甲醛是室内空气污染的主要来源，为减少其对身体健康带来的危害，对其准确实时的监测十分必要，最为简便快捷的监测方法是气敏传感器，但目前该类传感器在性能等方面仍存在诸多问题。本项目拟在前期分子印迹Ag-LaFeO3甲醛气敏材料研究的基础上，采用石墨烯量子点（Graphene Quantum Dots， GQDs）进行改性，研究粒度可控的富氧官能团石墨烯量子点（O-GQDs）的控制合成工艺、O-GQDs对分子印迹Ag-LaFeO3的改性方法，以及不同粒度、不同氧含量及不同浓度的GQDs改性对甲醛气敏性能的影响规律；分析改性影响甲醛吸附、器件电阻及电子传输等的微观作用机制，获得工作于室温的高灵敏度、高选择性的甲醛气敏传感材料与器件，克服目前该类器件存在的工作温度高、选择性和灵敏度不理想、难以实用化等问题。该研究也对GQDs应用于其它气敏传感器以提高气敏性能提供新的思路。

Formaldehyde is the main source of indoor air pollution. In order to reduce its harm to the human health, accurate real-time monitoring is very necessary. The most convenient and fast monitoring method is gas sensors, but there are still some deficiencies exist in the properties of the sensors. This project aims to use graphene quantum dots (GQDs) to modify molecular imprinted Ag-LaFeO3 formaldehyde gas sensing materials based on previous work. The size controllable synthesis process in size and rich-oxygen graphene quantum dots (O-GQDs) will be studied, and also the modification method of O-GQDs to molecular imprinting Ag-LaFeO3 will be researched. The influence of doping GQDs with different size, different oxygen content and different concentration on formaldehyde gas sensing properties will be analyzed. On the basis of above, the mechanism of the formaldehyde adsorption, device resistance and electronic transmission after modified with GQDs will be clarified. The formaldehyde sensing materials and sensors with high selectivity, high sensitivity and operated at room temperature will be obtained, and the problems of high operating temperature, unsatisfactory sensitivity and selectivity will be overcomed. The study also provides new ideas for the application of GQDs in the other gas sensors to improve gas sensing properties.