Synthesis and characterisation of novel beta-cyclodextrin based Fe₃O₄ nanocomposite: adsorption behaviour and photocatalytic dye degradation studies

ABSTRACT

Novel Beta-Cyclodextrin-based Fe₃O₄ nanocomposite has been synthesised through copolymerisation by incorporating Fe₃O₄ nanoparticles into the polymer matrix. Ultraviolet-Visible (UV-Visible) spectroscopy, Fourier transform infrared (FTIR) spectroscopy, Thermogravimetric (TGA) analysis, Point of Zero Charge, X-ray diffraction (XRD), and Scanning electron microscopy (SEM) analysis have been used to characterise the Fe₃O₄ Nanoparticles and β-CDHs@Fe₃O₄ nanocomposite. The synthesised β-CDHs@Fe₃O₄ nanocomposite has been utilised for the adsorption of methylene blue (MB) dye from aqueous solutions. The maximum percentage removal of MB dye at optimum pH 7 and was found to be 98.51%. The adsorption capacity (q_e) of β-CDHs@Fe₃O₄ nanocomposite has been found to be 268.09 mg/g at optimum dosages 1.2 g/L, pH 7, temperature 25°C, concentration 100 mg/L and an agitation speed of 200 rpm. Adsorption data have been fitted with three isotherm models namely Langmuir, Freundlich, and Temkin, and it was found to be the best fit with the Langmuir isotherm model. Kinetic studies like the pseudo-first order, pseudo-second order, and intra-particle diffusion model were also performed to study the adsorption mechanism. Further, thermodynamic studies demonstrate that the reaction was exothermic and spontaneous. Photocatalytic degradation of MB dye under visible light has also been studied, and 79.01% degradation of the dye was observed. Also, desorption of the nanocomposite was performed, and it was found to be reusable up to 5 times with 90% dye-desorption in the fifth cycle.

KEYWORDS:

• Beta-Cyclodextrin
• Fe₃O₄ nanoparticles
• beta-CDHs@Fe₃O₄ nanocomposite
• methylene blue dye removal
• adsorption
• reusability

Acknowledgments

The authors are grateful to the Vice Chancellor, Madan Mohan Malaviya University of Technology, Gorakhpur for providing the necessary facilities for the present work. The authors would like to acknowledge the Central Advanced Facilities for Materials Characterization (CAFMC), Prof. Rajendra Singh (Rajju Bhaiya) Institute of Physical Sciences for Study and Research, VBS Purvanchal University, Jaunpur.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Author contribution

Dr. Poorn Prakash Pande contributed to overall supervision, editing and reviewing of the manuscript. Mr. Arbind Chaurasiya was involved in the data planning, operating software, and participated in the writing, reviewing, and editing processes. Miss. Nandita Kushwaha was involved in calculation, writing and editing. Dr. Kajal Kumar Dey provided characterisation data.

Data availability statement

Additional data will be provided by the corresponding author upon request.