Interfacial Electronic Regulation of GO/Na0.5Bi2.5Nb2O9 Aurivillius-Layered Perovskite Heterointerfaces for Enhanced Photocatalysis

Constructing heterointerfaces between semiconductor photocatalysts and carbonaceous materials is an effective strategy for enhancing photocatalytic performance. However, the role of graphene oxide (GO) in modulating the interfacial electronic properties of Aurivillius-layered perovskites has remained unexplored, until now. In this work, GO/Na0.5Bi2.5Nb2O9 (ABNO) composites, denoted as GABNO, with different GO loadings were successfully synthesized using a hydrothermal method. Structural, chemical and surface characterizations confirmed the formation of intimate GO/ABNO heterointerfaces without altering the crystal structure of ABNO. GO incorporation established electronically coupled heterointerfaces and modified the interfacial electronic environment, as evidenced by XPS and flat-band potential analyses. Among all samples, GABNO 0.1 (0.1 mg GO loading) exhibited the highest photocatalytic activity, achieving nearly 100% Rhodamine B removal within 120 min and significantly enhancing methyl orange removal under UV–visible light irradiation. Radical trapping experiments further revealed that GO altered the dominant photocatalytic reaction pathway from hole-dominated oxidation to superoxide-radical-mediated degradation. The superior photocatalytic performance is attributed to GO-induced interfacial electronic interactions, which facilitate efficient interfacial electron utilization and alter the dominant photocatalytic reaction pathway. This work provides new insight into the design of GO/Aurivillius-layered perovskite and highlights interfacial electronic regulation as an effective strategy for developing high-performance photocatalysts for environmental remediation.