Eco-Friendly Cdots-Based Dual-Mode Energy/Electron Transfer Pathways for High-Efficiency p-Nitrophenol Monitoring

As a typical environmental pollutant, the efficient detection of p-nitrophenol (p-Nit) is crucial for ecological protection. In this work, we prepared surface-aminated carbon nanodots (A-Cdots) through choosing precursor monomer and designing reactive process to realize the specific recognition of p-Nit. The superficial amination groups (e.g., -NH₂, -NH-) of the A-Cdots can readily capture nitro-induced strong Lewis acid of free p-Nit through hydrogen bonding; then, the dual-mode electron/energy transfers of inner filter effect between the A-Cdots and p-Nit affect the fluorescence intensity of the A-Cdots, achieving the fluorescent sensing of p-Nit. The large Ksv value (1.0 × 10⁵ M^-1) and the low limit of detection (47 nM) suggest that the A-Cdots can serve as a selective and sensitive fluorescent sensing platform for p-Nit analysis. Importantly, our developed sensor achieves rapid and selective quantification of p-Nit in sewage samples without the need for tedious pretreatment procedures, demonstrating its utility for on-site analysis.