Blueshift Enhanced\nGiant Lateral Photovoltaic Effect\nObserved in MoS<sub>2</sub> Granular Film (Quantum Dots)/Porous Silicon/p-Si

The lateral photovoltaic effect (LPE) has garnered significant\nattention due to its extensive applications in fields such as position-sensitive\ndetectors, artificial intelligence, imaging, automatic driving, and\nso on. Enhancing LPE sensitivity has long been a focal point for researchers,\nwith recent years showing advancements but still leaving room for\nimprovement. In this study, we achieved sensitivities of up to 1195.02\nmV/mm for MoS<sub>2</sub> granular film (MoS<sub>2</sub>-GF)/porous\nsilicon (PS)/p-Si and 951.71 mV/mm for MoS<sub>2</sub>-QDs/PS/p-Si\nstructures under 520 nm laser irradiation. The results demonstrate\nsensitivities 1 to 3 orders of magnitude higher than those of traditional\nLPE devices and surpass the majority of previously reported position-sensitive\ndetectors. Leveraging the enhanced light absorption in PS, we observed\na blueshift due to multiple excitonic transitions induced by the quantum\nconfinement effects of MoS<sub>2</sub> granular films and quantum\ndots, assisting the light response of LPE. By forming heterojunctions\nand serving as carrier mediators, they effectively suppress carrier\nrecombination of photogenerated carriers and holes on the PS surface,\nthereby enhancing utilization efficiency. Furthermore, they extend\nthe short carrier migration length caused by the irregular surface\nof PS, promoting lateral diffusion of photogenerated carriers and\ngenerating significant lateral concentration gradients. The advancements\npresent novel pathways for ultrawideband and ultrasensitive optoelectronic\nand position-sensitive detectors, underscoring their vast potential\nin diverse optoelectronic applications.