碳化氮纳米晶的微波离子热超快合成及其提高的光催化产氢性能
详细信息    查看官网全文
摘要
开发具有优异产氢性能的可见光催化剂是目前光催化剂发展的重要方向,碳化氮因其制备简单、原料廉价、热力学稳定及优异的光催化性能而受到了广泛的关注。但是,碳化氮广泛应用的瓶颈在于其制备一般耗时长,产量低,缩聚程度不可控。针对以上问题,本工作发展了一种微波离子热制备碳化氮纳米晶的有效方法,即:在微波场下,以熔盐为反应介质,以含C、N的有机物为前驱体,通过微波加热的熔盐法超快制备出了具有优异光解水性能的氮化碳纳米晶。采用XRD、UV-vis、FT-IR、Raman、XPS、SEM及TEM等技术对所得样品进行了物相组成、微观结构、化学价态的表征。详细研究工艺参数对碳化氮产物可见光催化产氢性能的影响规律;优化条件下所得氮化碳催化剂的光解水产氢速率可达1.5mmol/(g.h);初步探讨了样品超快合成与产氢性能的相关机制。同普通热聚法及普通熔盐法相比,本工作发展的微波离子热法,缩短了反应时间,提高了产物产率,且提高了产物的光催化产氢性能。
Many strategies have been developed to enhance the performance of photocatalysts for hydrogen evolution via photo-catalytically splitting water. Graphitic carbon nitride(CNx) is a promising photocatalyst and has drawn increasing attention recently. The major challenge for wide application of graphitic carbon nitride is to develop a stable and rapid synthetic method. Herein, we develop a microwave-assisted ionothermal(MWI) method to synthesize graphitic CNx nanocrystals. Using this newly developed method, we achieved unprecedented rapid synthesis of CNx nanocrystals with a high yield(~60 mass %). Under visible-light irradiation, the as-prepared CNxphotocatalyst by the MWI process shows highly enhanced performance of hydrogen evolution, i.e., ~1.5 mmol g~(-1)h~(-1), much higher than that of the carbon nitride sample obtained by common polymerization method(0.1 mmol g~(-1)h~(-1)) or by ionothermal method(0.3 mmol g~(-1)h~(-1)).
引文

© 2004-2018 中国地质图书馆版权所有 京ICP备05064691号 京公网安备11010802017129号

地址:北京市海淀区学院路29号 邮编:100083

电话:办公室:(+86 10)66554848;文献借阅、咨询服务、科技查新:66554700