Imaging the reactivity of carbon nitride nanosheets by photoinduced cathodic electrochemiluminescence microscopy

Carbon nitride (CN) is a highly promising electrochemiluminescence (ECL) nanomaterial operating in aqueous media at physiological pH. Here, we report the upconversion photoinduced ECL (PECL) emission on a p-type Si modified with CN nanosheet (p-Si/CNNS) photocathode in aqueous solution. The PECL activity of the single micrometer-sized CNNS was directly imaged by microscopy, revealing the heterogeneity at the single-particle level. In addition, the reported approach allows decreasing the onset ECL potential to -0.47 V vs. Ag/AgCl. This study opens new avenues for light-addressable electrochemical systems, the optimization of CNNS reactivity, and the study of new ECL materials.