Multifunctional black phosphorus pressure sensors with bending angle monitoring and direction recognition characteristics

• Published in: Nanoscale Vol. 16; no. 12; pp. 5999 - 69
• Main Authors: Chen, Jiangtao, Ma, Guobin, Wang, Xinyi, Song, Tiancheng, Zhu, Yirun, Jia, Shuangju, Zhang, Xuqiang, Zhao, Yun, Chen, Jianbiao, Yang, Bingjun, Li, Yan
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 21.03.2024
• Subjects: Artificial intelligence; Bending; Feature recognition; Handwriting; Motion stability; Nanomaterials; Phosphorus; Photovoltaic cells; Portable equipment; Power consumption; Pressure sensors; Sensors; Solar cells; Thin films; Wrist
• ISSN: 2040-3364; 2040-3372
• DOI: 10.1039/d3nr05372e

Flexible pressure sensors, an important class of intelligent sensing devices, are widely explored in body-motion and medical health monitoring, artificial intelligence and human-machine interaction. As a unique layered nanomaterial, black phosphorus (BP) has excellent electrical, mechanical, and flexible characteristics, which make it a promising candidate for fabricating high-performance pressure sensors. Herein, hierarchically structured BP-based pressure sensors were constructed. The sensors exhibit high sensitivity, stability and a wide sensing range and respond to various human motions including finger pressure, swallowing, and wrist bending. The sensors can identify different handwriting processes with featured signals. In particular, benefiting from the unique structure of loose-dense layers, the sensors show a distinctive response to bending angles and directions, revealing a characteristic of direction recognition. This feature facilitates the sensors to monitor human motions. The sensors have been successfully powered by a home-made Cu 2 ZnSn(S,Se) 4 thin-film solar cell, which demonstrates the sustainability, flexibility and low power consumption of integrated devices. This work offers a strategy to construct hierarchically structured pressure/strain sensors with direction recognition and provides further insights into manufacturing portable sensing devices for realistic and innovative applications. A multifunctional pressure sensor based on black phosphorus nanoflakes is fabricated, and it shows good bending angle monitoring and direction recognition characteristics.