Influence of the Carbon Nanotube Density on Building Sensitive and Noise-Free Volatile Organic Compound Sensors

This paper presents a study on peptide-functionalized carbon nanotube (CNT) chemiresistors, where the effect of CNT density is investigated to optimize their gas sensing performances. While previous CNT density studies mostly focused on sensor performance and its reliability testing from a handful of devices, we systemically control CNT density and investigate more than 30 devices in terms of sensitivity, noise, and signal-to-noise ratio (SNR). The results exhibit that the higher CNT resistance results in 1) higher sensitivity, 2) higher noise, and 3) lower SNR. These results indicate that careful control of CNT density is crucial for optimizing CNT-based gas sensors.