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Title: Nanoscale Design of Pd-Based Electrocatalysts for Oxygen Reduction Reaction Enhancement in Alkaline Media

Journal Article · · Small Structures

Palladium (Pd)-based electrocatalysts have recently emerged as one class of the foremost promising candidates for the oxygen reduction reaction (ORR) in alkaline media due to their excellent ORR activity and durability and lower costs compared with platinum. Insightful design of Pd-based nano-architectures with optimized active surface sites and maximal intrinsic performance is central to promoting the ORR applications. To further accelerate the sluggish ORR kinetics at the cathode of fuel cells and substantially decrease the overall cost of the electrocatalysts, various strategies, including controlled sizes and shapes with selected crystallographic facets, crystal-phase engineering, heteroatom doping, tailored surface strains, and surface engineering by de-alloying, have been extensively developed in the past decade. Here in this review, a brief introduction to the fundamental ORR mechanisms of Pd-based electrocatalysts in alkaline media is presented, followed by a thorough discussion on various strategies for delicately designing high-performance Pd-based catalysts with corresponding examples. Thereafter, the perspectives and new insights into the challenges are outlined, and some emerging research directions related to the rational design and controlled synthesis of Pd-based ORR electrocatalysts are also proposed.

Research Organization:
Cornell University, Ithaca, NY (United States); State University of New York (SUNY), Binghamton, NY (United States)
Sponsoring Organization:
USDOE Office of Science (SC), Basic Energy Sciences (BES); National Science Foundation (NSF)
Grant/Contract Number:
SC0019445
OSTI ID:
1976413
Journal Information:
Small Structures, Journal Name: Small Structures Journal Issue: 2 Vol. 3; ISSN 2688-4062
Publisher:
WileyCopyright Statement
Country of Publication:
United States
Language:
English

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