Liquid/Liquid Interface-Assisted Synthesis of Two-Dimensional Metal Networks with High-Density Planar Defects for Electrocatalysis

A metal nanonetwork with high-density planar defects isan attractive candidate for highly efficient electrocatalysts due to its fastelectron transfer capability and abundant active sites. However, itsfabrication has met with limited success by far. Herein, we report aliquid/liquid interface-assisted synthesis of two-dimensional (2D)palladium (Pd) networks with high-density planar defects and theirsuperior catalytic performance for the methanol oxidation reaction(MOR). The successful preparation of 2D Pd networks mainly relieson the combination of etching and regrowth of Pd nanocrystalsassembled on the water/chlorobenzene interface. Using different metalnanocrystals as the starting materials, we could further extend themethod for preparing 2D gold (Au) and palladium-gold (Pd-Au)bimetallic networks. During the MOR, the 2D Pd network coulddeliver much enhanced activities relative to the pristine nanocubes, with a factor of 3.7 and 2.3 enhancement in specific activity andmass activity, respectively, due to the network structure and high-density planar defects.