Smart Semiconductor-Heterojunctions Mechanoluminescence for printable and wearable sports light sources

Abstract

Mechanoluminescence (ML) materials, which directly convert mechanical energy into light emission, have emerged as an emerging class of light-emitting materials with various applications.Although significant progress has been made in the development of new ML materials and devices, their practical application is limited by their low intensity and homogenously structured host structures. Thus, multiple-structured host ML materials with high ML intensity and reproducibility are needed, particularly for wearable and printable ML light sources with high brightness.In this study, various Mn-doped ternary heterojunction ML materials, CaZnOS-ZnS-SrZnOS, are synthesised by high-temperature solid-phase reactions, and their luminescence properties are systematically tested. The result indicates that the ternary heterojunction materials have a higher ML intensity over 60 times stronger than the state-of-art SrZnOS: Mn2+, which is currently the brightest sample we have obtained. ML linearly depends on the magnitude of the applied force. Based on the synthesised ternary ML heterojunctions, repetitive self-driving luminescence of the zipper is achieved for the first time through powder modification and inlay; the clothes composed of our prepared zippers are pulled and bent when worn on the body to emit bright visible light. Additionally, a Velcro that can achieve light emission is developed; it provides a new idea for the development of wearable flexible self-luminous devices in the future. Simultaneously, movement-driven stress luminous printable objects that can be printed on the surface of various commodities or their packaging are demonstrated. The preparation of self-driven, battery-free, and electrode-free stress luminescence wearable low light sources has an important application trend, which can avoid the interference of the circuit and improve the stability of the devices, thus promising a wide range of applications in smart wear, energy-saving displays, safety and rescue, robotic skin, and information security.