fig4

Figure 4. PV performance between pure PTO and PTO(Ni) film. J-V curve of pure PTO and PTO(Ni) film under the irradiation of 600 mW/cm²I_light from (A) 405 nm and (B) 375 nm laser; (C) Short-circuit current density (J_SC) of pure PTO and PTO(Ni) film at various light intensities. The inset depicts the excellent response of PTO(Ni) film at low light intensities (0.3-4.22 mW/cm²); (D) Photoresponsivity (R) of PTO(Ni) film (this work) compared with previously reported perovskites under blue light. The pink hexagons, purple circles, blue diamonds, and green squares represent epitaxial films, ceramics, single crystals, and heterostructure, respectively. PV: photovoltaic; PTO: PbTiO₃.