催化学报 ›› 2021, Vol. 42 ›› Issue (7): 1137-1146.DOI: 10.1016/S1872-2067(20)63728-7

• 论文 • 上一篇    下一篇

超薄Ni(OH)2纳米片修饰Zn0.5Cd0.5S纳米颗粒作为二维/零维异质结构光催化剂可见光下光催化制氢

高学友a, 曾德乾a,*(), 杨静仁b, Ong Wee-Junc, Fujita Toyohisaa, 何祥龙a, 刘杰芡a, 韦悦周a   

  1. a广西大学资源环境与材料学院, 广西有色金属及特色材料加工重点实验室, 广西南宁530004, 中国
    b上海交通大学环境科学与工程学院, 上海200240, 中国
    c厦门大学马来西亚分校能源与化学工程学院, 雪兰莪43900, 马来西亚
  • 收稿日期:2020-09-04 接受日期:2020-10-13 出版日期:2021-07-18 发布日期:2020-12-10
  • 通讯作者: 曾德乾
  • 基金资助:
    广西有色金属及特色材料加工重点实验室;广西创新驱动发展专项(科技重大专项)(AA17204100);广西有色金属及特色材料加工重点实验室(AA18118030)

Ultrathin Ni(OH)2 nanosheets decorated with Zn0.5Cd0.5S nanoparticles as 2D/0D heterojunctions for highly enhanced visible light-driven photocatalytic hydrogen evolution

Xueyou Gaoa, Deqian Zenga,*(), Jingren Yangb, Wee-Jun Ongc, Toyohisa Fujitaa, Xianglong Hea, Jieqian Liua, Yuezhou Weia   

  1. aGuangxi Key Laboratory of Processing for Non-ferrous Metals and Featured Materials, School of Resources, Environment and Materials, Guangxi University, Nanning 530004, Guangxi, China
    bSchool of Environmental Science & Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
    cSchool of Energy and Chemical Engineering, Xiamen University Malaysia, Selangor Darul Ehsan 43900, Malaysia
  • Received:2020-09-04 Accepted:2020-10-13 Online:2021-07-18 Published:2020-12-10
  • Contact: Deqian Zeng
  • About author:* Tel: +86-771-3185309; E-mail: dqzeng@gxu.edu.cn
  • Supported by:
    Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured Materials;Scientific Research Startup Foundation of Guangxi University and the Science and Technology Major Project of Guangxi Province(AA17204100);Scientific Research Startup Foundation of Guangxi University and the Science and Technology Major Project of Guangxi Province(AA18118030)

摘要:

设计与制备高效的光解水催化剂是解决能源问题和环境问题的策略之一. 硫化镉因其可在可见光引发下分解水制氢而受到广泛关注, 然而光腐蚀严重, 过电势高, 载流子复合快速以及表面反应动力学缓慢等缺点极大地限制了其在光解水反应中的实际应用. 本文采用简单液相法将均匀的Zn0.5Cd0.5S纳米颗粒锚定在超薄Ni(OH)2纳米薄片上, 构建紧密的二维/零维异质结构. 通过调控Ni(OH)2纳米片的含量, 制备出不同Ni(OH)2质量比(3%, 5%, 7%, 9%, 11%)的二维/零维Ni(OH)2/Zn0.5Cd0.5S复合材料, 并考察其可见光激发的光催化分解水制氢性能.
在可见光照射下, Ni(OH)2/Zn0.5Cd0.5S复合材料的光催化性能要大幅度地优于未修饰的Zn0.5Cd0.5S纳米颗粒, 甚至远高于贵金属Pt修饰的Zn0.5Cd0.5S. 在不同Ni(OH)2含量的纳米复合材料中, 7%Ni(OH)2/Zn0.5Cd0.5S具有最高效的产氢性能, 产氢速率可达6.87 mmol·h-1·g-1, 且在波长为420 nm的表观量子产率为16.8%. 在同等条件下, 二维/零维7%Ni(OH)2/Zn0.5Cd0.5S复合光催化剂的光催化分解水产氢速率分别约为纯Zn0.5Cd0.5S纳米颗粒和Pt/Zn0.5Cd0.5S光催化剂的43倍和8倍, 甚至要高于零维/零维7%Ni(OH)2/Zn0.5Cd0.5S纳米复合材料. 7%Ni(OH)2/Zn0.5Cd0.5S复合光催化剂具有优异的光催化产氢循环性能, 通过循环反应后样品的X射线衍射, X射线光电子能谱和透射电子显微镜等表征, 结果表明Ni(OH)2/Zn0.5Cd0.5S在经过20 h的使用后, 其晶体结构、表面化学成分和形貌结构未发生明显改变. 通过研究样品的时间分辨荧光光谱, 线性扫描伏安响应, 光电流性能及电化学交流阻抗等, 发现二维Ni(OH)2纳米片的修饰能一定程度降低Zn0.5Cd0.5S的过电势, 还能有效促进Zn0.5Cd0.5S的光生电子-空穴的分离和光生电子的转移.
本文认为二维/零维Ni(OH)2/Zn0.5Cd0.5S光催化活性的大幅提升主要由于Zn0.5Cd0.5S与Ni(OH)2之间独特且牢固的纳米结构, 在该过程中超薄Ni(OH)2纳米片不仅能为Zn0.5Cd0.5S纳米颗粒的负载提供平台, 而且作为一种高效的助催化剂, 促进光生电子的转移以及为制氢反应提供更多的活性位点. 本文可为多功能, 高效及低成本的二维-零维异质结构光催化剂的制备及在太阳能转化方面的应用提供一定借鉴.

关键词: 氢氧化镍纳米片, Zn0.5Cd0.5S纳米颗粒, 助催化剂, 二维/零维纳米异质结构, 光催化制氢

Abstract:

Designing and fabricating highly efficient photocatalysts for water splitting is a promising strategy to address energy and environmental issues. Cadmium sulfide (CdS) has received significant interest as a photocatalyst for visible-light-induced hydrogen (H2) generation. However, the severe photocorrosion, high overpotential, rapid charge recombination, and sluggish surface reaction kinetics drastically hinder its practical application in water splitting. Herein, uniform zinc cadmium sulfide (Zn0.5Cd0.5S) nanoparticles were anchored on ultrathin Ni(OH)2 nanosheets via a facile solution-phase approach to form an intimate two-dimensional (2D)/zero-dimensional (0D) heterojunction. Under visible light irradiation, the 7%Ni(OH)2/Zn0.5Cd0.5S composite exhibited the highest H2 production rate of 6.87 mmol·h-1·g-1 with an apparent quantum yield of 16.8% at 420 nm, which is almost 43 times higher than that of pristine Zn0.5Cd0.5S and considerably higher than that of the Pt/Zn0.5Cd0.5S photocatalyst. The high photoactivity of the 2D/0D Ni(OH)2/Zn0.5Cd0.5S heterojunction can be ascribed to its unique and robust structure, wherein the ultrathin Ni(OH)2 nanosheets not only provide an excellent platform for the incorporation of Zn0.5Cd0.5S nanoparticles but also serve as an effective cocatalyst to promote photoinduced electron transfer and offer more active sites for photocatalytic H2 generation. This work paves the way toward the development of versatile, low-cost, and highly efficient 2D/0D heterojunction photocatalysts for solar energy conversion.

Key words: Nickel hydroxide nanosheets, Zn0.5Cd0.5S nanoparticles, Cocatalyst, 2D/0D nanoheterostructures, Photocatalytic H2 generation