From Janus triboelectric interface to energy-autonomous sensing system: An asymmetric design

The asymmetric and anisotropic conductive properties of Janus membranes is drawing considerable attention for the development of self-powered wearable electronics because it is a potential platform for endowing sustainable power sources such as triboelectric nanogenerator with high performance and multifunctionality . Herein, we prepared ultrathin electrically anisotropic Janus membranes by mixing liquid metal (LM) nanoparticles with a hydroxyethyl cellulose (HEC) suspension. The density deposited LM-HEC Janus film shows both excellent insulating properties on the HEC side and directly writable and conductive path properties on the LM side. A folding structured triboelectric nanogenerator (FS-TENG) was thus developed based on the insulating property of the HEC side for Morse code encrypted communication as well as Braille typewriters. Besides, a tactile sensor with visible light feedback functions was constructed using the functional circuit that was built on the conducting LM side, which promotes the design of wearable energy-autonomous sensing system by intrinsically integrating the self-power function with visual sensing parts. The simple preparation method applied in this study shed new light on the design and fabrication of flexible electronics that are based on Janus films.