Mo-Induced Interfacial Charge Modulation in NiO/In ₂ O ₃ Vertical p-n Junction Heterostructure for Self-Powered Broadband Photodetector

The advancement of optoelectronic devices and multifunctional systems requires the development of high-performance, energy-efficient broadband photodetectors that operate without an external bias. In this context, the present work demonstrates the photodetector performance of a vertically stacked thin film of Mo-decorated p:NiO/n:In 2 O 3 (Mo/NIN), where the incorporation of Mo modulates interfacial charge within the NiO/In 2 O 3 heterostructure. The microstructural analysis reveals a nanorod morphology in the Mo/NIN thin film, with Mo-nanosheet incorporation inducing surface modification that enhances photodetector performance by improving light absorption and charge transport at the metal-semiconductor interface. The Mo/NIN-based photodetector exhibits a pronounced photocurrent of 9.82 nA and a notable detectivity of 4.79 × 10 10 Jones upon 1000 nm illumination, along with a rapid response time of 100 ms even at zero bias, indicating efficient charge separation and transportation with reduced recombination at the NiO/In 2 O 3 interface, along with the localized surface plasmon resonance effect induced through Mo incorporation. Overall, the promising figures of merit of the Ag:Mo/NIN:Ag photodetector device at very low-light intensity (26.3 μW/cm 2 ) in self-powered mode pave the way for scalable, energy-efficient broadband sensing.