Broadband self-powered photodetection with p-NiO/n-Si heterojunctions enhanced with plasmonic Ag nanoparticles deposited with pulsed laser ablation

In this work, we report a comparative study of self-powered broadband photodetection properties of p-NiO/n-Si and p-NiO/silver nanoparticles (Ag-NPs)/n-Si heterojunction diode. The structural and optical properties of the proposed devices are studied using different microscopic and spectroscopic techniques. The current–voltage (I–V) measurements are performed on the devices to determine detectivity, responsivity, and time response under dark and illumination with AM1.5G simulated solar light and UV light. The findings from the I–V data show that the Ag-NPs mediated heterostructure has better self-powered broadband photoresponse compared to the p-NiO/n-Si heterostructure. In comparison to the p-NiO/n-Si heterojunction structure at zero bias, we achieved high responsivity (6.58 mA.W⁻¹), large detectivity (2.1 × 10¹⁰ cmHz^1/2/W), and fast response for Ag-NPs embedded p-NiO/n-Si heterostructure under AM1.5G solar simulated light. The enhancement in the self-powered broadband photodetection performance can be attributed to the localized surface plasmon-induced hot-electron generation in Ag-NPs. Further, the improvement in the photoresponse and hot carriers’ injection-transport mechanism is illustrated through the band diagram. Thus, the proposed device demonstrates the plasmonic effect of Ag-NPs in the self-powered broadband photodetection performance.