Exploring Adsorption and Reactivity of NH3 on Reduced Graphene Oxide

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• 作者：Eric C. Mattson ; Kanupriya Pande ; Miriam Unger ; Shumao Cui ; Ganhua Lu ; M. Gajdardziska-Josifovska ; Michael Weinert ; Junhong Chen ; Carol J. Hirschmugl
• 刊名：The Journal of Physical Chemistry C
• 出版年：2013
• 出版时间：May 23, 2013
• 年：2013
• 卷：117
• 期：20
• 页码：10698-10707
• 全文大小：379K
• 年卷期：v.117,no.20(May 23, 2013)
• ISSN：1932-7455

文摘

Sensors based on graphene and functionalized graphene are emerging as the state of the art for detecting extremely small quantities of target molecules under realistic working conditions with high selectivity. Although some theoretical work has emerged to understand such adsorption processes (Tang and Cao J. Phys. Chem. C 2012, 116, 8778; Leenaerts et al. Phys. Rev. B 2008, 77, 125416; Tang and Cao J. Chem. Phys. 2011, 134, 044710), little experimental evidence detailing the dynamics of the adsorption and resulting surface species has been reported. Here, we study the adsorption of NH₃ on reduced graphene oxide (RGO) using in situ infrared (IR) microspectroscopy performed under realistic working conditions (i.e., ambient pressure), along with density functional theory (DFT) calculations to support experimental observations. Conclusions drawn from experiment and theory reveal the presence of various surface species that impact the conductivity of the substrate at varying rates. The species arising from adsorption and interactions between NH₃ and RGO include molecularly physisorbed NH₃, as well as chemisorbed fragments such as NH₂, OH, and CH due to dissociation of NH₃ at defects and epoxide groups.