Hydrogen generation from weak acids: electrochemical and computational studies of a diiron hydrogenase mimic.
Extended investigation of electrocatalytic generation of dihydrogen using [(mu-1,2-benzenedithiolato)][Fe(CO)3]2 has revealed that weak acids, such as acetic acid, can be used. The catalytic reduction producing dihydrogen occurs at approximately -2 V for several carboxylic acids and phenols resulting in overpotentials of only -0.44 to -0.71 V depending on the weak acid used. This unusual catalytic reduction occurs at a potential at which the starting material, in the absence of a proton source, does not show a reduction peak. The mechanism for this process and structures for the intermediates have been discerned by electrochemical and computational analysis. These studies reveal that the catalyst is the monoanion of the starting material and an ECEC mechanism occurs.
Felton
Greg A N
GA
Department of Chemistry, The University of Arizona, Tucson, Arizona 85721, USA.
Vannucci
Aaron K
AK
Chen
Jinzhu
J
Lockett
L Tori
LT
Okumura
Noriko
N
Petro
Benjamin J
BJ
Zakai
Uzma I
UI
Evans
Dennis H
DH
Glass
Richard S
RS
Lichtenberger
Dennis L
DL
D000143:Acids / Q000737:chemistry*; D040761:Biomimetic Materials / Q000737:chemistry* / Q000378:metabolism*; D002384:Catalysis; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D006859:Hydrogen / Q000737:chemistry*; D006864:Hydrogenase / Q000378:metabolism*; D007506:Iron-Sulfur Proteins / Q000378:metabolism*; D008958:Models, Molecular; D008968:Molecular Conformation; D013055:Spectrophotometry, Infrared
D000143:Acids; D007506:Iron-Sulfur Proteins; D006859:Hydrogen; C118830:iron hydrogenase; D006864:Hydrogenase