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High‐performance broadband photodetectors (PDs) are essential components in spectroscopy, remote sensing, imaging, and light communication applications. In this paper, Sb2Se3 nanoparticles (NPs) are uniformly deposited on TiO2 nanorod arrays (NRs) to construct a type II heterojunction with good interfacial contact by a simple two‐step potentiostatic electrochemical deposition method combined with N2 atmosphere annealing at 280, 290 and 300 °C to control the amount of Se in Sb2Se3. A good interfacial contact between Sb2Se3 and TiO2 is conducive to the separation and transport of photogenerated carriers. Sb2Se3/TiO2 PDs exhibit excellent self‐powered photoresponse in a broad spectral range from ultraviolet‐visible‐near infrared (UV‐VIS‐NIR) due to the combined effects of high light absorption, low defect density, and more suitable band alignment. The optimal parameters with a responsivity of 13.48 A W−1, detectivity of 7.9 × 1011 Jones, and response time of 18/20 µs are demonstrated for the PDs annealed at 290 °C. The excellent performance broadband Sb2Se3/TiO2 PDs are used to construct the application models in the light communication for light encryption and flaw detection. This work opens up a new strategy for Sb2Se3/TiO2 PDs in multifunctional applications. [ABSTRACT FROM AUTHOR]

In this paper, SrTiO3 (STO) nanocrystals (NCs) are produced on the TiO2 surface through a second hydrothermal conversion reaction to construct STO/TiO2 core–shell nanorod arrays (NRs) and the amount of STO NCs is controlled by adjusting the conversion time. Here, the self-powered photoresponse properties are demonstrated in STO/TiO2 heterojunction devices. The synergism of the ferroelectric polarization effect of the STO layer and the interface effect of STO/TiO2 heterojunctions on the performance of PDs is investigated. The direction of the ferroelectric depolarization field in the STO layer controlled by an external polarization bias can regulate the magnitude of PD photocurrent, resulting in the enhancement or reduction of the self-powered photocurrent in STO/TiO2 heterojunction PDs without applying bias. The PDs exhibit a self-powered photodetection ability with light irradiance-adaptability and simulate the photopic and scotopic adaptation behavior of eyes. The results suggest a new perspective of using ferroelectric material-based PDs to realize visual servoing in a wide intensity range of light irradiance for machine vision sensors that perceive different lighting environments. [ABSTRACT FROM AUTHOR]