A flexible piezoresistive pressure sensor based on a perovskite MAPbBr3 nanocrystal-embedded polymer composite

Abstract

The development of flexible pressure sensors based on perovskite is still largely unexplored as the existing sensors are mainly inflexible and do not meet the evolving needs of various applications. In this study, a sandwich-structured polymer pressure film embedded with MAPbBr₃ nanocrystals was prepared, and its porosity can be achieved by adjusting the nanocrystal content. XPS analysis demonstrated a strong interaction between the MA⁺ and the fluorine group CF²⁻ in PVDF during the synthesis process, which enabled the two to form a homogeneous and stable conductive polymer composite. The prepared sensor displayed a high sensitivity (0.744 kPa⁻¹ in the pressure range of 0–60 kPa), a wide linear range (0–60 kPa), and a short response/recovery time (102.05 ms/87.75 ms). In addition, the sensing material maintains good hydrophobicity with a water contact angle of 125.32°, which allows it to work in a humid environment. Furthermore, a wearable prototype device was fabricated for facial expression, pulse signal, blowing and joint bending motion monitoring. This study might lay the foundation for a flexible perovskite-based pressure sensor for a wide range of applications in multiple fields.