One-pot vanadium-based organic frameworks for DEHP effective removal: Relationships between the synthetic strategy, characterization, adsorption and solar-driven photocatalytic activity

Abstract

Metal-organic frameworks (MOFs) are promising photocatalysts, yet the incorporation of vanadium into MOFs is prospective to achieve broad visible-light response, functionalized and topography-selective photocatalysts. Herein, we developed a series of self-assembly and template-free vanadium-based frameworks (V-MOFs) via a one-pot synthesis method accelerating the efficient adsorption and solar-driven photocatalytic degradation of DEHP, where V ions were immobilized by -COO groups to form various favorable configurations and the monodispersed transient V3+/V4+/V5+ centers served as active sites facilitating the separation of photogenerated charges. The advantageous photoelectron leaping capability, electron-hole lifetime and catalytic active sites of the synthesized V-MOFs were verified. The Mantel test analysis was applied to obtain the optimal synthetic route by exploring the correlation among the synthesis factors, V-MOFs’ characterization, and DEHP adsorption-degradation properties, the resultant V1-BDA@ and V1-H3BTB@ exhibited outstanding photocatalytic degradation and adsorption performances with a total DEHP (20 ppm) removal rate of 98 % in 240 min. The effective attack sites on DEHP were explained by Fukui function, and the photocatalytic degradation pathway of DEHP by V1-H3BTB@ was furtherly revealed.