Simulations of Benzene and Hydrogen-Sulfide Gas Detector Based on Single-Walled Carbon Nanotube over Intrinsic 4H-SiC Substrate

Abstract

Carbon nanotubes (CNTs)-based sensors have gained significant importance due to their tremendous electrical and physical attributes. CNT-based gas sensors have high sensitivity, stability, and fast response time compared to that of solid-state sensors. On exposure to a large variety of organic and inorganic compounds, the conductivity of CNT changes. This change in electrical conductivity is being used as a detection signal to detect different target molecules. Hydrogen-sulfide and benzene are hazardous gases that can cause serious health issues in humans. Therefore, it is mandatory to detect their presence in industrial and household environments. In this article, we simulated CNT-based benzene and hydrogen-sulfide sensor with a nanoscale semiconductor device simulator—Quantumwise Atomistix Toolkit (ATK). The change in the device density of states, electric current, and photocurrent in the presence of target molecules have been calculated. The change in photocurrent in the presence of target molecules has been proposed as a novel detection mechanism to improve the sensor selectivity and accuracy. This change in photocurrent as well as electric current in the presence of target molecules can be used simultaneously as detection signals. Our intension in the future is to physically fabricate this simulated device and use photocurrent as well as electric current as detection mechanisms.

First Principal Simulation Study of Human Body Compatible Molecular Single Electron Transistors

“…7, it can be seen that the DOS plot for the SET configuration of riboflavin (vitamin B2) and folic acid (vitamin B9), were significantly different from all other DOS curves, and these two devices have many abrupt spikes in energy states and sharp energy peaks in their DOS plot. These sharper energy peaks show the higher conductivity of these SET devices [80]. The applicability among the overall energy and the gate capability for the other 6 molecules is nonlinear.…”

Highly Selective Detection of Hydrogen Sulfide by Simple Cu-CNTs Nanocomposites

“…Being efficient adsorbents, carbon nanotubes (CNTs) are used for detecting pollutants with the aim of their consequent removal from air. Different types of CNTs have been synthesized and applied for this purpose [7][8][9][10].…”