Carbon nanotube cross-linked phosphorus-doped MXene for capacitive pressure microsensors

• Published in: Journal of materials chemistry. A, Materials for energy and sustainability Materials for energy and sustainability, 2024-08, Vol.12 (31), p.19891-19898
• Main Authors: Yang, Wenshuai, Zhu, Shifan, Hao, Chenyang, Ji, Tailong, Liu, Yuanyuan, Wang, Yuqiao
• Format: Article
• Language: English
• Subjects: Capacitance; Carbon; Carbon nanotubes; Chemical vapor deposition; Crosslinking; Electron distribution; External pressure; Flexibility; Ion transport; MXenes; Nanotechnology; Nanotubes; Phosphorus; Self-assembly; Specific capacity; Supercapacitors; Vacuum filtration
• ISSN: 2050-7488; 2050-7496
• DOI: 10.1039/d4ta04029e

The extreme mechanical flexibility, integration and wearability of one-dimensional carbon-based cross-linked two-dimensional MXenes can exactly meet the rapid development of microelectronic technology and medical microdevices, thereby achieving miniaturization and multi-functionality. Herein, a pressure microsensor was assembled using micro-supercapacitors of phosphorus-doped MXene cross-linked by carbon nanotubes. The carbon nanotube cross-linked phosphorus-doped MXene (P-MXene/CNT) is prepared by chemical vapor deposition and electrostatic self-assembly. The interdigital electrodes are obtained through mask-assisted vacuum filtration to integrate symmetrical micro-supercapacitors using a gel electrolyte. P-doping regulates the electron distribution of the MXene and improves the specific capacity. The P-MXene is cross-linked by carbon nanotubes to alleviate the self-stacking effect for accelerated ion transport. The P-MXene/CNT based planar micro-supercapacitor shows desirable mechanical flexibility and integrability with an extraordinary area capacitance of 162.4 mF cm −2 , an energy density of 32.9 μW h cm −2 , and a long-term cycling stability up to 91.3% after 10 000 cycles. The pressure microsensor illustrates an outstanding sensitivity toward external pressure and ensures an accurate and continuous detection of human body motions. The flexibility, integration and wearability of one-dimensional carbon-based cross-linked two-dimensional MXenes can exactly meet the rapid development of microelectronic technology, thereby achieving miniaturization and multi-functionality.