Photochromism-promoted highly efficient photocatalytic degradation in ferroelectric photochromics

Abstract

Ferroelectric materials are increasingly being recognized as potential candidates for multi-field coupling catalysis (photo and pyro-/piezo catalysis) due to their intrinsic polarization behavior. However, ineffective separation of photogenerated carriers is still the main factor limiting their photocatalytic performance. Here, we report reversible photochromic bismuth layered ferroelectrics (Na_0.5Bi_4.5Ti₄O₁₅ (NBT) and Bi₄Ti₃O₁₂ (BT)) with significantly enhanced catalytic degradation. It has been found that the photochromic reaction plays an important role in modulating the photocatalytic or piezocatalytic properties. The photocatalytic degradation rates of NBT and BT samples after visible light irradiation were 2.6 and 1.6 times those before irradiation, and the piezocatalytic degradation rates were 1.6 and 1.6 times those before irradiation, respectively. This work provides a feasible strategy to realize highly efficient photo/piezocatalytic behavior by controlling photochromic reactions.