高性能臭氧分解催化材料的研制及其在新风净化系统中的适用性研究

Outdoor air purification system is a method to refresh the indoor air and fight against the outdoor air pollution. However, the outdoor air purification with the electrostatic precipitator may produce low-level ozone, which may be harmful to human health. The applicant found oxygen vacancies are the key for catalysts such as manganese dioxides to decompose ozone in previous studies. This project aims to further investigate the effects of doping of metal ions such as W, Mo and Al and non-metal ions such N and C, the effect of heat treatment on the oxygen vacancies and surface acidity, exploring the structures of manganese dioxides and their activity for ozone decomposition. And accordingly develop superfine manganese dioxides with surface-rich oxygen vacancies and strong water-resistant property. Porous manganese dioxide composite framework with low air pressure drop would also be prepared. The composite fiber filter for ozone decomposition in outdoor air purification system will be prepared with electrostatic spinning and roller painting. Based on the carbon fiber and aluminum plate which is in-situ coated with high-performance manganese dioxides, develop long-life in-situ electric heating catalytic module for ozone decomposition. The effects of coexisting trace pollutants such as CO and NOx, the change of temperature and relative humidity on the performance of the ozone decomposition module in the outdoor air purification system will be investigated, to develop high-efficiency and stable ozone decomposition module which is suitable for the outdoor air purification system which is run under the complex and variable conditions.

新风净化系统是一种更新室内空气、抵挡室外空气污染的手段，然而采用静电集尘方式的新风净化系统可能产生低浓度臭氧，影响人体健康。申请人前期研究表明氧缺陷是影响二氧化锰这一常用臭氧分解催化材料的关键，本项目将进一步研究W、Mo、Al等金属离子和N、C等非金属离子掺杂、热处理方式等对二氧化锰氧缺陷、表面酸性的影响，探讨二氧化锰结构与其臭氧催化活性的关系，从而研制出表面氧缺陷丰富和抗湿性强的超细二氧化锰基臭氧分解催化剂；研制多孔低风阻、活性位充分暴露的二氧化锰复合框架材料，通过静电纺丝、辊涂等方式制备适合于空气净化系统的臭氧分解复合纤维滤网；通过在碳纤维、铝基材上原位负载高活性二氧化锰，研制长寿命的原位电热臭氧催化分解模块；开展CO、NOx等微量共存污染物、温湿度变化等对新风净化系统中臭氧分解模块使役性能的影响，从而研究开发出适用于新风系统复杂多变条件的高效稳定的臭氧分解模块。

多种来源的低浓度臭氧污染影响人体健康，高性能臭氧分解催化剂是保障公众健康的核心材料，具有广泛的应用需求。为提高催化剂在水蒸气共存条件下的活性和稳定性，本项目从多条技术途径探索二氧化锰（MnO2）和低价锰氧化物的结构调控，包括不同价态金属离子（铈、钒、钨）掺杂、氟掺杂、铵根修饰。研发获得了两种高性能臭氧分解材料——铵根修饰超薄水钠锰矿型MnO2纳米片、铈掺杂Mn2O3。在25 °C、相对湿度50%、空速1200 L/g·h和入口臭氧浓度100 ppm条件下，铵根修饰超薄MnO2纳米片测试6 h后臭氧去除率为97%。成功实现铵根修饰超薄水钠锰矿型MnO2纳米片的每批次公斤级的生产。优化了粉末催化剂在铝蜂窝滤网的负载工艺，研制出高性能、低风阻的铝蜂窝臭氧分解滤网，所制备的铝蜂窝负载催化剂（厚度1cm）在空速3.0 m/s和室温26℃、相对湿度50%时，对进口浓度200 ppb臭氧的一次通过去除率约29.3%，风阻为8 Pa。高性能的铝蜂窝臭氧分解滤网与等离子单元配套应用于北京国二招宾馆等多个建筑物通风系统的消毒，消除了等离子体所产生的臭氧二次污染，保证了等离子体消毒技术的安全。项目负责人作为通讯作者发表SCI源刊论文9篇，获得2项中国发明专利、1项美国专利授权；获得成果应用收入200万元。