稀土纳米材料在光催化二氧化碳还原中的应用  

Rare-Earth Nanomaterials for Photocatalytic Reduction of CO_(2)

作　　者：盘盈滢 李岩岩 郑智平 Pan Yingying;Li Yanyan;Zheng Zhiping(Department of Chemistry,College of Sciences,Southern University of Science and Technology,Shenzhen 518055,China)

机构地区：[1]南方科技大学理学院化学系,广东深圳518055

出　　处：《中国稀土学报》2023年第3期383-403,I0001,共22页Journal of the Chinese Society of Rare Earths

基　　金：国家自然科学基金面上项目(21971106);深圳市稳定支持计划(20200925161141006);南方科技大学科研启动经费及配套经费项目(Y01216127,Y01216227);深圳市诺贝尔科学家实验室-格拉布斯研究院(C17783101)资助。

摘　　要：光催化二氧化碳还原反应(光催化CO_(2)RR)是将惰性CO_(2)转化为高价值化学品的最具前景的策略之一。光催化CO_(2)RR的成功取决于高效催化剂的使用,尽管目前已取得相当的进展,但光催化过程仍面临着光电效应弱和光生载流子易复合等问题,严重制约了CO_(2)还原的效率。稀土离子具有独特的f电子结构和尤其丰富的电子能级,可作为光生电子的“储存器”并兼具抑制光生载流子复合的功能,因此电子能更有效地用于CO_(2)RR。镧系金属离子的强亲氧性和高配位需求,使其易于掺杂进其他氧化物半导体的晶格中,不仅能够稳定半导体复合物的晶相,而且能够有效地调控氧空位的浓度,从而实现半导体光催化剂性能调控和优化。此外,镧系金属亦能以原子级分散方式吸附在半导体表面或实现体相掺杂,直接作为活性位点提升光生电子的传递与利用。本文总结和探讨了稀土纳米材料在光催化CO_(2)RR反应中的不同作用形式,从包括单(纯)稀土半导体材料、负载助催化剂的稀土半导体材料、掺杂稀土半导体材料和稀土半导体-其他半导体的复合材料等四方面进行综述。基于对上述领域已有进展的总结,作者也对该领域面临的挑战进行了小结并对未来研究努力的方向提出了自己的思考和建议。Photocatalytic reduction of CO_(2)(CO_(2)RR) is one of the most promising strategies for converting CO_(2) into value-added products. Its success hinges upon the availability of efficient photocatalysts whose development, not with standing the progress hitherto made, is presently met with their less-than-optimal photoelectric effects and the facile recombination of the photogenerated carriers. Lanthanide ions, characterized with their unique felectronic structures, possess abundant electronic energy levels that may serve as temporary “resting points” for the photogenerated electrons to promote the separation of the carriers while suppressing their recombination. As such, the photogenerated electrons can be utilized more efficiently for CO_(2)RR. Moreover, the high oxophilicity and high coordination-number requirement of lanthanide ions enable ready binding and activation of CO_(2) onto the catalyst, and thus facilitating the subsequent formation of the O-containing intermediates, affording eventually various products of CO_(2)RR. In this review, we survey and discuss the applications of rare-earth nanomaterials, those containing lanthanides in particular, for the photocatalytic reduction of CO_(2). The significant and often essential roles of the rare-earth ions are revealed in four specific types of photocatalysts, including pristine rareearth-based semiconductors, rare-earth-based semiconductors loaded with a cocatalyst, semiconductors doped with rare earth ions, and composites of rare-earth nanomaterials with other semiconductors. A brief summary of the enhancing effects of the rare-earth ions is provided toward the end of this review, which is followed by an account of current challenges and possible corresponding solutions, and pertinent future efforts based on the authors' take of this all-important research field.

关 键 词：稀土 光催化二氧化碳还原 半导体 电子储存器 

分 类 号：TQ426[化学工程] O643.3[理学—物理化学]