Photoelectron Storages in Functionalized Carbon Nitrides for Colorimetric Sensing of Oxygen

• DOI: 10.1021/acssensors.2c00961
• Publication Date: 2022-08-01T06:39:36Z
• Authors: Dan Han; Hong Yang; Zhixin Zhou; Kaiqing Wu; Jin Ma; Yanfeng Fang; Qing Hong; Guangcheng Xi; Songqin Liu; Yanfei Shen; Yuanjian Zhang
• Keywords: Chromogenic; Colorimetry; Robustness

Colorimetric sensors have been widely used for centuries across diverse fields, thanks to their easy operation and uncompromisingly high sensitivity with no need electricity. However, it is still a great challenge conventional chromogenic systems perform multiple measurements meanwhile maintaining robustness. Here, we reported that carbon nitrides (CNs), the raw materials are abundant, structure-tunable, stable semiconductors photoelectron storage capability, can be developed as system colorimetric sensors. Beyond metal oxides only demonstrated single blue-color switch after storage, CN exhibited multicolor under identical conditions owing unusual pathways. Mechanism studies revealed cyano carbonyl groups in crucially elongated centroid distance of electrons/holes, which exclusively stabilized specific excited states different light absorption; meanwhile, counter cations strengthened these processes. As result, O2, proof-of-concept analyte, was quantitatively detected by CN-derived sensor, showing reversibility hundreds cycles adaptable sensitivity/detection range, outperforming most commercial oxygen These intriguing features highly envisioned next generation sensors, especially developing countries or fieldworks, improve detection reliability lower sensing cost.