Interlaced Pd-Ag nanowires rich in grain boundary defects for boosting oxygen reduction electrocatalysis

• Published in: Nanoscale Vol. 12; no. 9; pp. 5368 - 5373
• Main Authors: Liu, Xiao-Jing, Yin, Xing, Sun, Yi-Dan, Yu, Feng-Jiao, Gao, Xiang-Wen, Fu, Li-Jun, Wu, Yu-Ping, Chen, Yu-Hui
• Format: Journal Article
• Language: English
• Published: England Royal Society of Chemistry 05.03.2020
• Subjects: Catalysts; Crystal defects; Diameters; Electrocatalysts; Grain boundaries; Nanowires; Oxygen reduction reactions; Palladium; Platinum; Silver; Stability tests; Surface defects
• ISSN: 2040-3364; 2040-3372; 2040-3372
• DOI: 10.1039/d0nr00046a

Given the high cost and poisoning issues of Pt, developing Pd-based catalysts as substitutes is highly essential. Although substantial progress has been made, the synthesis of Pd-based electrocatalysts with both high activity and stability in the oxygen reduction reaction (ORR) remains a challenge. In this work, we prepared Pd-Ag nanowires with up to micro-sized length and a diameter of ∼17 nm via a facile modified polyol method. The obtained Pd-Ag nanowires (NWs) exhibit interlaced features and are rich in grain boundary defects. Due to the continuous grain boundaries in the one-dimensional (1D) structure and the optimized composition, the synthesized Pd 1 Ag 1 NWs show half-wave potential of 0.897 V and mass activity of 0.103 A mg −1 in alkaline media toward ORR, higher than those of both state-of-the-art Pt/C and other Pd-Ag counterparts. Significantly, after stability tests over 5000 cycles, Pd 1 Ag 1 NWs shows a 2 mV positive shift, much better than that of Pt/C, exhibiting striking stability for ORR. This work may provide an avenue to construct advanced catalysts by surface defect engineering. Pd-Ag interlaced nanowires with grain boundary defect engineering exhibit enhanced activity and superior stability for oxygen reduction reaction in alkaline media.