摘要
Developed crystal phase-tunable Cu-TiO 2 @g-C 3 N 4 with excellent photoelectric property. • Synergistic MIP-heterojunction system enabled efficient recognition of DOP. • The DOP sensor exhibited a very wide linear range and a femtomolar detection limit. • The new sensor has been successfully applied to detect DOP in the real samples. Di-n-octyl phthalate (DOP), a pervasive endocrine-disrupting contaminant in food packaging, plastic products, and aquatic systems, poses severe threats to ecosystem stability and human health. This work proposed a novel molecularly imprinted polymer (MIP)-integrated photoelectrochemical (PEC) sensing strategy for ultra-selective detection of DOP based on a rationally designed crystal phase tunable Cu 2+ -doped TiO 2 @g-C 3 N 4 composite. By lattice-doping TiO 2 with Cu 2+ to generate impurity energy levels, it was possible to precisely tune its band structure and narrow its bandgap. Subsequently, the obtained Cu-TiO 2 was hybridized with two-dimensional g-C 3 N 4 through energy-level matching, forming a tightly coupled structure at the heterojunction, which had strong interactions and thus opened up directional charge separation and transport channels. The precisely controlled heterogeneous and interfacial properties of the Cu-TiO 2 @g-C 3 N 4 matrix were confirmed through characterization methods such as SEM, TEM, HRTEM, XPS and XRD. The fabricated sensor achieved an extremely wide linear detection range of 10 fM to 1 nM, with an ultra-low limit of detection down to 5.30 fM, alongside exceptional anti-interference capability and practical reliability in real sample assays. This study delivered a low-cost, easily miniaturized PEC-MIP platform for trace DOP monitoring, opening up a new high-performance approach for on-site food safety screening and environmental water quality assessment.
危险品化学品经营许可证（带存储）