Capacitive and resistive response of humidity sensors based on graphene decorated by PMMA and silver nanoparticles

Rahim, Ishrat, Shah, Mutabar, Khan, Afzal, Luo, Jingting, Zhong, Aihua, Li, Min, Ahmed, Rashid, Li, Honglang, Wei, Qiuping and Fu, Yong Qing (2018) Capacitive and resistive response of humidity sensors based on graphene decorated by PMMA and silver nanoparticles. Sensors and Actuators B: Chemical, 267. pp. 42-50. ISSN 0925-4005

[img]
Preview
Text
Second Minor Revised manuscript.pdf - Accepted Version

Download (643kB) | Preview
Official URL: https://doi.org/10.1016/j.snb.2018.03.069

Abstract

In this paper, we reported comparative study of the humidity characteristics of graphene/silver nanoparticles composite (Gr-AgNps) and graphene/silver nanoparticles/PMMA composite (Gr-AgNps-PMMA) based efficient humidity sensors. Aqueous solution of Gr-AgNps and Gr-AgNps-PMMA was drop casted over interdigitated copper electrodes with 50 μm gap embedded in the substrates in dust free environment. The band gap obtained from the UV-vis spectra for Gr-AgNps and Gr-AgNps-PMMA based humidity sensors was 4.7 and 4.1 eV respectively. The capacitive and resistive humidity response was studied using LCR meter (GW Instek817). Apparent increase in capacitance was observed (100-10,000 nF) with the increase in the humidity percentage (30-95%RH) at lower frequencies for both the sensors. Resistance of the sensors dropped to zero as the humidity level is increased from 30 to 95%RH in the chamber. The devices were tested for real time stability and for fast response/recovery time. Both the devices showed an excellent stability and response by recording their resistance and capacitance respectively. A lagging of RH decreasing response from RH increasing response was observed at 500 Hz frequency for both the sensors depicted from the hysteresis curve. The humidity response of Gr-AgNps was comparatively better than that of the Gr-AgNps-PMMA based humidity sensors.

Item Type: Article
Uncontrolled Keywords: Humidity sensors; graphene; thin film; response/recovery; band gap
Subjects: F100 Chemistry
F200 Materials Science
Department: Faculties > Engineering and Environment > Mathematics, Physics and Electrical Engineering
Depositing User: Becky Skoyles
Date Deposited: 21 Mar 2018 09:54
Last Modified: 14 Mar 2019 08:00
URI: http://nrl.northumbria.ac.uk/id/eprint/33815

Actions (login required)

View Item View Item

Downloads

Downloads per month over past year

View more statistics


Policies: NRL Policies | NRL University Deposit Policy | NRL Deposit Licence