Manipulation of ferroelectric polarization and light absorption in non-noble metal/Aurivillius ferroelectric hybrid to enhance self-driven photodetection by coupling ferro-pyro-phototronic and plasmonic effect

Abstract

Aurivillius ferroelectrics materials with layer perovskite structure, spontaneous polarization and ferro-pyro-phototronic effect afford a promising avenue for self-powered photodetectors. Nevertheless, poor photo-response caused by weak remanent polarization and low absorption coefficient hinders their further application. Herein, we demonstrate an excellent self-powered photodetector in nanosheets-assembled Bi microspheres array/Nd-doped Bi4Ti3O12 [Bi3.8Nd0.2Ti3O12] nanofibers heterostructured, which can rationally couple between ferroelectric polarization and ferro-pyro-phototronic effect in Aurivillius ferroelectric Bi3.8Nd0.2Ti3O12 and plasmonic effect in non-noble metal Bi. Firstly, an A-site doping with lanthanoid cation Nd3+ and dimension lowering strategy is proposed to improve the ferroelectric properties by reducing the oxygen vacancy concentration and coercive force field of Bi4Ti3O12 nanofibers through electrospinning method. Furthermore, the Bi nanosheets-assembled microspheres array allowing multiple reflection and scattering of incident light is introduced to enhance the local electromagnetic field and light absorption of Bi3.8Nd0.2Ti3O12. Ultimately, the Bi@Bi3.8Nd0.2Ti3O12 with negatively polarized obtains a superior zero-bias photocurrent of -500 nA under 390 nm laser illumination, which is 195.31 and 22.16 times higher than unpolarized Bi4Ti3O12 and Bi3.8Nd0.2Ti3O12, respectively. Simultaneously, an outstanding detectivity (8.11 ×1011 Jones) and fast photoresponse time (57/114 µs) are correspondingly achieved. Our research provides a reliable way to simultaneously realize large ferroelectric polarization and high light absorption for jointly manipulation of electrons and photons in self-powered optoelectronic devices.