Molybdenum-carbide-graphene composites for paper-based strain and acoustic pressure sensors

Abstract Paper-based pressure/strain sensors could have potential wide applications with wearable features in disposable products. In this study, molybdenum carbide-graphene (MCG) composites with porous and stacking micro-structures are fabricated on top of the paper substrate to act as piezo-resistivity strain/pressure sensors. As a strain sensor, this paper-based device can detect not only the amplitude and frequency of applied strain but also the direction as tensile or compressive deformation. The gauge factors are 73 and 43 for tensile and compressive strain, respectively, with demonstration example in detecting and recognizing human body motions. As a pressure sensor, this MCG-based paper device has high sensitivity to weak pressure signals such as sounds by distinguishing the seven piano notes. Our study provides a simple strategy for developing paper-based electronics with unique properties toward practical applications.