One-pot hydrothermal synthesis of willow branch-shaped MoS2/CdS heterojunctions for photocatalytic H-2 production under visible light irradiation
One-pot hydrothermal synthesis of willow branch-shaped MoS2/CdS heterojunctions for photocatalytic H-2 production under visible light irradiation
复制标题
可见光照射下一锅水热合成柳枝状MoS2/CdS异质结光催化产氢
DOI：
10.1016/s1872-2067(18)63178-x
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发表时间：
2019
影响因子：
16.5
通讯作者：
Li Dong-Sheng
中科院分区：
文献类型：
--
作者：
Zhang Zhen-Wei;Li Qiu-Hao;Qiao Xiu-Qing;Hou Dongfang;Li Dong-Sheng
采用一锅水热法首次合成了杨柳树枝状MoS 2/CdS异质结。通过X射线衍射、X射线光电子能谱、扫描电子显微镜、透射电子显微镜、氮吸附-脱附、漫反射光谱、光电化学和光致发光光谱等测试手段对样品进行了表征。在可见光照射下考察了样品的光催化析氢活性。所得的MoS 2/CdS异质结表现出比CdS和MoS 2获得的更好的光催化析氢活性。特别地，优化的MC-5（5at.% MoS_2/CdS）催化剂的最高产氢速率为250.8 μ molh ~（-1），是未掺杂CdS的28倍。在420 nm处的表观量子效率（AQE）为3.66%。进一步的详细表征表明，MoS 2/CdS异质结的光催化活性的增强可能归因于核壳结构和MoS 2纳米片与CdS单晶纳米棒之间的紧密接触所产生的光生载流子的有效转移和分离，以及可见光吸收的增加。提出了MoS 2/CdS异质结光催化析氢的初步机理。这项工作将为开发更有效的水分解光催化剂开辟新的机会。
Willow branch-shaped MoS2/CdS heterojunctions are successfully synthesized for the first time by a facile one-pot hydrothermal method. The as-prepared samples were characterized by X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, nitrogen adsorption-desorption measurements, diffuse reflectance spectroscopy, and photoelectrochemical and photoluminescence spectroscopy tests. The photocatalytic hydrogen evolution activities of the samples were evaluated under visible light irradiation. The resulting MoS2/CdS heterojunctions exhibit a much improved photocatalytic hydrogen evolution activity than that obtained with CdS and MoS2. In particular, the optimized MC-5 (5 at.% MoS2/CdS) photocatalyst achieved the highest hydrogen production rate of 250.8 μmol h-1, which is 28 times higher than that of pristine CdS. The apparent quantum efficiency (AQE) at 420 nm was 3.66%. Further detailed characterizations revealed that the enhanced photocatalytic activity of the MoS2/CdS heterojunctions could be attributed to the efficient transfer and separation of photogenerated charge carriers resulting from the core-shell structure and the close contact between MoS2nanosheets and CdS single-crystal nanorods, as well as to increased visible light absorption. A tentative mechanism for photocatalytic H2evolution by MoS2/CdS heterojunctions was proposed. This work will open up new opportunities for developing more efficient photocatalysts for water splitting.