The W@WO3 ohmic contact induces a high-efficiency photooxidation performance.
The W@WO3 ohmic contact induces a high-efficiency photooxidation performance.
复制标题
DOI：
10.1039/c6dt04387a
复制
发表时间：
2017-01
影响因子：
4
通讯作者：
Fangxu Wan;L. Kong;Changhua Wang;Yingying Li;Yichun Liu;Xintong Zhang
中科院分区：
文献类型：
--
作者：
Fangxu Wan;L. Kong;Changhua Wang;Yingying Li;Yichun Liu;Xintong Zhang
肖特基型金属-半导体（M-S）结在促进光生载流子的分离方面表现良好。在本文中，通过酸部分氧化策略开发了另一种类型的 M-S 结，即 W@WO3 的欧姆接触。通过简单地调整酸浓度和反应时间等实验参数，WO3纳米片就可以在W核上外延生长；此外，WO3壳的厚度和密度可以精细控制。通过紫外光照射下气态乙醛的降解来测试样品的光催化活性。结果表明，WO3壳层更薄、更疏松的W@WO3核壳复合材料表现出更高的乙醛矿化二氧化碳的能力。通过光电测量充分证实了 W 核和 WO3 壳之间的欧姆接触。据认为，欧姆接触界面处的内建电场导致光生电子从WO3迁移到W，这有利于电子-空穴对的分离，从而增强光氧化能力。
The Schottky-type metal-semiconductor (M-S) junction works well in promoting the separation of photogenerated carriers. In this paper, another type of M-S junction, Ohmic contact of W@WO3, has been developed via an acid partial oxidation strategy. By simply tuning the experimental parameters including the acid concentration and the reaction time, WO3 nanosheets are epitaxially grown on a W core; moreover, the thickness and density of the WO3 shell can be finely controlled. The photocatalytic activities of samples are tested via degradation of gaseous acetaldehyde under UV light irradiation. The results show that the W@WO3 core-shell composite with a thinner and looser WO3 shell exhibits a higher mineralization ability of acetaldehyde to carbon dioxide. An Ohmic contact between the W core and the WO3 shell is fairly confirmed by means of photo-electronic measurements. It is believed that the built-in electric field at the interface of the Ohmic contact leads to the migration of photogenerated electrons from WO3 to W, which is beneficial for separation of the electron-hole pairs and hence an enhanced photooxidation ability.