采用氮和硫元素共掺杂的水热法合成了一种发蓝光的碳点.经过一系列的光学和微观结构表征分析，发现氮和硫元素可以通过杂原子掺杂和表面官能团的形式充分参与到碳点中，这决定了所制备的蓝光碳点拥有最高54.27%的量子产率.由于其高效荧光，该碳点可以用作传感探头检测金属离子，且对Ag⁺和Fe³⁺具有高灵敏度和选择性，通过Stern-Volmer方程拟合发现，随着离子浓度的变化，两种金属离子不同的淬灭机制和检测极限为在实践中有效检测和区分Ag⁺和Fe³⁺提供了一种可行的新方法.

A carbon dots with blue light was synthesized by the N and S co-doped hydrothermal method. After a series of optical and micro-structural characterizations, N and S elements could be sufficiently doped by means of the heteroatom and functional groups on the surface of the carbon dots, which decided as-prepared carbon dots to emit blue color fluorescence with the highest quantum yield of 54.27%. Owing to the strong fluorescence, the as-prepared carbon dots can be used as a sensing probe for the detection of Ag⁺ and Fe³⁺ with high sensitivity and selectivity. Both ions possessed different quenching mechanism and limit of detection with the variation of the ionic concentration through the fitting by Stern-Volmer equation, providing a new approach for efficient detection of Ag⁺ and Fe³⁺ for the application.