Selective hydrogenation of WO_3 for erasable conducting circuit

摘要

Hydrogenation of tungsten trioxide (WO_3) can effectively modulate its material property and induce the insulator-metal transition. Due to the insertion of H atoms, a transparent WO_3 film will normally change to deep-blue color because of its pronounced electrochromism. More importantly, the electronic structure will also convert from an insulator to a metallic state, showing greatly improved conductivity with an enhancement of up to six orders of magnitude. Combined with the traditional lithography route, selective hydrogenation of WO_3 in microscale size is achieved based on the electron-proton synergistic effect in an acid solution. This metal-like conductive H-doped WO_3 can be used as an erasable microcircuit since it will be recovered to a WO_3 insulator by annealing in air at an appropriate temperature. The current study demonstrates a facile way to fabricate erasable WO_3 conducting micro/nanowires, or even microcircuits, by selective hydrogenation under ambient conditions, which should be extended to other oxide materials for functional applications.