Coupling the fluorescence and adsorptive properties of biomass-based cellulose–CdS nanocomposite for the alleviation of water contaminants

Abstract

In order to advance the field of environment-friendly nanomaterials, with an objective of the hazardless decontamination of wastewater, a biomass-driven nanocomposite consisting of cellulose nanofibers (CNF) and cadmium sulfide (CdS) was fabricated. The nanocomposite was tested for two potential applications, i.e. fluorescence sensing and adsorption of water toxicants. Its comprehensive characterization revealed the advantageous structural and morphological features of the nanocomposite. The gradual additions of two fluoroquinolones, i.e. ciprofloxacin and ofloxacin, resulted in exceptional enhancement of the fluorescence intensity of the nanocomposite, yielding limits of detection as low as 0.014 μM and 0.040 μM, respectively. The fluorescence scan conditions were optimized in terms of favorable pH, concentration of sensor, contact time, choice of buffer, etc. The biomass-driven nanocomposite was simultaneously tested for its adsorption potential to remove cationic textile dyes, i.e. Rhodamine B, Methylene blue, and Safranin O, and the insecticide Chlorpryifos and exhibited maximum Langmuir adsorption capacities of 27.3222 mg g⁻¹, 21.0562 mg g⁻¹, 9.8039 mg g⁻¹ and 58.1395 mg g⁻¹, respectively. Different adsorption parameters were closely investigated to obtain the optimal conditions for maximum removal of pollutants. The experimental data showed best fits with the Langmuir isotherm and pseudo-second-order kinetics. Development of such multifaceted composites may contribute to the ever-expanding field of sustainable nanomaterials for environmental protection.