Plasmonics StimulatedEnhanced Performance MoS₂/WO₃ HeterojunctionBased Broadband Self-PoweredPhotodetector

Abstract

The demand for broadband photodetectors that span the UV, visible, and NIR spectrum is ever-increasing due to their critical role in numerous applications. This research explores the incorporation of gold nanoparticles (Au-NPs) to harness localized surface plasmon resonance (LSPR) effects in the development of high-performance photodetectors. Our study introduces a unique MoS₂/WO₃ heterojunction, previously unexplored. This novel approach extends the photodetection range from UV to NIR, bridging the inherent spectral limits of tungsten trioxide (WO₃) in the UV to visible and molybdenum disulfide (MoS₂) in the visible to NIR regions. Notably, the heterojunction demonstrates self-biasing characteristics. Furthermore, the incorporation of gold nanoparticles enhances performance, yielding a incredible ∼200% enhancement in responsivity. Upon optical illumination of 455 nm at 2 V applied bias and 10 μW optical power, MoS₂/WO₃ and Au-MoS₂/WO₃ photodetectors exhibited high responsivity of 370 and 720 mAW^–1, respectively. The Au-MoS₂/WO₃ device displayed remarkable external quantum efficiency of 226% and noise equivalent power as 5.49 × 10^–10 WHz^–1/2. The Au-MoS₂/WO₃ device demonstrates improved rise and fall times, measuring around 55 and 48 ms, respectively. These values represent a notable enhancement of 20.49% and 30.10% for the rise and fall times compared to the MoS₂/WO₃ device. The study comprehensively characterizes their structural, electrical, and optical attributes and assesses their photodetection performance across the UV, visible, and NIR regions. Our findings highlight the potential of these devices to revolutionize photodetection technologies and catalyze innovation in diverse applications.