1st Paragraph: Many studies have shown that Pd-based nanocrystals (NCs) with multifarious nanoarchitectures from zero to three dimensions represent comparable or even higher catalytic activity for liquid fuel oxidation or oxygen reduction reaction and greater resistance to CO poisoning than that of Pt [1, 2]. Among them, hollow NCs (HNCs) have sparked tremendous research attention for their cost-saving feature . Owing to its high utilization of noble metal, high surface-to-volume ratio, void interior and high porosity, Pd-based NCs with hollow features present great potential as efficient catalysts in fuel cell technologies . Besides, a series of previous work has demonstrated that the rough dendritic architecture highly favour desirable high mass-activity of noble metal NCs . It would be greatly advantageous to prepare dendritic NCs with hollow interior because of the expected utilization of noble metals and the high surface area-driven activity. For instance, Yusuke Yusuke Yamauchi’s group  reported a synthesis of PdPt bimetallic dendritic nanocages by a selective chemical etching of Pd cores from dendritic Pt-on-Pd NCs. The hollow interiors and dendritic shells were demonstrated to provide abundant catalytic sites, leading to a very high electrocatalytic activity for methanol oxidation reaction.
Authors: Zelin Chen, Jinfeng Zhang, Yuan Zhang, Yunwei Liu, Xiaopeng Han, Cheng Zhong, Wenbin Hu, and Yida Deng
Keywords: PDNI Alloy, Hollow Nanocrystals, Galvanic Replacement Reaction, Dendritic Shell, Ethanol Oxidation, Formic Acid Oxidation, Electrocatalysts