A Carbon Electrode Functionalized by a Tricopper Cluster Complex: Overcoming Overpotential and Production of Hydrogen Peroxide in the Oxygen Reduction Reaction. Issue 14 (28th February 2018)

• Record Type: Journal Article
• Authors: Thiyagarajan, Natarajan; Janmanchi, Damodar; Tsai, Yi‐Fang; Wanna, Wondemagegn Hailemichael; Ramu, Ravirala; Chan, Sunney I.; Zen, Jyh‐Myng; Yu, Steve S.‐F.
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 14(2018)
• Page Start: 3612
• Page End: 3616
• Publication Date: 2018-02-28
• Subjects: carbon electrodes -- cluster complexes -- copper -- overpotential -- oxygen reduction reaction; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201712226
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: A study of the oxygen reduction reaction (ORR) on a screen printed carbon electrode surface mediated by the tricopper cluster complex Cu3 (7‐ N ‐Etppz(CH2 OH)) dispersed on electrochemically reduced carbon black, where 7‐ N ‐Etppz(CH2 OH) is the ligand 3, 3′‐(6‐(hydroxymethyl)‐1, 4‐diazepane‐1, 4‐diyl)bis(1‐(4‐ethyl piperazin‐1‐yl)propan‐2‐ol), is described. Onset oxygen reduction potentials of about 0.92 V and about 0.77 V are observed at pH 13 and pH 7 vs. the reversible hydrogen electrode, which are comparable to the best values reported for any synthetic copper complex. Based on half‐wave potentials ( E 1/2 ), the corresponding overpotentials are about 0.42 V and about 0.68 V, respectively. Kinetic studies indicate that the trinuclear copper catalyst can accomplish the 4 e − reduction of O2 efficiently and the ORR is accompanied by the production of only small amounts of H2 O2 . The involvement of the copper triad in the O2 activation process is also verified. Abstract : Involvement of a synthetic copper triad in binding and reduction of O2 is demonstrated. The presence of the third Cu ion is crucial to supplying the third reducing equivalent for O−O bond cleavage and reduces the overpotential.