Mechanism insight into the enhanced photocatalytic purification of antibiotic through encapsulated architectures coupling of crystalline Cu2O/amorphous TiFe layer double hydroxide

Abstract

Amorphous materials are one of the important candidates for improving heterogeneous photocatalysts because of their unique electronic structures and abundant catalytic sites originating from disorder atomic arrangements. However, there is still much room for the development of new crystalline/amorphous heterogeneous composites for photocatalytic application. Hence efficient synthetic strategies for preparing new crystalline/amorphous heterojunctions are highly desired. Herein, we have realized the deep optimization of photocatalytic activity by fabricating crystalline/amorphous Cu2O/Ti-Fe layer double hydroxide (LDH) heterojunctions. Thanks to the typical Z-scheme mechanism originating from the crystalline/amorphous interfaces, the photocharge separation and catalytic active sites obviously enhance compared to single Cu2O and LDH counterparts. As expected, the photocatalytic removal of tetracycline (TC) of the as-prepared Cu2O/Ti-Fe LDH was over 5.2 and 2.2 times those of the pristine Cu2O nanospheres and Ti-Fe LDH nanosheets. This work illustrates the origin of crystalline Cu2O nanospheres encapsulated in amorphous Ti-Fe layer double hydroxide nanosheets for enhanced photocatalytic activity driven by visible light, and provide a general Cu2O-templated solution-phase synthetic method for the synthesis of novel double-metal layer double hydroxide amorphous nanostructures.