Room Temperature Ionic Liquid-Gated Carbon Nanotube FETs for Stable Hydrogen Sensing at Elevated Temperatures
Year: 2025
Type: article
Abstract: A novel hydrogen sensor, harnessing the synergy of room temperature ionic liquid (RTIL) and carbon nanotube field-effect transistors (CNT FETs), is proposed to improve the stability and long-term reliability of gas sensors. Utilizing RTIL as an electrolyte gate dielectric enhances sensitivity and markedly improves stability under elevated temperatures and harsh environmental conditions. The sensor maintains a low subthreshold slope (SS ≈ 100 mV/dec) and a stable on/off ratio (>104) after long-term operation at 80°C. At 1000 ppm H2, it exhibits a strong response of 86%, with rapid response/recovery times of 76/230 s. Selectivity measurements show negligible responses to 10 ppm NO2, NH3, and H2S (<16%), indicating good anti-interference performance. Nernst equation analysis highlights the role of the RTIL/metal interface electric double layer (EDL) in modulating sensing process. Additionally, the T90 response time of the sensor decreases from 246 s at 23°C to 76 s at 80°C, demonstrating accelerated hydrogen diffusion at higher temperatures, consistent with a diffusion-controlled model. The sensor was also applied for real-time hydrogen monitoring during lithium-ion battery thermal runaway, where it quickly and accurately detected hydrogen leakage, showcasing its potential in elevated temperature environments. These findings underscore the key role of the RTIL gate in improving sensor performance and reliability, providing both theoretical and practical support for the future use of RTIL-CNT FET gas sensors.
Source: ACS Omega
Authors: Yuzhang Liu, Zinan Zhi, Shuhuan Liu, Junyi Qian, Kai Huang, Zhongqiu Hua
Institutions: Xiangtan University, Peking University
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,935
Awards: 晶圆级碳基场效应型VOCs气体传感器的研究, G3808306184
OpenAlex ID: W4411400084
