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Title: Activating the oxygen electrocatalytic activity of layer-structured Ca 0.5 CoO 2 nanofibers by iron doping
The development of low-cost, highly efficient and stable electrocatalysts for the oxygen evolution reaction (OER) is of great significance for many promising energy storage and conversion applications, including metal–air batteries and water splitting technology. Here we report a layer-structured Ca 0.5 CoO 2 nanofibers composed of interconnected ultrathin nanoplates, synthesized using an electrospinning process. The OER activity of Ca 0.5 CoO 2 can be dramatically improved by iron doping, and the overpotential of Ca 0.5 Co 1− x Fe x O 2 ( x = 0.25) is only 346 mV at a current density of 10 mA cm −2 . The mass activity and intrinsic activity of Ca 0.5 Co 0.75 Fe 0.25 O 2 at 1.6 V are, respectively, ∼18.7 and ∼11.4 times higher than those of Ca 0.5 CoO 2 . Iron doping modifies the electronic structure of Ca 0.5 CoO 2 , resulting in partial oxidation of the surface cobalt and increased amount of highly oxidative species (O 2 2− /O 2 ). Consequently, Ca 0.5 Co 0.75 Fe 0.25 O 2 nanofibers with tuned electronic states have shown great potential as cost-effective and efficient electrocatalysts for OER.  more » « less
Award ID(s):
1742828
PAR ID:
10334422
Author(s) / Creator(s):
; ; ; ;
Date Published:
Journal Name:
Dalton Transactions
Volume:
51
Issue:
9
ISSN:
1477-9226
Page Range / eLocation ID:
3636 to 3641
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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