摘要
人工Z-机制光催化剂因其同时具有光吸收范围宽、电荷分离效率高以及载流子氧化还原能力强等优势受到了研究者们的广泛关注.然而,设计和制备能够利用太阳能进行高效光解水产氢的低成本、高稳定性非贵金属Z-机制光催化剂仍具有挑战性.本文报道了一种新颖的全固态Z-机制光催化剂Cd1-xZnxS@WO3-x,该催化剂纳米结构是由氧缺陷WO3-x非晶层包覆Cd1-xZnxS纳米棒组成.研究结果表明,由于适量的Zn掺杂使得Cd1-xZnxS具有更强的产生还原性电子能力,同时, WO3-x超薄非晶层中引入的氧空位(W^5+/OVs)有效地促进了电荷的分离,使得该Z-机制Cd1-xZnxS@WO3-x光催化材料具有优异的光催化产氢反应(HER)活性,且显著高于贵金属Pt负载的Cd1-xZnxS纳米棒(Pt/Cd1-xZnxS及绝大多数WO3和CdS基光催化剂.优化后的Cd1-xZnxS@WO3-x复合光催化剂的HER速率可达21.68 mmol h^-1g^-1.进一步通过原位光沉积负载CoOx和NiO--x双共催化剂, Cd1-xZnxS@WO3-x/Co Ox/Ni Ox复合材料的活性高达28.25 mmol h^-1g^-1,约为Pt/Cd1-xZnxS的12倍.计算结果表明, Cd1-xZnxS@WO3-x在420 nm激发光下的HER表观量子产率(AQY)为34.6%,而负载CoOx和Ni Ox双共催化剂后的Cd1-xZnxS@WO3-x/Co Ox/Ni Ox的AQY提高到了60.8%.此外, Cd1-xZnxS@WO3-x和Cd1-xZnxS@WO3-x/CoOx/NiOx均表现出了良好的长时间HER稳定性.该工作将为理性设计和制备高效光解水产氢催化剂提供新视角.
Artificial Z-scheme photocatalytic systems have received considerable attention in recent years because they can achieve wide light-absorption, high charge-separation efficiency, and strong redox ability simultaneously. Nevertheless, it is still challenging to exploit low-cost and stable Zscheme photocatalysts with highly-efficient H2 evolution from solar water-splitting so far. Herein, we report a novel all-solidstate Z-scheme photocatalyst Cd1-xZnxS@WO3-x consisting of Cd1-xZnxS nanorods coated with oxygen-deficient WO3-x amorphous layers. The Cd1-xZnxS@WO3-x exhibits an outstanding H2 evolution reaction(HER) activity as compared with Pt-loaded Cd1-xZnxS and most WO3- and Cd S-based photocatalysts, due to the generation of stronger reducing electrons through the appropriate Zn-doping in Cd1-xZnxS and the enhanced charge transfer by introducing oxygen vacancies(W^5+/OVs) into the ultrathin WO3-x amorphous coatings. The optimal HER rate of Cd1-xZnxS@WO3- xis determined to be 21.68 mmol h^-1 g^-1, which is further raised up to 28.25 mmol h^-1 g^-1(about 12 times more than that of Pt/Cd1-xZnxS) when Cd1-xZnxS@WO3-x is hybridized by Co Ox and Ni Oxdual cocatalysts(Cd1-xZnxS@WO3-x/CoOx/NiOx)through in-situ photo-deposition. Moreover, the corresponding apparent quantum yield(AQY) at 420 nm is significantly increased from 34.6% for Cd1-xZnxS@WO3-x to 60.8% for Cd1-xZnxS@WO3-x/CoOx/NiOx. In addition, both Cd1-xZnxS@WO3-x and Cd1-xZnxS@WO3-x/CoOx/NiOx demonstrate good stability towards HER. The results displayed in this work will inspire the rational design and synthesis of high-performance nanostructures for photocatalytic applications.
作者
黎艳艳
阮芹芹
林海峰
耿延玲
王婕菲
王辉
杨宇
王磊
Yanyan Li;Qinqin Ruan;Haifeng Lin;Yanling Geng;Jiefei Wang;Hui Wang;Yu Yang;Lei Wang(Key Laboratory of Eco-Chemical Engineering,Taishan Scholar Advantage and Characteristic Discipline Team of Eco-Chemical Process and Technology,Key Laboratory of Rubber-Plastics of Ministry of Education,Shandong Provincial Key Laboratory of Rubber-Plastics,College of Chemistry and Molecular Engineering,School of Polymer Science and Engineering,Qingdao University of Science and Technology,Qingdao 266042,China)
基金
financially supported by the National Natural Science Foundation of China (51572136, 51772162, 21571112, 51802170 and 21801150)
the Natural Science Foundation of Shandong Province (ZR2018BEM014, ZR2018LB008 andZR2019MB001)
Taishan Scholar Foundation of Shandong Province (H. W., ts201712047)
the Special Fund Project to Guide Development of Local Science and Technology by Central Government (H.W.)
Taishan Scholar Program of Advantage and Characteristic Discipline Team of Eco Chemical Process and Technology
关键词
氧化还原能力
光催化剂
光沉积
NIOX
光解水产氢
电荷分离
理性设计
非贵金属
Z-scheme charge transfer
photocatalytic H2 evolution,Cd1−xZnxS solid solutions
oxygen-deficient WO3−x amor-phous layers
CoOx and NiOx dual cocatalysts
