Precisely Tailoring\nFerroelectric Photocurrent via\nMagnetic Spin Chain toward Efficient Self-Powered UV Photodetectors

The study of Aurivillius multiferroic films has become\nincreasingly\nprevalent in the contents of solar energy and light-sensitive detectors.\nIn principle, the characters of photocarrier separation driven by\nferroelectric polarization can be candidates for self-powered photodetectors.\nIn this work, magnetic Fe doping is proposed for constructing Fe–O–Fe\nspin chain structures, which not only serve as a scaffold for electron\ntransport but also combine ferroelectric polarization and magnetic\nexchange in Bi<sub>4</sub>Ti<sub>3–<i>x</i></sub>Fe<sub><i>x</i></sub>O<sub>12</sub> (<i>x</i> = 0, 0.5, 0.7, 0.8, 0.9, and 1.0) multiferroic UV photodetector.\nUsing this approach, the precise control of the photocurrent and the\nperformance improvement of the photoelectric readout are then realized,\nwith a noise equivalent power of 9.8 × 10<sup>–14</sup> W and detectivity <i>D</i>* ∼ 7.2 × 10<sup>12</sup> Jones. Furthermore, the outstanding energy conversion of\n∼3.7% under AM 1.5 G irradiation is significant for future\npractical self-powered detection.