Self-powered ultraviolet/visible photodetector based on CuBi2O4/PbZr0.52Ti0.48O3 heterostructure

Abstract

Ferroelectric materials with significant remnant electric polarization have recently gained research focus for the fabrication of self-power photodetectors due to their photovoltaic effect. However, the photodetectors based on ferroelectric materials display poor performance owing to their weak photovoltaic effect of the ferroelectric depolarization field (Ed) on photo-generated charge carrier separation. In this work, we fabricate self-powered photodetectors based on CuBi2O4/PZT heterostructure. The heterojunction reveals a photoresponsivity of 0.24 mA/W and a detectivity of 2.40 × 1010 Jones under 0 V bias with a maximum 7.51 μW/cm2 illumination intensity at 425 nm, which is substantially improved compared to PZT-only device. The observed rise and fall time of the composite CuBi2O4/PZT thin film is around 24 and 46 ms, respectively, which is faster than that of PZT photodetector (67 and 106 ms). Moreover, the photocurrent CuBi2O4/PZT of device is observed to be 12.7 × 10−10 A in the downpoling state and 6.28 × 10−10 A in upward poling state, revealing that the direction of polarization field can modulate the photocurrent. This work provides a promising strategy for fabricating ferroelectric heterojunction photodetectors with enhanced performance.