Self-powered, flexible, and instantly dynamic multi-color electroluminescence device with bi-emissive layers for optical communication

Self-powered alternating current electroluminescence (ACEL) displays own distinctive preponderance in artificial electronic skins and information communication in the internet of things (IoT). However, their limited color options, i.e., monochrome or static multicolor, hinder their versatility. In this paper, we introduce an instantly dynamic multi-color display system that combines integrated bi-emissive layer ACEL with a dual-cells triboelectric nanogenerator (DC-TENG). Our bi-emissive ACEL device includes ZnS:Cu and ZnS:Mn phosphors blended in polydimethylsiloxane (PDMS) to achieve green and orange emissions, respectively. The DC-TENG consists of a polytetrafluoroetylene (PTFE) film and two copper tapes, generating an open-circuit voltage of ∼270 V and a short-circuit current of ∼2.5 μA, which is sufficient to power the bi-emissive layer ACEL device. By pressing the DC-TENG cell, the self-powered display system instantly renders green, orange and warm white emissions, making these dynamic multi-color responses useful as information units in the IoT. The self-powered optical communication system is demonstrated by transmitting the word “CHINA”. Our study may provide a new approach for developing self-powered multi-color display systems and expands their potential applications in information communication for the IoT.