Electrospinning of Flexible Poly(vinyl alcohol)/MXene Nanofiber-Based Humidity Sensor Self-Powered by Monolayer Molybdenum Diselenide Piezoelectric Nanogenerator

Abstract

A flexible piezoelectric nanogenerator (PENG) based on 2D single-layer MoSe 2 flake on polyethylene terephthalate was fabricated. A high-performance flexible poly(vinyl alcohol)/MXene (PVA/MXene)-based humidity sensor was fabricated by electrospinning. The PVA/MXene composite-based humidity sensor was self-powered by MoSe 2 PENG and exhibited excellent properties. Abstract Two-dimensional material has been widely investigated for potential applications in sensor and flexible electronics. In this work, a self-powered flexible humidity sensing device based on poly(vinyl alcohol)/Ti 3 C 2 T x (PVA/MXene) nanofibers film and monolayer molybdenum diselenide (MoSe 2 ) piezoelectric nanogenerator (PENG) was reported for the first time. The monolayer MoSe 2 -based PENG was fabricated by atmospheric pressure chemical vapor deposition techniques, which can generate a peak output of 35\xa0mV and a power density of 42\xa0mW m −2 . The flexible PENG integrated on polyethylene terephthalate (PET) substrate can harvest energy generated by different parts of human body and exhibit great application prospects in wearable devices. The electrospinned PVA/MXene nanofiber-based humidity sensor with flexible PET substrate under the driven of monolayer MoSe 2 PENG, shows high response of ∼40, fast response/recovery time of 0.9/6.3\xa0s, low hysteresis of 1.8% and excellent repeatability. The self-powered flexible humidity sensor yields the capability of detecting human skin moisture and ambient humidity. This work provides a pathway to explore the high-performance humidity sensor integrated with PENG for the self-powered flexible electronic devices.