Green synthesis of Pd@graphene nanocomposite: Catalyst for the selective oxidation of alcohols

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• 作者：Abdulhadi H. Al-Marri^a ; Merajuddin Khan^a ; Mohammed Rafi Shaik^a ; Nils Mohri^b ; Syed Farooq Adil^a ; Mufsir Kuniyil^a ; Hamad Z. Alkhathlan^a ; Abdulrahman Al-Warthan^a ; Wolfgang Tremel^b ; Muhammad Nawaz Tahir^b ; Mujeeb Khan^a ; ^{kmujeeb@ksu.edu.sa" class="auth_mail" title="E-mail the corresponding author} ; Mohammed Rafiq H. Siddiqui^a ; ^{rafiqs@ksu.edu.sa" class="auth_mail" title="E-mail the corresponding author}
• 关键词：Graphene ; Palladium NPs ; Natural products ; Green chemistry ; Catalysis ; Aromatic alcohols oxidation
• 刊名：Arabian Journal of Chemistry
• 出版年：2016
• 出版时间：November 2016
• 年：2016
• 卷：9
• 期：6
• 页码：835-845
• 全文大小：3456 K

文摘

Due to their excellent physicochemical properties and synergistic effect, graphene metallic NPs based nanocomposites have gained significant attention in various technological fields including catalysis. Here we demonstrate a single pot, facile and environmental friendly synthesis of catalytically active palladium(Pd)@graphene nanocomposites (SP-HRG-Pd) by the simultaneous reduction of graphene oxide (GRO) and PdCl₂ using Salvadora persica L. (miswak) root extract (RE) as bioreductant. The synthesis of SP-HRG-Pd was confirmed by various spectroscopic and microscopic techniques, including ultraviolet–visible (UV–vis), Fourier-transform infrared (FT-IR), Raman and X-ray photoelectron (XPS) spectroscopy, X-ray powder diffraction (XRD) and transmission electron microscopy (TEM). The polyphenolic (flavonoids) and terpenoids rich contents of the miswak RE not only facilitated the reduction of graphene oxide and PdCl₂ but also ensured the homogeneous binding of the Pd NPs on graphene, and through stabilization of the surface of SP-HRG-Pd nanocomposites. This also led to the enhanced dispersibility of as synthesized nanocomposites in aqueous solutions. The as-prepared SP-HRG-Pd nanocomposites also demonstrated excellent catalytic activity toward the selective oxidation of aromatic alcohols. Furthermore, in order to study the effect of calcination temperature and concentration of Pd NPs on the catalytic activities of nanocomposites, different samples of SP-HRG-Pd nanocomposites containing different amounts of Pd using various concentrations of Pd precursor were prepared and calcined at various temperatures.