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In this work, we report the design and fabrication of self-powered binary response PDs based on II-type heterostructures consisting of SnS x nanoflakes (NFs) and rutile TiO 2 nanorod arrays (NRs). The TiO 2 NRs effectively block light with wavelengths below 400 nm from reaching SnS x . Under 385 nm light, the photoelectrons in TiO 2 recombine with holes in SnS x at the interface due to the energy band bending, resulting in a positive photocurrent. Under 410 nm light, the photoelectrons in SnS x and the photogenerated holes in TiO 2 accumulate at the interface, overcoming the interfacial potential barriers induced by the higher Fermi levels of SnS x and inducing a negative photocurrent. Based on the bipolar response, the dual-band imaging capability without external filters and the light-encrypted OR, AND, and NOT logic gates using a single device are demonstrated. This work provides a blueprint for the development of multifunctional self-powered PDs that can simplify system architecture, reduce the energy consumption, and improve accuracy for applications, such as visual systems, light-controlled logic circuits, and encrypted optical communications., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier Inc.)