WO3nanowires on carbon papers: electronic transport, improved ultraviolet-light photodetectors and excellent field emitters

Abstract

Single-crystalline WO₃ nanowires were synthesized on carbon papers through a chemical vapor deposition process without using any catalysts. WO₃ nanowire field-effect transistors (FETs) were constructed to discuss the mechanism of electronic transport based on a thermal-activation model and a displacive transition. Photoconductive measurements showed that individual WO₃ nanowire photodetector was sensitive to the ultraviolet light, and the photoresponse was further improved using WO₃ nanowires on carbon papers, demonstrating significantly shortened response and decay times, and enhanced stability. Field-emission measurements showed that WO₃ nanowires were excellent field-emitters: an ultralow turn-on field of 1.8 V μm⁻¹ and a threshold field of 3.3 V μm⁻¹, and a high field-enhancement factor of 6.9 × 10³. These results indicate that present unique WO₃ nanowires on carbon papers are promising candidates for constructing high-performance electronic and optoelectronic devices.