Enhanced UV photosensing properties by field-induced polarization in ZnO-modified (Bi0.93Gd0.07)FeO3 ceramics

Self-powered photodetection was studied using x wt% ZnO-modified (Bi0.93Gd0.07)FeO3 (abbreviated as B7GFO-xZn) ferroelectric ceramics. The IT0/137GFO-xZn ceramic/Au photovoltaic (PV) cell was constructed for photosensing study at ultraviolet-A (lambda = 360 nm) and near-ultraviolet (lambda = 405 nm). The + 2kV/cm poled PV cell using B7GFO-1 wt%Zn ceramic under 360-nm irradiation displays maximal photocurrent density of similar to 364 mu A/cm(2) at 10(2) mW/cm(2) . Furthermore, a remarkable photosensing performance was observed with photoresponsivity (R) of similar to 3.02 x 10(-2) A/W, specific detectivity (D*) of similar to 2.27 x 10(12) Jones, and photoconductive gain (G) of similar to 10.4%. A sensitive photosensing response time (rise time, tau(r)) of similar to 9 ms was acquired under illumination from the 360-nm laser at 10(2) mW/cm(2). The enhanced photodetection performance originated from the collective influence of the narrower bandgap, enhanced p-n junction effect, E-fieldmodulated energy band tilt, and improved photocurrent generation due to the local conductive pathways formed by the interconnected domain walls and grain boundaries. This work provides an extensive analysis to elucidate the photovoltaic mechanisms in BiFeO3-based ceramics and explores their potential in selfpowered UV photosensing. (C) 2022 Elsevier B.V. All rights reserved.

Automated summary

Self-powered photodetection using ZnO-modified ferroelectric ceramics is studied. The results show that the ceramic exhibits high photocurrent density and responsivity under 360 nm laser irradiation, as well as fast response time. The improved performance is attributed to the narrower bandgap, enhanced p-n junction effect, E-field-modulated energy band tilt, and conductive pathways formed by domain walls and grain boundaries.