Chain-to-Layer Dimensionality Engineering of Chiral Hybrid Perovskites to Realize Passive Highly Circular-Polarization-Sensitive Photodetection

Chiral hybrid perovskites (CHPs), aggregating chirality and favorable semiconducting properties in one, have taken a prominent position in direct circularly polarized light detection (CPL). However, passive high circular polarization sensitivity (g_res) photodetection in CHPs is still elusive and challenging. Benefitting from efficient control and turning of carrier transport of CHPs by dimensional engineering, here, we unprecedentedly proposed a chain-to-layer dimensionality engineering to realize high-g_res passive photodetection. Two novel 2D layered CHPs (R/S-PPA)­EAPbBr₄ (2R/2S) (PPA = 1-phenylpropylamine, EA = ethylammonium) are successfully synthesized by alloying an EA cation with small steric hindrance into the chained CHPs (R/S-PPA)­PbBr₃ (1R/1S). Particularly, compared with the neglectable photoresponse in 1R, the obtained 2R by chain-to-layer dimensionality engineering gives rise to an excellent photoconductivity and robust polar photovoltage effect (PPE) with a giant open-circuit voltage of 2.5 V. Furthermore, such PPE promotes realizing an impressive g_res in 2R up to 0.42 at zero bias because of the independent separation of photoexcited carriers, which is the highest value among the reported layered chiral perovskites. This work paves the way for the vigorous development of higher dimensional CHPs and will reveal their applications in the field of passive high-g_res CPL detection.