A Dynamically Stabilized Single-Nickel Electrocatalyst for Selective Reduction of Oxygen to Hydrogen Peroxide.
Chemistry
; 24(64): 17011-17018, 2018 Nov 16.
Article
in En
| MEDLINE
| ID: mdl-30277283
ABSTRACT
On-location electrochemical generation of H2 O2 is of great current interest. Herein, selective two-electron reduction of O2 to H2 O2 by a single [NiII (H2 O)6 ]2+ cation that is dynamically associated with a negatively charged metal-organic layer (MOL) by hydrogen bonding and coulombic interactions is reported. In contrast, NiII centers covalently immobilized on the MOL reduce O2 to H2 O in a four- electron process. Oxygen adsorption by [NiII (H2 O)6 ]2+ followed by two-electron reduction generates neutral [NiII (H2 O)4 (OH)(OOH)]0 , which momentarily disconnects from the negatively charged MOL to avoid the injection of additional electrons. Release of H2 O2 from [NiII (H2 O)4 (OH)(OOH)]0 regenerates [NiII (H2 O)6 ]2+ , which regains affinity to the MOL. Such dynamically associated NiII single-metal electrocatalysts ensure high selectivity and represent a new strategy for generating selective catalysts for electrochemical production of important chemicals.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Chemistry
Journal subject:
QUIMICA
Year:
2018
Type:
Article