Sheetlike gold nanostructures/graphene oxide composites via a one-pot green fabrication protocol and their interesting two-stage catalytic behaviors
Sheetlike gold nanostructures/graphene oxide composites via a one-pot green fabrication protocol and their interesting two-stage catalytic behaviors
复制标题
通过一锅绿色制造方案制备片状金纳米结构/氧化石墨烯复合材料及其有趣的两阶段催化行为
DOI：
10.1039/c7ra11188f
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发表时间：
2017-01-01
期刊：
影响因子：
3.9
通讯作者：
Liu, Minghua
中科院分区：
文献类型：
--
作者：
Geng, Guangwei;Chen, Penglei;Liu, Minghua
具有片状形貌的Au纳米结构由于其在不同领域的潜在应用而引起了极大的关注。虽然在Au纳米片的制造中已经取得了很大的成就，但是大多数当前现有的合成方案通常受到严格的反应条件的要求、特定装置的参与、有害化学品的使用等的影响。强烈期望开始一种容易的、环境友好的但低成本的方法来避免这些问题。在这方面的贡献，我们发现，Au纳米片可以在环境条件下简单地通过混合四氯金酸钾（III），氧化石墨烯（GO）的水分散体的水溶液，和乙醇。有趣的是，我们发现所制备的Au纳米片/GO复合物对NaBH 4诱导的4-硝基苯酚（4-NP）还原显示出迷人的两阶段催化性能，其中后一阶段的催化反应性表现出约1倍的显著增强。与前一阶段相比增加了9倍。我们的研究表明，这种迷人的催化行为可以归因于在第一阶段NaBH 4诱导的π共轭芳香网络的GO的恢复，这促进了电子从GO到Au纳米片的转移，并促进了4-NP在复合物上的锚定，从而导致第二阶段的催化性能的显著提高。这项工作可能不仅介绍了一个简单的，绿色，但低成本的协议，用于合成Au纳米片，但也提供了深刻的见解GO为基础的混合催化剂的催化性能方面的一个有趣的两阶段催化行为。
Au nanoarchitectures shaped with a sheetlike morphology have drawn great attention owing to their potential applications in diverse areas of paramount importance. While great achievements have been made in the fabrication of Au nanoplates, most of the currently existing synthesis protocols generally suffer from either the requirement of rigorous reaction conditions, the involvement of specific apparatus, the use of harmful chemicals, etc. The initiation of an easy, environmentally benign yet low cost method to avoid these issues is strongly desired. In this contribution, we find that Au nanoplates could be fabricated under ambient conditions simply by mixing an aqueous solution of potassium tetrachloroaurate(III), an aqueous dispersion of graphene oxide (GO), and ethanol. Interestingly, we show that the as-manufactured Au nanoplate/GO composite displays fascinating two-stage catalytic performance towards NaBH4-induced reduction of 4-nitrophenol (4-NP), in which the catalytic reactivity of the latter stage exhibits a substantial enhancement by a factor of ca. 9 times compared to that of the former stage. Our investigation suggests that such fascinating catalytic behaviors could be ascribed to the NaBH4-induced restoration of the π-conjugated aromatic network of GO during the first stage, which promotes electron transfer from GO to Au nanoplates and facilitates the anchoring of 4-NPs onto the composites, resulting in the dramatically boosted catalytic performance of the second stage. This work might not only introduce a facile, green yet low-cost protocol for the synthesis of Au nanoplates but also provide deep insights into the catalytic performances of GO-based hybrid catalysts in terms of an interesting two-stage catalytic behavior.