In situ, seed-free formation of a Ruddlesden–Popper perovskite Cs₂PbI₂Cl₂ nanowires/PbI₂ heterojunction for a high-responsivity, self-powered photodetector

The Cs2PbI2Cl2 nanowires/PbI2 heterojunction enlarged the built-in field (Eb), which led to the suppressed carrier recombination and enhanced carrier transportation. The resulting device reached a specific detectivity (D*) maximum of 3.02 × 1012 Jones.