Fabrication and characterization of novel lignocellulosic biomass tailored Fe3O4 nanocomposites: influence of annealing temperature and chlorazol black E sequestration

Abstract

This study discusses the prospect of using a waste biomass material in the development of novel technological materials for sustainable environmental applications. Novel iron oxide nanocomposites (IONCs) were fabricated using a waste lignocellulosic biomass (LB) material (papaya leaves) by employing the chemical precipitation technique. The IONCs were subjected to annealing temperatures of 353, 573, and 773 K, and precursor ratios of 1 : 1 and 2 : 1. The nanocomposites were characterized by FTIR, XRD, TEM, SAED, EDX, CHN(O), N₂ adsorption, and VSM analyses. An increase in annealing temperature of the LB–IONCs resulted in larger particle size, better crystallinity, and improved magnetic properties. LB–IONCs annealed at 773 K were found to be the most effective material (among its counterparts) for the removal of chlorazol black E, with an efficiency of 96.45% and a monolayer sequestration capacity of 40.02 mg g⁻¹. Hydrogen bonding and π–π dispersive interactions governed the sequestration mechanism.