ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Eco-friendly fabrication of a floatable alginate-supported bentonite-gC₃N₄ photocatalyst for environmental remediation

G. Syed Maroof, MD Furqaan Valiyathur, Mohammed Rehan Katiyan, Anver Basha Kottur, Z. Ansar Ali, and Mohammed Safiullah Sakvai

P.G. and Research Department of Chemistry, C. Abdul Hakeem College (Autonomous), (Affiliated to Thiruvalluvar University), Melvisharam, India

E-mail: pzansarali@gmail.com

Received: 27 November 2025  Accepted: 29 May 2026

Abstract:

Developing high-performance, easily recoverable photocatalysts remains a critical challenge in sustainable wastewater treatment. In this study, a novel self-floating alginate-based photocatalyst, Bent-gC₃N₄/Alg, was engineered by anchoring a Bentonite-graphitic carbon nitride (g-C₃N₄) composite into an alginate matrix via ionic crosslinking process. The novelty of this architecture lies in the strategic use of alginate and nano-Bentonite as a structural intercalator that prevents g-C₃N₄ agglomeration while creating a synergistic interface that dramatically narrows the bandgap from 2.46 to 1.91 eV. This electronic modulation significantly extends visible-light harvesting and suppresses charge carrier recombination. Furthermore, the engineered buoyancy of the hydrogel matrix enables rapid, tool-free recovery from the water surface, avoiding the energy-intensive filtration or centrifugation required for conventional powdered catalysts. Physicochemical characterization using FTIR, XRD, UV-Vis DRS, SEM-EDAX, and BET confirmed successful composite formation and favourable surface morphology. Under visible-light irradiation, the floating photocatalyst achieved 97% degradation of Methylene Blue within 70 min. Reusability tests over five successive cycles demonstrated excellent structural integrity and consistent performance, confirming that the Bent-gC₃N₄/Alg represents a novel, scalable, and eco-friendly platform for efficient solar-driven environmental remediation.

Keywords: Bentonite; Alginate; g-C3N4; Floatable beads; Sustainability

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-026-05135-3

Chemical Papers 80 (10) 12365–12381 (2026)