Reduced graphene oxide layered WO thin film with enhanced electrochromic properties.

The electrochromic (EC) properties of inorganic-organic hybrids of tungsten oxide/reduced graphene oxide (WO/rGO) thin films were examined. Using hydrothermal method WO nanorods were deposited on a conducting Indium-doped tin oxide (ITO) glass substrate. In succession, the reduced graphene oxide thin film was coated on WO thin film using improved Hummers method. The structural, morphological, optical, and electrochromic responses of WO, rGO, and WO/rGO films are illustrated. Compared with pure WO film, WO/rGO composite film demonstrates improved EC performance because of enhanced double insertion/extraction of ions and electrons. It realizes a large optical modulation (58.8% at 633 nm) with a significant increase in Coloration Efficiency (CE) and EC stability.