Nowadays, humidity sensors have become essential in numerous applications. However, there are several problems while using them for humidity detection, such as low sensitivity, delayed response and recovery times, less stability, and narrow humidity detection ranges. Here, we demonstrate for the first time a highly sensitive chemiresistive sensor for low-level humidity detection in ambient atmosphere by introducing graphene oxide (GO) and doped GO (Li-doped GO and B-doped GO) as a thin film in a facile manner. The sensitivity, repeatability, and stability studies show that thin film-based fabricated humidity sensors are unprecedently efficient in the detection of different percentages of humidity from 11 to 97% at room temperature. The incorporation of doping into GO induces a dramatic change in the sensing behavior of the base film (undoped GO). This allows the sensor to be used in a variety of applications such as humidity sensing, which we validate through our experiment with a “cheap and readily available” recognition system.
The arch-shaped single electrode based triboelectric nanogenerator (TENG) is fabricated using thin film of reduced graphene oxide nanoribbons (rGONRs) with polyvinylidene fluoride (PVDF) polymer used as binder to effectively convert mechanical energy into electrical energy. The incorporation of rGONRs in PVDF polymer enhances average surface roughness of rGONRs/PVDF thin film. With the combination of the enhancement of average roughness and production of functional groups, which indicate improve charge storage capacity of prepared film. Furthermore, the redox peaks obtained through cyclic voltammetry were identified more in rGONRs/PVDF composite in comparison to pristine rGONRs to confirm charge transfer capability of film. Herein, the output performance was discussed experimentally as well as theoretically, maximum voltage was obtained to be 0.35 V. The newly designed TENG to harvest mechanical energy and opens up many new avenues of research in the energy harvesting applications.
1 December 2016 in International Journal of Hydrogen Energy