Phosphate or arsenate modified UiO-66-NO₂ : Amorphous mesoporous matrix

The metal-organic framework UiO-66-NO₂ was synthesized and was converted to amorphous mesoporous matrix by arsenate and phosphate modification. The 10 mM phosphate or arsenate solutions immersed for 120 min replaced 20% of zirconium cluster with partial deterioration of the crystalline structures at reduced surface areas and pore sizes which had lowered zeta potentials. The 50 mM arsenate or phosphate modification led to nearly complete replacement of zirconium clusters with total conversion into amorphous mesoporous matrix with low surface areas and enlarged internal pores, and further reduced surface zeta potentials in waters. The yielded matrix was tested on the adsorption capacity of lead ions from neutral waters.