Visible light sensitized porous clay heterostructure photocatalyst of zinc-silica modified montmorillonite by using tris(2,2′-bipyridyl) dichlororuthenium

Abstract

A visible-light sensitization on porous clay heterostructure of zinc-silica modified montmorillonite (PCH-ZnSi) photocatalyst with tris(2,2′-bipyridyl) dichlororuthenium has been conducted. The preparation of PCH-ZnSi was performed by intercalation of surfactant and co-surfactant of cetyl trimethyl ammonium bromide-trimethanol amine followed by approaching zinc oxide and silica precursor under microwave assisted method followed by calcination, meanwhile the ruthenium complex attachment was conducted by Ru(Bpy)32+ impregnation into PCH-ZnSi. The results showed that porous clay heterostructure was successfully obtained as shown by the increased d001 of clay structure identified from XRD measurement and TEM analysis which represented the layers space ranging at 1.9-2.9 nm from 1.09 nm of montmorillonite. This increasing is in line with the evolution of pore distribution and the specific surface area enhancement. Moreover the sensitized form (Ru(Bpy)32+/PCH-ZnSi) represented the increasing photocatalytic activity in both UV and visible light exposure which corresponding to the photoluminescence spectrum ranging at visible region. The physicochemical characteristics supported the photocatalytic activity as revealed by the high degradation efficiency of methylene blue photodegradation which reached 99.8% under UV and 87.6% under visible light. The material has stability as it has maintained efficiency until 6 cycles, correlated with the availability of photoactive sites identified by XPS analysis.