Visible light induced CO2 reduction and Rh B decolorization over electrostatic-assembled AgBr/palygorskite

AgBr/palygorskite composite was prepared by an in situ electrostatic adsorption–deposition–precipitation method and characterized by field emission scanning electron microscope (FE-SEM), X-ray diffraction (XRD), UV–Vis diffuse reflection, and BET surface measurements techniques. The layer negative charge and larger specific surface area of palygorskite, along with the poor cation-exchange ability of tetra-n-butyl ammonium cation (N(CH2CH2CH2CH3)4+) due to its larger ion radius, could mainly account for high dispersity of AgBr on the surface of fibrous palygorskite. The rate of Rh B decolorization and CO2 reduction with H2 as a proton donor and reductant over AgBr/palygorskite was about three and two times faster than that of the corresponding bare AgBr, respectively. The strategy reported in this work can be easily extended to synthesize other palygorskite-based heterostructure catalysts.

Graphical abstractFigure optionsDownload full-size imageDownload high-quality image (53 K)Download as PowerPoint slideHighlights► AgBr particles were assembled electrostatically on fibrous palygorskite. ► Photomethanation of CO2 with H2 as proton donor and reductant was studied. ► Layer negative charges facilitate cationic Rh B dye adsorption. ► Large surface area mainly accounts for excellent activity of AgBr/palygorskite. ► Porous structure could enhance the stability of AgBr/palygorskite.