Self-powered narrowband visible-light photodetection enabled by organolead halide perovskite CH3NH3PbBr3/p-Si heterojunction

Abstract

In this work, we have reported self-powered narrowband visible-light photodetectors based on organolead halide perovskite CH3NH3PbBr3 (MAPbBr3)/p-Si heterojunctions, which were prepared by growing MAPbBr3 microcrystals on the p-Si substrate using a room-temperature antisolvent-assisted crystallization method. Morphological, structural, and optical investigations showed that the as-grown MAPbBr3 microcrystals possessed a high crystalline quality. Electrical characterizations showed that the hetero-pn junction was formed within the MAPbBr3/p-Si heterojunction. Thanks to the high crystalline quality of MAPbBr3 microcrystals, the as-fabricated heterojunction photodetectors operating under a bias voltage of 0 V exhibited a high on–off ratio of ∼5.3 × 105, a narrow photosensitivity spectrum with the full width at half maximum of 18.2 nm, a high photoresponse speed with the rising/falling time of 115.7/53.4 ms, and excellent stability to visible-light signals. Finally, the photodetection mechanism was proposed. It showed that the observed narrowband photodetection was attributed to the self-filtering effect caused by the thick MAPbBr3 microcrystals. The results presented in this work will provide valuable strategies for the fabrication of self-powered narrowband visible-light photodetectors in the future.

Ion Migration in the All-Inorganic Perovskite CsPbBr3 and Its Impacts on Photodetection

“…In recent years, the ion migration behaviors have further been evidenced both by experimental and theoretical investigations. − It was shown that halide species (Cl, Br, and I) have the lowest migration barrier height and diffuse with the assistance of grain boundaries and vacancy-type defects. ,, This results in an obvious energy band bending at both ends of the LHP film and subsequently produces the typical I – V hysteresis. For the LHP-based MSM-structured PDs, the effects of ion migration on the photodetection performance have rarely been concerned so far, although great efforts have been made previously, but they mainly focused on improving the photodetection performance of as-fabricated PDs and developing multifunctional (such as flexible, self-powered, and narrow/broad-band detection) devices. − In our opinion, the effects of ion migration should be considered in the LHP-based MSM-structured PDs because a bias voltage is necessarily applied, especially for weak light detection. It is worth noting that the ion migration has been observed in the mixed halide CsPbX 3 -based light-emitting diodes recently …”

Large ferro–pyro–phototronic effect in 0.5Ba(Zr0.2Ti0.8)O3–0.5(Ba0.7Ca0.3)TiO3 thin films integrated on silicon for photodetection

“…When compared with vertical multilayered BiFeO 3 /ZnTiO 3 thin‐film structures, our devices show 1.77 times higher responsivity and ~8300 times higher τ r and τ f 19 . Compared with other standard thin‐film PDs, such as Au/CH 3 NH 3 PbBr 3 /p‐Si/Si, our devices show 4280 and 35,600 times faster τ r and τ f , respectively 20 …”

“…As described in our previous work, a 3 nm SiO x native oxide layer exists at the n-Si/ BCZT interface. 21 The BCZT layer was grown following the same procedure as that reported in our previous work 20,22 and by using a BCZT target prepared by a conventional solid-state reaction as previously described by Oliveira et al 23 The vacuum chamber was first evacuated down to a low pressure of 1 × 10 −6 mbar before the deposition. During the deposition, the substrate was maintained at a temperature of 330°C and at a distance of 87.3 mm from the target.…”

“…19 Compared with other standard thin-film PDs, such as Au/CH 3 NH 3 PbBr 3 /p-Si/Si, our devices show 4280 and 35,600 times faster τ r and τ f , respectively. 20 Herein, we demonstrate the performance of a Al/Si/ SiO x /BCZT/ITO device structure, relating it to the structural and ferroelectric properties that give rise to a combined ferro-pyro-phototronic mechanism.…”

Low Detection Limit Circularly Polarized Light Detection Realized by Constructing Chiral Perovskite/Si Heterostructures

“…On the one hand, the built-in electric field of the heterostructure provides the driving force to effectively separate and transport the photogenerated carriers, leading to improved photodetection capability. [26][27][28][29][30][31][32] On the other hand, the depletion region generated at the interface of the heterostructure, resulting in the suppression of dark current, which is beneficial for detecting weak CPL signals. [33][34][35][36] Therefore, it would be a great opportunity for chiral perovskitebased heterostructure to achieve highly sensitive CPL detection with a low detection limit.…”