Tailoring the interface assembly of mesoporous TiO2 on BTO film toward high-performance UV photodetectors

Abstract

TiO₂-based nanomaterials are considered the most promising photoelectric materials for the construction of high-performance ultraviolet photodetectors. Nevertheless, they have always suffered from poor interface crystallinity that restricts the generation of photogenerated carriers and limits the enhancement of properties. Herein, a high-performance mesoporous titanium dioxide based ultraviolet photodetector fabricated on a self-polarized BaTiO₃ film (denoted as BTO@mTO) was introduced by an interface assembly strategy and spin-coating, through an in-situ annealing process. Due to the self-polarization of the ferroelectric phase BaTiO₃ and highly crystalline interface layer, the efficient separation of carriers is facilitated. Hence, the responsivity of BTO@mTO PD is up to 8.53 × 10⁻³ A W⁻¹ under 310 nm. Compared with pure mTO PD, the I_ph/I_d ratio of BTO@mTO PD increased 17 times to 680.