Fabrication of C-doped WO₃ nanoparticle cluster arrays from PS-b-P4VP for room temperature H₂ sensing

C-doped WO3 based room temperature hydrogen sensors including nanoparticle cluster arrays and nanorods were successfully prepared by a PS-b-P4VP template based method. AFM, TEM and XPS are used to characterize the structure and composition of the samples. Analyses indicate that the C-doped WO3 nanoparticle cluster arrays are arranged in a beautiful hexagonal configuration and they are interconnected by a superthin carbon film. The cluster with sizes in the range of 12-15 nm is composed of several 4-6 nm nanocrystallites. An improved room temperature hydrogen response is found on C doped WO3 nanoparticle cluster arrays, whose response sensitivity (S), response time and recovery time are 114, 162 s and 108 s, respectively. Three aspects are used to analyze the reasons for the improved room temperature hydrogen response; the study indicates the great potential of the block copolymer based method to prepare excellent WO3 based room temperature H2 sensors.