The Effectiveness of Boron and Halide Modified Carbon Nanoparticles (CNPs) for Detecting Polystyrene Microplastics in Aquatic Environments
Dzakiyach Aufa Furqony1,a*, Lina Mahardiani1,b

1Department of Chemistry Education, Faculty of Teacher Training and Education, Universitas Sebelas Maret, Indonesia.

Abstract

Carbon nanoparticles (CNPs) are nanoparticle materials with excellent fluorescence properties and potential applications as sensors. This study aims to investigate the effectiveness of boron and halide (Cl, Br, and I) modified CNPs for the detection of polystyrene microplastics in aquatic environments. The CNPs were synthesized using HNO3 via solvothermal method at 200 C, with pyrene as the carbon source, and subsequently modified with H3BO3, HCl, HBr, and HI. The synthesis produced black powder samples denoted as B-PN, Cl-PN, Br-PN, and I-PN. FTIR analysis confirmed the presence of aromatic ring functional groups of nitrated pyrene, C-B bonds in B-PN, and C-X (halide) bonds in Cl-PN, Br-PN, and I-PN. XRD results indicated that boron and halide doping reduced both the crystallite size and degree of crystallinity due to crystal structure distortion. Photoluminescence analysis showed emission peaks at wavelengths of 500-510 nm, corresponding to the green spectral region. Under UV irradiation at 365 nm, boron and halide doped CNPs were able to detect polystyrene microplastics under various dopant types, solvents, detector masses, and aqueous conditions. The strongest fluorescence emission was observed when nonpolar solvents and larger detector sample masses were used, attributed to van der Waals forces and pi-pi interactions between polystyrene and CNPs. These findings demonstrate that boron and halide modified CNPs have strong potential as simple and effective sensors for the detection of polystyrene microplastics in both aquatic and non-aquatic environments.

Keywords: carbon nanoparticles, pyrene, microplastics, sensor, photoluminescence

Topic: Physical Chemistry