Perovskite-based composite materials for broadband NIR detection

The intrinsic optical bandgap of perovskite materials limits their efficient capture of near-infrared (NIR) photons. Moreover, the introduction of Sn²⁺ ions to achieve a narrow bandgap introduces susceptibility to oxidation, severely compromising material stability and device performance. From the perspective of materials engineering, this paper systematically reviews three major strategies to address these challenges in constructing high-performance NIR photodetectors. Firstly, through materials design approaches such as Sn/Pb mixed perovskites, dimensionality engineering, and precise defect passivation, the bandgap is effectively narrowed to ~1.2 eV while simultaneously enhancing the oxidation resistance and crystal quality of tin-based perovskites. Secondly, the principles of materials pairing for achieving spectral extension and optimizing carrier dynamics via heterostructure construction are discussed, with a focus on band alignment and interfacial charge transfer mechanisms in combinations of perovskites with organic/inorganic materials, traditional semiconductors such as silicon and germanium, and low-dimensional materials like graphene. Composite materials formed by leveraging the tunable size of quantum dots with perovskites are utilized to enhance NIR performance through interfacial synergistic passivation and carrier multiplication effects. Furthermore, the introduction of upconversion materials enables indirect NIR detection through photon energy conversion. Finally, the future development prospects for NIR detection based on perovskite-based composite materials are presented.