光诱导石墨烯等离子共振改善二氧化锰热催化氧化甲醛性能及机制研究

Formaldehyde is one of the main gaseous pollutants in indoor air, which is harmful to people's health. It has become a hot topic to develop efficient formaldehyde removal materials in indoor air purification field. The applicant recently found birnessite-type manganese oxides (i.e. δ-MnO2) could decompose low-level indoor formaldehyde at room temperature. A method was proposed to increase the formaldehyde catalytic activity of birneesite-type MnO2 on the basics of previous investigation. In this project, graphene-based MnO2 hybrid was prepared and investigated for catalytic oxidation of HCHO under light irradiation. The catalytic activity of graphene-based MnO2 hybrid for formaldehyde oxidation was enhanced due to the surface plasmon resonance effect of graphene under near infrared radiation. We will design and fabricate good interface of graphene-based MnO2 hybrid through the structure modification of MnO2 (crystal facet control, doping, fabrication of MnO2 quantum dot) in order to regulate surface electronic state via the interface injection of hot electrons. In addition, relationship between interface structure and the catalytic activity was clarified. This result demonstrates a novel approach to efficiently use the inexhaustible solar energy via the assistance of graphene surface plasmon effect, thus, providing a new thought to improve the catalytic activity of birnessite-type MnO2.

甲醛是室内环境中的主要污染物之一，严重影响人体健康。研究高效去除甲醛的方法已经成为室内空气领域的研究热点。申请人前期的研究发现水钠锰矿二氧化锰（δ-MnO2）可以在室温下分解室内空气中低浓度的甲醛。本项目根据前期的认识，提出了一种增强水钠锰矿对甲醛催化氧化活性的方法。该方法基于石墨烯的表面等离子共振效应，将水钠锰矿与石墨烯复合，利用光照下石墨烯的表面等离子共振的热效应改善二氧化锰的热催化氧化甲醛性能。通过对水钠锰矿结构调控（晶面控制、掺杂、量子点制备），有效设计与构筑良好的石墨烯/二氧化锰界面，实现在微观层面水钠锰矿表面电子的调控并阐明光照条件下石墨烯/二氧化锰界面处热电子的产生及转移机制。本项目利用光照条件下石墨烯的表面等离子共振特性，改善了复合材料的光热转换特性，对于提高二氧化锰的热催化性能提供了一种新的思路。