Harnessing synergy: Polydopamine-hBN integration in electrospun nanofibers for Co (II) ion, methylene blue and crystal violet dyes adsorption

Abstract

In today's world, major pollutants, such as cationic dyes and heavy metals, pose a serious threat to human health and the environment. In this study, a novel adsorbent was created through the electrospinning of polyvinyl alcohol/polyacrylic acid (PVA/PAA), incorporated with hexagonal boron nitride (hBN) coated with polydopamine (PDA). The integration of hBN and PDA substantially enhanced the adsorption capacity of the PVA/PAA fibers, making them highly effective in adsorbing cationic dyes such as methylene blue and crystal violet, as well as cobalt (II) ions, from contaminated water. The adsorbents were assessed to understand how their adsorption behavior varies with pH, as well as to examine their adsorption kinetics and isotherms. The results indicate that the PVA/PAA-hBN@PDA adsorbent has maximum adsorption capacities of 1029.57 mg/g, 793.65 mg/g, and 62.46 mg/g for methylene blue, crystal violet, and cobalt (II) ions, respectively. This underscores the superior performance of the PVA/PAA-hBN@PDA adsorbent when compared to both the PVA/PAA and PVA/PAA-hBN adsorbents. The adsorption kinetics adhered to a pseudo-second-order model, indicating chemisorption, whereas the Langmuir model implied a monolayer adsorption. Overall, the findings of this study highlight the efficacy of harnessing the synergistic capabilities of hBN and PDA within the PVA/PAA-hBN@PDA adsorbents, providing an efficient and eco-friendly approach to removing cationic dyes and heavy metals from contaminated water, and thereby contributing to a cleaner and safer environment for all.