Controlling electronic properties of MoS2/graphene oxide heterojunctions for enhancing photocatalytic performance: the role of oxygen†,Physical Chemistry Chemical Physics

当前位置： X-MOL 学术 › Phys. Chem. Chem. Phys. › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Controlling electronic properties of MoS2/graphene oxide heterojunctions for enhancing photocatalytic performance: the role of oxygen†
Physical Chemistry Chemical Physics ( IF 2.9 ) Pub Date : 2017-12-20 00:00:00 , DOI: 10.1039/c7cp07303h
Xiaotian Hua _{1,

2,

3,

4} , Xinguo Ma _{1,

2,

3,

4,

5} , Jisong Hu _{1,

2,

3,

4} , Hua He _{1,

2,

3,

4} , Guowang Xu _{1,

2,

3,

4} , Chuyun Huang _{2,

3,

4,

5} , Xiaobo Chen _{6,

7,

8,

9}

Affiliation

The manipulation of the constituents of novel hetero-photocatalysts is an effective method for improving photocatalytic efficiency, but a theoretical understanding of the relationship between interlayer interaction and photocatalytic activity is still lacking. Herein, the interfacial interactions and electronic properties of MoS₂/graphene oxide (GO) heterojunctions with various O concentrations were explored systematically by first-principles calculations. The results indicate that MoS₂ and GO can form a stable van der Waals heterojunction, and enhance the built-in internal electric field from GO to the MoS₂ surface with the increase in O concentration after interfacial equilibrium. It is inferred that the photogenerated electrons and holes naturally accumulate in the conduction band of GO and the valence band of MoS₂, respectively, under the built-in internal electric field driving, indicating the formation of direct Z-scheme heterojunctions. In addition, a red shift of the light absorption edge and the shift up of the conduction band edge of MoS₂/GO heterojunctions are observed with an increase in O concentration. It can be concluded that the O atom plays a crucial role in the energy band alignment of MoS₂/GO heterojunctions for the improvement of photocatalytic performance. These results are beneficial to understand and design layered MoS₂/GO photocatalytic systems or as cocatalysts with other semiconductors.

中文翻译：

控制MoS ₂ /氧化石墨烯异质结的电子性质以增强光催化性能：氧的作用†

操作新型杂化光催化剂的成分是提高光催化效率的有效方法，但仍缺乏对层间相互作用与光催化活性之间关系的理论理解。在此，通过第一性原理计算系统地研究了具有不同O浓度的MoS ₂ /氧化石墨烯（GO）异质结的界面相互作用和电子性能。结果表明，MoS ₂和GO可以形成稳定的范德华异质结，并增强从GO到MoS ₂的内置内部电场界面平衡后，随着O浓度的增加，表面变大。可以推断，在内置的内部电场驱动下，光生电子和空穴分别自然地堆积在GO的导带和MoS ₂的价带中，表明形成了直接的Z型异质结。另外，随着O浓度的增加，观察到MoS ₂ / GO异质结的光吸收边缘的红移和导带边缘的上移。可以得出结论，O原子在MoS ₂ / GO异质结的能带排列中对于提高光催化性能起着至关重要的作用。这些结果有助于理解和设计分层的MoS ₂/ GO光催化系统或与其他半导体一起用作助催化剂。

更新日期：2017-12-20

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11