Effect of carbon dot on preparation of dual-functional Janus particles via photo-initiated seed swelling polymerization

With the development of industry, the detection and removal of heavy metal ions from water has received much attention. Janus particles are distinguished from many other materials by their unique structure and functionalization. We proposed a simple photo-initiated seed swelling polymerization method for preparing carbon dot-coated dual-functional Janus particles (Janus@CD), using glycyl methacrylate (GMA) as monomer and ethylene dimethacrylate (EDMA) as crosslinker. In order to modulate the particle morphology during the phase separation process, carbon dot (CD) was added to the reaction system. The results demonstrated that the presence of CD had a significant effect on the shape of Janus particles. Furthermore, Janus@CD could be directly applied in the adsorption and detection for MnO₄⁻. The limit of detection (LOD) was 6.39 nmol L⁻¹, and the maximum adsorption capacity was 23.9 mg g⁻¹, in line with the Langmuir adsorption model. The adsorption equilibrium reached within 30 min. The results demonstrated that dual-functional Janus@CD would present great potential in the detection and enrichment for metal ions.