Flexible in-plane graphene oxide moisture-electric converter for touchless interactive panel

Harvesting energy from nature have attracted much attentions especially the direct energy conversion from other power sources (e.g. light, heat, mechanical movement, moisture) into practical electricity. However, many of existing devices always rely heavily on external metal electrodes, and their rigid structure restrains further applications in portable touchless electronics or perceptual artificial skins. Herein, we demonstrate flexible in-plane moisture-electric converter (IPMEC) based on graphene oxide (GO) film for novel touchless interactive platform. An appreciable electric output voltage (similar to 70 mV) and high electrical current density (12 mA cm(-2)) can be autonomously generated with ambient moisture variation on this IPMEC. The planar configuration and integrative laser reduced GO electrodes of IPMEC renders it highly flexibility, and greatly promotes the touchless interface formation between this device and biological moisture sources (e.g., human finger). Based on this, diverse touchless devices have been developed including finger position annunciator for smart artificial skin, touchless switches and even handwriting panel. This work will provide a new pathway for the development of flexible moisture-electric converters and applications in touchless interactive platform for biomimetic or smart electronics.