اشترك بالحزمة الذهبية واحصل على وصول غير محدود شمرا أكاديميا
تسجيل مستخدم جديدPreparation and Characterization of Metal-free graphitic Carbon Nitride Film Photocathodes for Light-induced Hydrogen Evolution
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Very recently, it has been shown that an abundant material, polymeric carbon nitride, can produce hydrogen from water under visible-light irradiation in the presence of a sacrificial donor [1]. We will present here the preparation and characterization of graphitic carbon nitride (g-C3N4) films on semiconducting substrates by thermal condensation of dicyandiamide precursor under inert gas conditions. Structural and surface morphological studies of the carbon nitride films suggest a high porosity of g-C3N4 thin film consisting of a network of nanocrystallites. Photo-electrochemical investigations show upon cathodic polarization light-induced hydrogen evolution for a wide range of proton concentrations in the aqueous electrolyte. Additionally, Synchrotron radiation based photoelectron spectroscopy has been applied to study the surface/near-surface chemical composition of the utilized g-C3N4 film photocathodes. For the first time it is shown that g-C3N4 films can be successfully applied as photoelectrochemical material for light induced hydrogen evolution. [1]X. Wang, K. Maeda, A. Thomas, K. Takanabe, G. Xin, J. M. Carlsson, K. Domen, M. Antonietti, Nature Mat. 2009, 8, 76-80.
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