated NiWO4/WO3 (Pt@Ni/W) composite NTs were obtained through using an ultrasonic mixing method. The experimental results display that the order of gas-sensing performance is Pt@Ni/W>Ni/W>WO3. The 2wt.%Pt@Ni/W-5 NTs indicate the supreme acetone-sensing response (Rair/Rgas=58.4 at 100×10−6) at 375 °C, which is 10.6 and 1.53 times that of the WO3 and NiWO4/WO3 NTs, respectively. Additionally, the 2wt.%Pt@Ni/W-5 NTs also exhibit the dramatically high selectivity toward acetone against ethanol, methanal, methanol, NH3 and toluene. The Pt-decorated Ni/W NTs show the excellent responsivity and stability toward acetone, which is ascribed to the construction of heterostructured NiWO4/WO3 and the spill-over effect of Pt nanoparticles.