In Situ Template-Free Ion-Exchange Process to Prepare Visible-Light-Active g-C3N4/NiS Hybrid Photocatalysts with Enhanced Hydrogen Evolution Activity

详细信息    查看全文

• 作者：Zhihong Chen ; Peng Sun ; Bing Fan ; Zhengguo Zhang ; Xiaoming Fang
• 刊名：Journal of Physical Chemistry C
• 出版年：2014
• 出版时间：April 17, 2014
• 年：2014
• 卷：118
• 期：15
• 页码：7801-7807
• 全文大小：447K
• 年卷期：v.118,no.15(April 17, 2014)
• ISSN：1932-7455

文摘

Nickel sulfide (NiS) and graphitic carbon nitride (g-C₃N₄) hybrid photocatalysts were prepared via a simple and reproducible in situ template-free ion-exchange process. The physical and photophysical properties of the g-C₃N₄/NiS hybrid photocatalysts were characterized by X-ray diffraction (XRD), high-resolution transmission electron microcopy (HRTEM), and ultraviolet visible diffuse reflection spectroscopy (DRS). The photocatalytic hydrogen evolution, photoluminescence spectroscopy (PL), and photoelectrochemical (PEC) experiments indicate that the NiS cocatalysts can efficiently promote the separation of photogenerated charge carriers in g-C₃N₄ and consequently enhance the H₂ evolution activity. The g-C₃N₄/NiS-1.5 mol % sample shows the highest photocatalytic activity, and the corresponding H₂ evolution rate is 44.77 渭mol h^鈥?, which approached that of optimal 2.0 wt % Pt/g-C₃N₄ (47.61 渭mol h^鈥?). A possible photocatalytic mechanism of NiS cocatalysts on the improvement of the photocatalytic performance of g-C₃N₄ is proposed and supported by PL and PEC results. The g-C₃N₄/NiS shows high stable photocatalytic hydrogen evolution ability under visible light irradiation.