Lead ions detection using CVD-grown ReS2-FET with the facilitation of a passivation layer

• Published in: Applied surface science Vol. 661; p. 160061
• Main Authors: Devnath, Anupom, Venkatesan, Annadurai, Alimkhanuly, Batyrbek, Lee, Seunghyun
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.07.2024
• Subjects: Amplifier circuit; Heavy-metal detection; Passivation layer; ReS2 FET-based sensor; Selectivity; Heavy-metal detection; Amplifier circuit; Selectivity; ReS2 FET-based sensor; Passivation layer
• ISSN: 0169-4332; 1873-5584
• DOI: 10.1016/j.apsusc.2024.160061

[Display omitted] •Dendrite ReS2, a flower-like TMD with a higher surface-to-volume ratio.•A passivation layer on ReS2 surfaces, significantly boosts device sensitivity.•Ensure high sensitivity (2 nM) for Pb2+ ions with fast response (1.1 s).•A reproducible, selective, and repeatable sensing performance.•A novel metal ion sensing amplifier circuit.•Low-cost integration with portable devices and industrial electronics. Field-effect transistor (FET)-based heavy-metal detection is garnering attention due to its heightened sensitivity, affordability, convenient fabrication, and portability. Flower-like rhenium disulfide (ReS2) offers potential for high-performance FET sensors, but direct exposure of channel materials to the ionic solution without a passivation layer results in multiple signals arising from the ionic transmission, doping impact, and gating effect. Introducing a passivation layer to the channel surface enhances sensor sensitivity without compromising device performance, ensuring conductance changes are primarily due to the gating effect. Here, a large surface area of Chemical Vapor Deposition (CVD)-grown vertically aligned ReS2 is employed in the FET-based sensor, and the utilization of the HfO2 layer is to isolate analytes from the elements of the conducting channel. For real-time lead monitoring in a water environment, it exhibits strong electrical stability, an impressive LoD (≈2 nM), a rapid response time (≈1.1 sec), and notable selectivity. Additionally, sensing operations are characterized by developing a unique amplifier circuit by integrating the fabricated sensor, contributing to advancements in sensor integration to detect hazardous metals in industrial electronics. These results underscore the potential for enhancing the performance of ion-sensitive FETs through structural optimization and improvements to the fundamental sensor mechanism.