Organic Tribotronic Transistor for Contact-Electrification-Gated Light-Emitting Diode

Abstract

Tribotronics is a new field about the devices fabricated using the electrostatic potential created by contact electrification as a "gate" voltage to tune/control charge carrier transport in semiconductors. In this paper, an organic tribotronic transistor is proposed by coupling an organic thin film transistor (OTFT) and a triboelectric nanogenerator (TENG) in vertical contact-separation mode. Instead of using the traditional gate voltage for controlling, the charge carrier transportation in the OTFT can be modulated by the contact-induced electrostatic potential of the TENG. By further coupling with an organic light-emitting diode, a contact-electrification-gated light-emitting diode (CG-LED) is fabricated, in which the operating current and light-emission intensity can be tuned/controlled by an external force-induced contact electrification. Two different modes of the CG-LED have been demonstrated and the brightness can be decreased and increased by the applied physical contact, respectively. Different from the conventional organic light-emitting transistor controlled by an electrical signal, the CG-LED has realized the direct interaction between the external environment/stimuli and the electroluminescence device. By introducing optoelectronics into tribotronics, the CG-LED has open up a new field of tribophototronics with many potential applications in interactive display, mechanical imaging, micro-opto-electro-mechanical systems, and flexible/touch optoelectronics.