Synthesis of poly (acrylic acid) modified graphene/MoS2 heterostructure-based composite: an effective removal of Pb(II), Cd(II) and Zn(II) from wastewater

• Published in: Scientific reports Vol. 15; no. 1; pp. 11701 - 19
• Main Authors: Olawale, Salami Hammed, Alahmad, Waleed, Darwish, Ibrahim A., Aly Saad Aly, Mohamed, Ashfaq, Mohammad, Kraiya, Charoenkwan
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 05.04.2025; Nature Publishing Group; Nature Portfolio
• Subjects: 639/301; 639/638; 704/172; 704/4111; Acrylic acid; Adsorption; Bioaccumulation; Cadmium; Carbon dioxide; Cations; Cobalt; Contaminants; EIS; Electrostatic properties; Graphene; Heavy metals; Humanities and Social Sciences; Hydrothermal; Isotherms; Lead; Magnesium; Molybdenum; Molybdenum disulfide; MoS2; multidisciplinary; Poly (acrylic acid); Science; Science (multidisciplinary); Temkin; Toxicity; Wastewater pollution; Zinc; MoS; Toxicity; Hydrothermal; Temkin; EIS; Poly (acrylic acid)
• ISSN: 2045-2322; 2045-2322
• DOI: 10.1038/s41598-025-94671-1

Heavy metal contaminants have attracted widespread attention due to their severe toxicity and bioaccumulation. In this study, a novel graphene (EG)/molybdenum disulfide (MoS 2 ) modified with poly (acrylic acid) (PAA) composites (EG/MoS 2 /PAA) were successfully synthesized via a one-step hydrothermal method and effectively removed Pb(II) , Zn(II) , and Cd(II) ions from wastewater. The incorporation of PAA within the EG/MoS 2 significantly improved sorption ability. The EG/MoS 2 /PAA composite was characterized using XRD, FTIR, TEM, Raman, SEM–EDS, EIS, and cyclic voltammetry, which confirmed the successful synthesis of the EG/MoS 2 /PAA composite. The adsorption isotherm and kinetic of Pb(II), Zn(II), and Cd(II) were fitted with the Temkin isotherm and pseudo-second-order model, respectively. The maximum adsorption capacities (q max ) obtained using the Langmuir model were 47.13 mg/g for Pb(II) at pH 5, while 12.59 and 12.89 mg/g for Zn(II) and Cd(II) at pH 7. In the presence of interfering cations (i.e., Na + , Cu 2+ , Co 2+ , Fe 3+ , and Mg 2+ ), the EG/MoS 2 /PAA adsorbent exhibited high selectivity and excellent reusability after three cycles. The adsorption mechanism of Pb(II), Zn(II), and Cd(II) onto the EG/MoS 2 /PAA composite surface was found to be primarily controlled by complexation and electrostatic interaction. This novel EG/MoS 2 /PAA adsorbent has excellent suitability for practical application in the treatment of highly contaminated wastewater.