Sites for High Efficient Photocatalytic Hydrogen Evolution on a Limited-Layered MoS2 Cocatalyst Confined on Graphene Sheets鈥昑he Role of Graphene

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• 作者：Shixiong Min ; Gongxuan Lu
• 刊名：The Journal of Physical Chemistry C
• 出版年：2012
• 出版时间：December 6, 2012
• 年：2012
• 卷：116
• 期：48
• 页码：25415-25424
• 全文大小：580K
• 年卷期：v.116,no.48(December 6, 2012)
• ISSN：1932-7455

文摘

The development of an advanced cocatalyst is critical for improving the efficiency of the photocatalytic hydrogen evolution reaction. Noble metals such as platinum (Pt) have been identified to be the most active cocatalyst for this reaction; however, due to their low-abundance, high cost, their usage in the scale-up setup is impeditive. Here, we report a high active cocatalyst, limited-layered MoS₂ confined on RGO sheets as an alternative of Pt, for hydrogen evolution in dye-sensitized photocatalytic systems. Growing a MoS₂ cocatalyst on RGO sheets provides more available catalytically edge sites and thus exhibits much higher activity than large aggregated pristine MoS₂ particles under visible light irradiation (鈮?20 nm). The apparent quantum efficiency (AQE) of 24% at 460 nm over an Eosin Y-sensitized MoS₂/RGO photocatalyst has been achieved. In addition, the electrical coupling and synergistic effect between MoS₂ and RGO sheets greatly facilitate the efficient electron transfer from photoexcited dye to the active edge sites of MoS₂; as a result, the prolonged lifetime of photogenerated electrons and the improved charge separation efficiency have been accomplished, and the photocatalytic hydrogen evolution activity has been enhanced significantly. This work demonstrates that the structural integration of MoS₂ with RGO will be a new promising strategy to develop a high efficient and low-cost non-noble metal cocatalyst for solar hydrogen generation.