石墨烯-铋系氧化物复合光催化材料

Graphene-bismuth based oxide composite photocatalytic materials

当前环境和能源问题越来越突出,以TiO2为代表的半导体光催化剂能够有效利用太阳能,为解决这方面问题提供了可能,其中铋系氧化物具有较高的可见光催化活性,近年来受到广泛关注。石墨烯是2004年发现的一种新型二维碳纳米材料,利用石墨烯优良的导电性能和较高的比表面积使之与铋系氧化物复合,从而提高铋系氧化物的光催化性能,是当前光催化研究领域的热点之一。相较于离子掺杂、半导体复合,它能够避免在铋系氧化物内部形成新的缺陷(光生电子空穴复合中心)。阐述了石墨烯在增强铋系氧化物光催化性能方面的最新研究进展和成果,综述了石墨烯复合对铋系氧化物的影响,即石墨烯的复合会使铋系氧化物吸光性增强,比表面积增加,光生电流增强,且光催化效率与石墨烯负载量之间存在极值关系;分析了石墨烯与铋系氧化物之间的化学键对其光催化性能的影响。最后,从石墨烯-铋系氧化物的制备、化学键合作用等方面展望了其发展趋势。

Currently,environmental and energy issues become increasingly prominent.TiO2 ,the representative semiconductor photocatalyst,can use solar energy efficiently and provide possibility to solve such problems in this area.Among the reported photocatalysts,bismuth-based oxide with high visible light driven photocatalytic activity attracted widespread attention in recent years.On the other hand,in 2004,graphene was found as a new type of two-dimensional carbon nanomaterials and has been attracted more and more attention owing to its unique physical and chemical properties.Utilizing its excellent conductivity and high specific surface area to in-crease the photocatalytic activities of bismuth-based oxide has been extensively studied.Compared to the ion do-ping and coupling with other semiconductors,it was possible to avoid the formation of new internal defects (photo-generated electron-hole recombination centers)in bismuth-based oxide.Our review summarized the pro-gress of graphene enhancing photocatalytic properties of bismuth-based oxide,especially the effects of graphene on bismuth-based oxide including graphene enhancing the specific surface area,light absorption,photocurrent of bismuth-based oxide.The optimized ratios between graphene and bismuth-based oxide were required.More-over,the effects of chemical bands between graphene and bismuth-based oxide on photocatalytic performance were discussed.Finally,the development trend was prospected based on the preparation of graphene/bismuth-based oxide and the effects of chemical bands.