Ag/ZnO microcavities with high sensitivity and self-cleaning properties for fast repetitive SERS detection.

A SERS substrate with high sensitivity and reusability was proposed. The chip consists of multiple ZnO microcavities loaded with silver particles. Based on structural characteristics, this coupling between cavity modes and localized surface plasmon modes can highly localize the electric field, where experimental results revealed a detection limit of 10 -11 M for R6G. In addition, during carrier control in semiconductors with localized electromagnetic fields, our substrate also exhibits high self-cleaning efficiency and in situ detection stability. Even in a dry environment, it exhibits excellent light-mediated cleaning ability across multiple reuse test cycles. The convenient, rinse-free substrate, with its cost-effective and sustainable features, shows great promise for the study on detection and degradation of active materials.