Regulation and characterisation of the expansion structure of dickite layers

A dickite with an expanded layer structure was prepared by the co-calcination of the dickite-urea intercalation complex, urea, and potassium chlorate at 450°C. The expansion degree of the dickite layer could be regulated by the mass ratio (P/I) of potassium chlorate to the intercalation complex. XRD and SEM results showed that with the increase of the P/I ratio, the (002) diffraction intensity of expanded dickite gradually weakened and the degree of layer expansion gradually increased. When the P/I ratio exceeded 0.375, the expanded dickite exhibited an accordion-like porous morphology. The layer expansion of dickite exposed more internal layer surfaces, which was conducive to increasing the specific surface area, mesopore volume, and absolute ζ-potential, thus enhancing the adsorption capacity of methylene blue.