Gold-Palladium Nanoalloys Supported by Graphene Oxide and Lamellar TiO2 for Direct Synthesis of Hydrogen Peroxide
Gold-Palladium Nanoalloys Supported by Graphene Oxide and Lamellar TiO2 for Direct Synthesis of Hydrogen Peroxide
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氧化石墨烯和层状二氧化钛负载金钯纳米合金直接合成过氧化氢
DOI：
10.1021/acsami.8b17342
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发表时间：
2018
影响因子：
9.5
通讯作者：
Li Gao
中科院分区：
文献类型：
--
作者：
Guo Song;Zhang Shaohua;Fang Qihua;Abroshan Hadi;Kim Hyung J.;Haruta Masatake;Li Gao
采用沉积-还原法制备了由金钯纳米合金夹在氧化石墨烯（GO）和片状TiO 2之间的复合催化剂。通过X射线衍射、扫描透射电子显微镜、X射线光电子能谱和电感耦合等离子体质谱等一系列技术对不同金属和载体组成的AuPd催化剂进行了表征。该催化剂还针对Au，Pd，GO和TiO 2的内容进行了优化，并用于从H2和O2直接合成过氧化氢（DSHP）。由1wt%的Au和Pd等摩尔混合物纳米颗粒、6wt%的GO和93wt%的TiO 2组成的类金钯纳米合金对DSHP反应显示出有希望的催化性能，H2 O2的产率和选择性分别为5.50 mol H2 O2 g金属-1 h-1和64%。发现该催化剂比文献中报道的催化剂活性高得多。此外，HNO 3预处理后，催化剂的H2 O2选择性明显提高到88%。结果表明，AuPd合金与TiO 2界面的周边位置是DSHP反应的催化活性中心，TiO 2的酸性可以抑制其他反应的进行和H2 O2的分解.本研究的结果可以提供一个设计策略，部分覆盖的催化剂是由二维材料限制的选择性反应。
Hybrid catalysts composed of gold–palladium nanoalloys that are sandwiched between layers of graphene oxide (GO) and lamellar TiO2are synthesized via the deposition–reduction method. The resulting AuPd catalysts with different compositions of metal and support are fully characterized by a series of techniques, including X-ray diffraction, scanning transmission electron microscopy, X-ray photoelectron spectroscopy, and inductively coupled plasma mass spectrometry. The catalysts are also optimized against Au, Pd, GO, and TiO2contents and employed in the direct synthesis of hydrogen peroxide (DSHP) from H2and O2. The sandwich-like AuPd nanoalloy comprising 1 wt % nanoparticle of an equimolar mixture of Au and Pd with 6 wt % GO and 93 wt % TiO2supports shows a promising catalytic performance toward the DSHP reaction with H2O2productivity and selectivity of 5.50 mol H2O2gmetal–1h–1and 64%, respectively. The catalyst is found to be considerably more active than those reported in the literature. Furthermore, the H2O2selectivity of the catalyst is found to improve considerably to 88% when the TiO2support is pretreated by HNO3. It is found that the perimeter sites of the interface of AuPd alloy and TiO2are deemed as catalytically active sites for the DSHP reactions and the acidic property of TiO2can retard the other overreactions and the decomposition of yielded H2O2. Results of the present study may provide a design strategy for partially covered catalysts that are confined by 2D materials for selective reactions.