University of Kashan Journal of Nanostructures 2251-7871 15 4 2025 10 01 ZnO-Nanoparticle-Embedded Hydrogel Nanocomposite: A Sustainable Adsorbent for Malachite Green Dye Removal 1751 1758 115024 10.22052/JNS.2025.04.018 EN Aseel M. Aljeboree Department of Chemistry, College of sciences for women, University of Babylon, Iraq Uday Abdul-Reda Hussein Department of Pharmaceutics, College of Pharmacy, University of Al-Ameed, Iraq Hayder Hamid Abbas Al-Anbari College of Pharmacy, Ahl Al Bayt University, Kerbala, Iraq Usama S. Altimari Department of Medical Laboratories Technology, AL-Nisour University College, Baghdad, Iraq Shaimaa Abd Department of Medial Laborites, Al-Manara College For Medical Sciences, Maysan,Iraq Ayad Fadhil Alkaim Department of Chemistry, College of sciences for women, University of Babylon, Iraq Journal Article 2025 06 02 Hydrogels are hydrophilic, cross-linked, three-dimensional polymeric networks that are insoluble and feature high porosity and excellent water retention capabilities. In this work, a hydrogel (sodium alginate/acrylic acid (SA/AC)) and its nanocomposite (SA/AC/ZnO-NPs) were prepared successfully using a co-polymerisation method upon embedment of zinc oxide nanoparticles (ZnO-NPs) with an acrylic acid matrix SEM, and TEM thoroughly characterised the prepared hydrogel/nanocomposite. The adsorption capacity of these sorbents was evaluated in a batch system for the removal of malachite green (MG) dye under various operational conditions, including pH, contact time, and adsorbent dose. The removal efficiency of SA/AC hydrogel increased with the increase in the adsorbent dose, from 76.04% to 93.81%, along with the decrease in q value (777-25.94 mg/g), whereas the SA/AC/ZnO-NPs hydrogel nanocomposite exhibited the removal efficiency of 94.36-98.31%, and the qe value declined from 988.00 to 99.03 mg/g .The adsorption capacity of SA/AC hydrogel increased to 67.05% after 5 minutes of adsorption and to 90% after 40 minutes of adsorption. For the SA/AC/ZnO-NPs nanocomposite, the content increased from 90% to 98% within the same time duration .The higher adsorption efficiency can be attributed to the presence of –COOH groups, which provide strong hydrogen bonding and electrostatic interactions with the cationic dye molecules of MG. The results indicate that the SA/AC hydrogel and SA/AC/ZnO-NPs nanocomposite could be suitable, environmentally friendly adsorbents for removing dyes from wastewater. Nevertheless, the apparent pH-sensitive nature of sodium alginate and ZnONPs can complicate the performance of such materials, especially in the practical world, where precise pH control may not be feasible. https://jns.kashanu.ac.ir/article_115024_6d65a7ba1cead9fa014c50906ff9f67e.pdf