Affiliation:
1. School of Chemistry and Chemical Engineering Hubei Province Key Laboratory for Coal Conversion and New Carbon Materials Wuhan University of Science and Technology Wuhan 430081 P. R. China
2. School of Chemical and Environmental Engineering Wuhan Polytechnic University Wuhan 430023 P. R. China
Abstract
AbstractIt is a significant challenge to develop acidity probes suitable for use in extremely acidic conditions, especially to achieve real‐time on‐site detection. In this work, carbon dots (CDs) are synthesized on a gram‐scale under mild conditions using 3‐phenylpropionaldehyde as precursors. The CDs have excellent robustness, showing distinguished anti‐photobleaching and ionic stability. Dramatically, a visual transition of the fluorescent color of CDs from cyan to orange is observed when the concentration of H+ ([H+]) increased under high acidity conditions, owing to the generation of another emission peak in the red‐light region. Taking advantage of the optical properties, CDs are designed as a ratiometric sensing platform for the detection of extreme acidity. Furthermore, the platform for [H+] possesses high selectivity and excellent anti‐interference capability. In extremely acidic wastewater, I595 nm/I480 nm and [H+] maintain a very good linear relationship (R2 = 0.996). Moreover, a smartphone is employed to obtain the red‐green‐blue (RGB) values of the samples to realize hand‐held detection. By measuring the R/G, the platform exhibits ultrasensitive recognition of [H+] in the range of 1–9 mol L−1 with R2 of 0.992. This work paves an avenue for the design of rapid and on‐site CDs based sensors for critical environmental applications.
Funder
National Natural Science Foundation of China
Subject
Atomic and Molecular Physics, and Optics,Electronic, Optical and Magnetic Materials