Eco-friendly synthesis of Zn0.97La0.03O compound with natural polysaccharide and its application in methylene blue and eosin dyes discoloration

Abstract

Herein, a study about to eco-friendly synthesis of Zn0.97La0.03O compound using Mangifera Indica gum and its application in the methylene blue and eosin dyes discoloration was conducted. The compound presented lattice and surface defects that enhanced the photocatalytic activity. Defect concentrations were determined by area percentages under Gaussian curves fitted from the Photoluminescence spectrum. The concentrations were V0 = 39.63 %, V0+ = 11.82 %, and VZn = 48.55 %. Furthermore, the compound exhibited a significant surface area measuring 12.2 m2 g−1 and an average particle size of 34 nm. The photocatalytic test showed that the Zn0.97La0.03O compound had a discoloration rate of 100 % for methylene blue and 77.8 % for yellow eosin. The scavenger tests confirmed that holes and hydroxyl radicals were the crucial species in the decolorization mechanisms. Finally, after three cycles, the material effectively removed methylene blue (100 %), but only removed 48.1 % of eosin in the third cycle.