Polarization-enhanced photovoltaic response and mechanisms in Ni-doped (Bi0.93Gd0.07)FeO3 ceramics for self-powered photodetector

Multiferroic toxicity-free perovskite BiFeO3-based materials reveal potentials in photoelectrical conversion, energy harvesting and photodetector. This work highlights polarization-enhanced photovoltaic (PV) effects and mechanisms in B-site Ni-doped (Bi0.93Gd0.07)FeO3 ceramics with indium tin oxide (top electrode) and Au (bottom electrode) thin films. The enhanced PV effects are attributed to the reduced bandgap, polarization-modulated Schottky barrier, increased O 2p-Fe 3d orbital hybridization, and nucleation of domain walls to improve transportation of charge carriers. Improved PV parameters of responsivity (R) similar to 1.71 x 10(-2) A/W, detectivity (D*) similar to 9.56 x 10(11) Hz(1/2/)W (Jones), open-circuit voltage (V-oc) similar to 0.65 V, and short-circuit current density (J(sc)) similar to 80 mu A/cm(2) were obtained from the ITO/ (Bi0.93Gd0.07)(Fe0.97Ni0.03)O-3/ Au heterostructure after 2 kV/cm poling under 405 nm irradiation at 10(3) W/m(2) intensity. This work demonstrates that Ni-doped (Bi0.93Gd0.07)FeO3 ceramics can be potential candidates for self-powered UV photodetector.