Electrocatalytic Water Oxidation by a Copper(II) Complex of an Oxidation-Resistant Ligand

Abstract

The copper­(II) complex Cu­(pyalk)2 (pyalk = 2-pyridyl-2-propanoate) is a robust homogeneous water-oxidation electrocatalyst under basic conditions (pH > 10.4). Water oxidation occurs at a relatively low overpotential for copper of 520–580 mV with a turnover frequency of ∼0.7 s–1. Controlled potential electrolysis experiments over 12 h at 1.1 V vs NHE resulted in the formation of >30 catalytic turnovers of O2 with only ∼20% catalyst degradation. The robustness of the catalyst under fairly harsh conditions and the low overpotential further highlight the oxidation resistance and strong donor character of pyalk.

Quantum Chemical Study of the Mechanism of Water Oxidation Catalyzed by a Heterotrinuclear Ru2Mn Complex

“…23 Vv ersus the standard hydrogen electrode) and is both thermodynamically and kinetically very unfavorable. [38][39][40] Recently,the Llobet group disclosed the synthesisofaheterotrinuclear Ru 2 Mn complex A 0 {[Ru II (tpy)] 2 (m-[Mn II (bpp) 2 ]) (OAc) 2 } 2 + [tpy = 2,2':6',2''-terpyridine, bpp = 3,5-bis(2-pyridyl)pyrazolate]. [1][2][3][4][5] During the past few decades, extraordinary efforts have been dedicated to the synthesis of manganese-based molecular complexes to mimic the structure and function of the OEC.…”

Half‐sandwich Ir (III) and Rh (III) complexes as catalysts for water oxidation with double‐site

“…According to the previous research, the plausible catalytic mechanism for bimetallic complexes is shown in Figure . Firstly, two chlorine atoms which linked to the transition metal center were displaced by molecules of H 2 O.…”

N,N,O Pincer Ligand with a Deprotonatable Site That Promotes Redox‐Leveling, High Mn Oxidation States, and a Mn2O2 Dimer Competent for Catalytic Oxygen Evolution

“…With these bio‐inspired principles in mind, we report a new di‐µ‐oxo dimanganese complex of the pincer 2‐([2,2′‐bipyridin]‐6‐yl)propan‐2‐ol (bipyalkH), which acts as a strong π‐donor upon deprotonation of the alcohol. This ligand incorporates the pyridine alkoxide “pyalk” motif that we previously showed can stabilize high oxidation states in Rh and Ir and promote water‐oxidation catalysis, both with chemical oxidants and electrochemically, with Ir and Cu . We also have previously reported oxygen evolution from our low‐valent precatalyst Mn(bipyalkH)Cl 2 ( 1 , shown in Figure ) driven by KHSO 5 with retention of activity for > 160 h in unbuffered solutions.…”