Graphene quantum dots (GQDs) were synthesized and incorporated with polyethylenedioxythiophene:poly(4-styrenesulfonate) (PEDOT:PSS), Ag nanowires (AgNWs) to form a composite that can be used for enhancement of relative humidity (RH%) sensing. The composite films contained bulk heterojunctions of AgNW/GQD and AgNW/PEDOT:PSS. The sensors made from the composites responded well to relative humidity in a range from 10% to 50% at room temperature. With an AgNWs content ranging from 0.2 wt.% to 0.4 wt.% and 0.6 wt.%, the sensitivity of the relative humidity sensing devices based on AgNWs-doped GQDs+PEDOT:PSS composites was increased from 5.5% to 6.5 % and 15.2 %, respectively. The response time of the composite sensors was much improved due to AgNWs doping in the composites. For the 0.6 wt.% AgNWs-doped GQDs+PEDOT:PSS films, the best value of the recovery time was found to be of 30 s.

Zn 1−x Sn x O NRs/ITO composite photocatalytic films were fabricated by the hydrothermal method. A concentration of Sn dopant in Zn 1−x Sn x O nanorods (NRs) was varied from 0% to 7%. The structural and surface morphology characteristics of Zn 1−x Sn x O NRs/ITO composite photocatalytic films were investigated by X-Ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. In addition, photocatalytic properties of synthesized materials were evaluated by degradation rates of Rhodamine-B aqueous solutions under UV light irradiation. The SEM results indicated that, with an increasing concentration of Sn dopant in Zn 1−x Sn x O NRs/ITO, the effective surface areas were declined by an exponential decay function and the reduction was negligible as the Sn doping concentration was higher than 3%. With the similarity in effective surface area, the contribution of Sn in the enhancement of the photocatalytic activity of Zn 0.93 Sn 0.07 O NRs/ITO is clearly observed with 41% improvement in comparison to ZnO NRs/ITO.