Perovskite/GaAs-nanowire hybrid structure photodetectors with ultrafast multiband response enhancement by band engineering

We developed a hybrid structure photodetector combining one-dimensional(1D)inorganic GaAs nanowires and two-dimensional(2D)organic perovskite materials,which can achieve various performance enhancements using a relatively simple structure.Via the optical absorption enhancement of perovskite and the type-Ⅱ energy band structure formed by the heterostructure,the responsivity and detectivity of the photodetector from ultraviolet(UV)to visible(Vis)wavelengths are significantly enhanced,reaching 75 A/W and 1.49 × 1011 Jones,respectively.The response time of the photodetector was significantly decreased by 3 orders,from 785 ms to 0.5 ms,and the dark current was further reduced to 237 fA.A photodetector was prepared with enhanced responsivity and ultra-fast response time in the multiband region from the UV to Vis wavelength.To the best of our knowledge,this is the first time to combine inorganic Ⅲ-Ⅴ GaAs nanomaterials with organic perovskite materials,which verifies the effective combination of inorganic and organic materials in a mixed dimension.The excellent photoelectric per-formance of the perovskite/GaAs-nanowire hybrid structure photodetector makes it a potential candidate material for a wide range of photoelectric applications such as multiband photodetection.