Performance-enhanced cellulose ternary composite in removing toxic lead ion pollutants: atom-level interfacial structures and pseudo-dynamic trapping process

It is appealing but challenging to modulate interfacial structures and reactivity of biomass composites at the atomic level, due to its importance in guiding experimental synthesis and developing application. In this work, the ternary composite, carbon dots-Mg(OH)2-cellulose (CMCel), was examined by experimental characterizations (XRD, FT-IR, SEM, TEM, and XPS) and theoretical computations, along with its immobilization of heavy metal ion (HMI) Pb(II) from wastewater. Using a facile hydrothermal method, the composite material was prepared. It gives a high removal capacity up to 1623.0 mg g–1 towards Pb(II). Moreover, the removal rate maintains almost 99.5% even after 10-cycle operation. The outstanding performance is attributed to synergetic effects of chemically coupled components in the composite. Specifically, interfacial hydrogen bonds are unraveled by density functional theory calculations and experimental characterizations. The HMI removal is well delineated via a pseudo-dynamic process. The in-depth understanding of interfacial behaviors of CMCel is anticipated to advance the design of novel water treatment agents and improve their removal performance towards HMIs.