Attapulgite-interpenetrated g-C3N4/Bi2WO6 quantum-dots Z-scheme heterojunction for 2-mercaptobenzothiazole degradation with mechanism insight

g-C 3 N 4 and Bi 2 WO 6 quantum dots (BWQ) are well integrated with interpenetrated attapulgite nanorods by a simple yet effective in situ growth method. An interfacial internal electric field (IEF) is formed at equilibrium between g-C 3 N 4 and BWQ, which endows the resulting BWQ/g-C 3 N 4 /ATP (BCA5) nearly-100% photocatalytic degradation activity of 2-mercaptobenzothiazole in water under visible-light. • A novel Bi 2 WO 6 QDs/g-C 3 N 4 /ATP nanocomposite is synthesized by an in situ growth method. • The nanorod-structured ATP acts as scaffolds and bridges to expand inner space of g-C 3 N 4 . • An interfacial IEF is formed at equilibrium between g-C 3 N 4 and Bi 2 WO 6 QDs. • The IEF-driven Z-scheme mechanism is in favor of the separation and transport of charge carriers. • The Bi 2 WO 6 QDs/g-C 3 N 4 /ATP exhibits nearly-100% photocatalytic activities for MBT degradation. The rational utilization of graphitic carbon nitride (g-C 3 N 4 ) and quantum dots (QDs) semiconductors to highlight their merits as efficient photocatalysts remains attractive and challenging. Targeted integration of g-C 3 N 4 and QDs with expanded interfacial contact and multi-channel electron transfer is an effective means to boost the transfer efficiency of photogenerated electrons and achieve prominent photocatalytic activity. In this article, novel attapulgite (ATP)-interpenetrated Bi 2 WO 6 QDs/g-C 3 N 4 nanocomposites (BWQ/g-C 3 N 4 /ATP, designated as BCAs) are successfully fabricated through a simple and effective in situ hydrothermal growth method. The nanorod-structured ATP acts as numerous bridges to intercalate into the interlayers and expands inner space of g-C 3 N 4 . Theoretical calculation results indicate that an interfacial internal electric field (IEF) is formed where electrons transfer from g-C 3 N 4 to Bi 2 WO 6 . Originating from the intact interfacial contact of the expanded g-C 3 N 4 and highly dispersed BWQ with reinforcing electronic transferability of ATP, the optimal sample of BCA5 with higher specific surface area, more active sites and electron transfer channels, and stronger light harvestability, exhibits a nearly-100% degradation of organic contaminant of 2-Mercaptobenzothiazole in water, 35-, 17- and 3-fold rate constant higher than that the pristine g-C 3 N 4 , BWQ and Bi 2 WO 6 /g-C 3 N 4 counterparts, respectively. Various characterization techniques are employed to put forward the mechanisms in depth on MBT degradation route and IEF-induced photocatalytic Z-scheme over the BCA5 under photoexcitation.