碳量子点-二氧化钛复合光催化剂的研究进展  

Materials Research Progress on Carbon Quantum Dots-Titanium Dioxide Composite Photocatalysts

作　　者：王春来 李钒[1] 杨焜[1] 刘长军[1] 田丰[1] WANG Chunlai;LI Fan;YANG Kun;LIU Changjun;TIAN Feng(Institute of Medical Equipment,Academy of Military Medical Sciences,Tianjin 300161)

机构地区：[1]军事医学科学院卫生装备研究所,天津300161

出　　处：《材料导报》2018年第19期3348-3357,共10页Materials Reports

基　　金：国家自然科学基金(51502345);天津市自然科学基金(16JCQNJC03100)

摘　　要：随着社会的快速发展,环境污染与能源短缺问题日益突出。光催化技术可以利用太阳能降解水体或大气中的污染物,也可用于催化制氢等,是解决环境污染与能源短缺问题最有效的手段之一。二氧化钛(TiO_2)具有光催化活性高、化学性质稳定、价廉、无毒等优点,是当前应用最为广泛的光催化剂。然而,TiO_2的带隙过宽且光生电子与空穴易再结合,因而在光催化领域的应用受到限制。在过去的10多年中,研究者们发展出了一系列方法尝试提高TiO_2的光催化活性,包括量子点敏化、有机染料敏化、TiO_2晶型与形貌的调节、表面贵金属沉积、过渡金属离子掺杂与非金属离子掺杂等。量子点敏化是将TiO_2与量子点复合,从而调节TiO_2的能带宽度,拓宽对光的响应范围。不过,敏化所用的量子点大多含有有毒重金属离子,严重威胁环境与人体健康,这促使许多学者致力于找寻更安全无毒的荧光纳米材料。碳量子点(CDs或CQDs)是一种新型的荧光碳纳米材料,由sp^2/sp^3杂化碳原子组成,表面具有各种官能团。与传统的量子点相比,CDs拥有原料来源广泛、理化性能稳定、无毒、生物相容性好、易于功能化修饰、抗光漂白等优点。此外,CDs还具有光诱导电子转移能力、光敏性以及荧光上转换效应等特性,在光电化学与光催化领域具有良好的应用潜力。将CDs与TiO_2复合制成CDs-TiO_2光催化剂,一方面材料毒性低,克服了传统量子点毒性高的缺点;另一方面能有效抑制光生电子与空穴的再结合,增强对紫外光的吸收并且拓展对可见光甚至近红外光的吸收,从而提高材料的光催化活性。当前研究主要从调控TiO_2与调控CDs两方面入手来提高CDs-TiO_2光催化剂的活性,其中前者主要包括TiO_2晶型和晶面的调节、TiO_2的形貌调控与TiO_2的杂化改性;CDs的调控主要包括CDs的杂化改性、CDs粒径与负载量的调节。�With the photocatalytic technology,people can make further progress in tackling the potential threat of environmental pollution and energy shortage,by effectively utilize solar energy to degrade pollutants in water or atmosphere and to generate hydrogen via photocatalyzed water splitting reactions.Titanium dioxide(TiO 2),currently the most widely used photocatalyst with excellent photocatalytic activity,high chemical stability,low price and non-toxicity,suffers great limitation in application due to its wide band gap and rapid recombination of electrons and holes.Over the past decade or more,researchers have developed a series of methods to improve the photocatalytic activity of TiO 2,including adjusting TiO 2 crystal and morphology,sensitizing TiO 2 using quantum dot or organic dye,depositing precious metal on catalyst surface,doping transition metal ion or non-metal ion.The sensitization of TiO 2 with quantum dot refers to the combination of TiO 2 and quantum dots,which can adjust the band width of TiO 2,broaden the photoresponse range of the photocatalyst.However,the traditional quantum dots mostly contain toxic heavy metal ions,and will no doubt be a hazard to environment and human health.This urges intensive research efforts to seek non-toxic fluorescent nanomaterials,among which carbon quantum dots(CDs or CQDs)have displayed impressive potential and representativeness.CDs,consisting of sp 2/sp 3 hybridized carbon atoms and holding various surface functional groups,enjoy the advantages of abundant ingredient,stable physical and chemical performance,non-toxicity,good biocompatibility,ease of functionalization,and excellent resistance to photobleaching,compared with the traditional quantum dots.In addition,CDs possess photoinduced electron transfer character and photosensitivity,and part of them display excellent up-conversion photoluminescence.By integrating CDs and TiO 2,we can obtain CDs-TiO 2 composite photocatalyst which surpasses the traditional hazardous quantum dots by virtue of its low toxicity.And on

关 键 词：碳量子点 二氧化钛 光催化剂 

分 类 号：TQ174[化学工程—陶瓷工业]