Phase-Controlled Synthesis of Pd–Se Nanocrystals for Phase-Dependent Oxygen Reduction Catalysis

• Published in: Nano letters Vol. 21; no. 9; pp. 3805 - 3812
• Main Authors: Yu, Zhiyong, Xu, Shulin, Feng, Yonggang, Yang, Chengyong, Yao, Qing, Shao, Qi, Li, Ya-fei, Huang, Xiaoqing
• Format: Journal Article
• Language: English
• Published: United States American Chemical Society 12.05.2021
• Subjects: Oxygen Reduction Reaction; Chalcogenide; Palladium; Phase; Selenium
• ISSN: 1530-6984; 1530-6992; 1530-6992
• DOI: 10.1021/acs.nanolett.1c00147

Searching for highly efficient oxygen reduction reaction (ORR) electrocatalysts for fuel cell technology, in which the crystal structure plays a powerful role in regulating the electrocatalysis, is urgent yet challenging. Herein, we have explored the active and stable Pd–Se alloy electrocatalysts with controlled phase toward alkaline ORR. The phase-controlled Pd–Se nanoparticles (NPs) show interesting phase-dependent electrocatalytic performance, in which the Pd17Se15 NPs/C exhibits much better ORR performance than its counterpart, Pd7Se4 NPs/C, and the commercial Pd/C and Pt/C. Based on the detailed analysis, Pd in Pd17Se15 possesses more Se atom coordination and a higher valence state, thus providing a stronger capacity for the absorption of oxygenated species. DFT further reveals more charge transfer from the Pd17Se15 surface to the *OOH intermediate, which is the reason for the activity enhancement.