Hybrid Device Architecture Using Plasmonic Nanoparticles, Graphene Quantum Dots, and Titanium Dioxide for UV Photodetectors

Abstract

In this work, a nanoscale device architecture is demonstrated for a UV photodetector application on sapphire (0001), incorporating the plasmonic hybrid nanoparticles (HNPs), graphene quantum dots (GQDs), and titanium oxide (TiO2) for the first time. The hybrid GQDs/TiO2/HNPs photodetector exhibits the photocurrent of 1.58 × 10–5 A under the 1.64 mW/mm2 of 275 nm illumination at 10 V, which is around two order increase from the bare TiO2 device. The proposed architecture demonstrates a low dark current of ∼1 × 10–10 A at 10 V and thus the device demonstrates an excellent photo to dark current ratio along with the improved rise and fall time on the order of several hundred millisecond. The enhanced performance of device architecture is attributed to the efficient utilization of localized surface plasmon resonance (LSPR) induced hot carriers as well as scattered photons from the plasmonic HNPs that are fully encapsulated by the photoactive TiO2 layers. Furthermore, the addition of GQDs on the TiO2 can offer an additional photon absorption pathway. The proposed hybrid architecture of GQDs/TiO2/HNPs demonstrates the integration of the photon absorption and carrier transfer properties of plasmonic HNPs, GQDs, and TiO2 for an enhanced ultraviolet (UV) photoresponse. The photocurrent enhancement mechanisms of the hybrid device architecture are thoroughly investigated based on the finite-difference time domain (FDTD) simulation along with the energy band analysis. This work demonstrates a great potential of the hybrid device architecture for high-performance UV photodetectors.

Enhanced Performance of WO3 Photodetectors Through Hybrid Graphene-Layer Integration

“…The comparison of the essential photodetector device parameters such as photocurrent and responsivity with those of our work and past reports is listed in Table . The present study confirmed that the introduction of the GR layer into the WO 3 device exhibited superior photocurrent values to the various single layers, bilayers, and multilayers of photodetectors even at lower power densities and applied bias voltages. ,,,,− Enhancement of the photodetector device performance is due to the addition of GR onto the WO 3 layer. Finally, the WO 3 /GR device exhibits superior photodetector characteristics, and it is tuned to detect both UV and visible radiations even at the lower power densities.…”

“…Various materials such as MoS 2 , NiO/Ga 2 O 3 , WO 3 , Nb 2 O 5 , WS 2 /TiO 2 , K 2 Nb 8 O 21 , TiO 2 /WO 3 , and graphene (GR) were used as photoactive layers in photodetector devices. − Most recently, some of the hybrid nanostructured materials such as WO 3 nanowires, Bi 2 Se 3 nanobelts, CuInS 2 /ZnS core–shell quantum dots (GQDs), and GR GQDs/TiO 2 /hybrid nanoparticles (HNPs) are explored toward photodetector applications. − Among them, GR was found to be more captivating for optoelectronic and sensor applications. GR was used in ultrafast lasers, solar cells, light-emitting devices to touch screens, transparent electrodes, field-effect transistors, supercapacitors, actuators, organic photovoltaics, etc. , Principally, GR was a single layer of carbon atoms arranged in a honeycomb or hexagonal lattice structure, and it is a gapless semiconductor .…”

High-Efficacy Hierarchical Dy2O3/TiO2 Nanoflower toward Wastewater Reclamation: A Combined Photoelectrochemical and Photocatalytic Strategy

“…19 − 21 Several strategies have been studied to enhance the photocatalytic efficiency of visible-light photocatalysts, in particular, doping, band gap regulation, structural control, surface sensitization, and phase transfer. 22 − 24 Characteristic features of efficient photocatalysts include photoactivity to biological and chemical matters, nontoxicity, ability to absorb near UV–visible regions, photostability, and cost-effectiveness.…”

Organic Photodetectors with Extended Spectral Response Range Assisted by Plasmonic Hot-Electron Injection

“…Notably, plasmonic nanostructures which can yield near-unity absorption at the resonant wavelengths have been successfully introduced into photodetectors made of inorganic semiconductors, e.g., silicon [ 23 , 24 , 25 ], titanium dioxide [ 26 , 27 ], and zinc oxide [ 28 , 29 , 30 ], for extending their operating spectral ranges. In those photoelectric devices, light absorption occurs in metals by the excitation of plasmonic resonances, followed by the generation of free carriers in neighboring semiconductors, based on the processes of hot-carrier transfer, charge-transfer transition, or resonant energy transfer [ 31 , 32 , 33 ].…”