Boosted photoresponsivity using silver nanoparticle decorated TiO₂ nanowire/reduced graphene oxide thin-film heterostructure

Abstract

Here, we report on the fabrication and use of a silver (Ag) nanoparticle (NP) decorated TiO2 nanowire (NW)/reduced graphene oxide (RGO) thin-film (TF) heterostructure as a UV detector, using a controlled method called the glancing angle deposition technique. Transmission electron microscope images show Ag NPs (size 7–13 nm) covering the entire surface of the TiO2 NWs. A high absorption as well as photoluminescence for the Ag NP-TiO2 NW/RGO TF sample reveals the generation of a large number of electron–hole pairs compared to bare TiO2 NW. The resulting plasmonic UV photodetector from the Ag NP-TiO2 NW/RGO TF exhibits a rectification ratio of 5039 (+10 V) and responsivity of 1760 A W−1 at 350 nm light (with power density as low as 0.58 µW cm−2). Moreover, the device shows fast response speed (rise time of 157 ms and fall time of 488 ms) with detectivity and noise equivalent power of 6.659 × 1013 Jones and 51 fW, respectively. The enhanced plasmonic field and high scattering of light, along with the high mobility RGO layer at the bottom, result in the superior performance of the device.

Recent Advances in Plasmonic Photocatalysis Based on TiO2 and Noble Metal Nanoparticles for Energy Conversion, Environmental Remediation, and Organic Synthesis

“…The scattering of the light photons and their reabsorption by the neighboring semiconductor increases the probability of light utilization, potentially increasing the light-harvesting properties. [50,51] Finally, photothermal heating following plasmon decay can also contribute to photocatalytic activities by increasing the local temperature close to the surface (catalytic sites). [52,53]…”

A novel high performance photodetection based on axial NiO/β-Ga2O3 p-n junction heterostructure nanowires array

“…Moreover, vertical NWs array has the ability to trap more incident photons and may enhance the photon absorption [35]. Moreover, from the XRD (figure 4) it is observed that the crystallite size is decreased in case of the axial NiO/β-Ga 2 O 3 HS NW sample for which generation of more electron-hole pairs are being observed [36]. Using the Tauc's equation ( ( ) )…”

In Situ Deposition of Reduced Graphene Oxide on Ti Foil by a Facile, Microwave-Assisted Hydrothermal Method

“…Figure 5b,d,f present a Log (I)-V between the forward and reverse biases of the composite structures. The rectifying nature of the TiO 2 /rGO heterojunction and an increase in the asymmetry between the forward and reverse biases is highlighted more for the Ti-TiO 2 -rGO-1h structure, as presented in Figure 5b; for the Ti-TiO 2 -rGO-2h and Ti-TiO 2 -rGO-3h structures, a slight rectification behavior appeared (Figure 5d,f) [37]. In order to evaluate the characteristics of the TiO 2 /rGO junction, the thermionic emission relation from the current-voltage was used [38].…”