Metal-Nanoparticles-Loaded Ultrathin g-C 3 N 4 Nanosheets at Liquid–Liquid Interfaces for Enhanced Biphasic Catalysis

作者：Yajuan Hao, Shijiao Hao, Qibiao Li, Xian Liu, Houbing Zou, Hengquan Yang · 发表于：ACS Applied Materials & Interfaces · 年份：2021 · DOI：10.1021/acsami.1c13903 · 被引用次数：34 · 研究领域：Pickering emulsions and particle stabilization、Gold and Silver Nanoparticles Synthesis and Applications、Nanocluster Synthesis and Applications

Exploiting new interface-active solid catalysts is crucial to construct efficient Pickering emulsion systems for biphasic catalysis. In this work, ultrathin g-C 3 N 4 nanosheets (g-C 3 N 4 -NSs) were developed as a new solid emulsifier to directly position catalytic sites at oil–water interfaces for improving the reaction efficiency of a biphasic reaction. Exemplified by a metal-involved biphasic reaction of nitroarenes reduction, the developed Pd/g-C 3 N 4 -NSs catalyst with Pd nanoparticles loaded on the surface of g-C 3 N 4 -NSs exhibited excellent activity with a catalytic efficiency of 1220 h –1 . Such activity was 4.2 and 17.9 times higher than those of Pd/g-C 3 N 4 -bulk and the ordinary Pd/C 8 -SiO 2 catalyst, respectively. Also, in the biphasic oxidation reaction of alcohols, Pd/g-C 3 N 4 -NSs achieved a 2.3-fold activity enhancement. It was found by analyzing the solidified emulsion droplets that the Pd/g-C 3 N 4 -NSs catalyst was parallelly assembled at the oil–water interfaces. Because of the ultrathin thickness of g-C 3 N 4 -NSs, such a unique interfacial assembly behavior allowed precise positioning of Pd nanoparticles at the oil–water interfaces. As a result, the oil-soluble reactant could directly react with the water-soluble reactant at the oil–water interface hosting the Pd nanoparticles. Our elaborately designed reaction interface was believed to substantially avoid the diffusion barrier between oil-soluble and water-soluble reactants and then to significan...