Electrocatalytic reduction of CO₂ to CO and HCO₂⁻ with Zn(ii) complexes displaying cooperative ligand reduction

Abstract

Air-stable zinc(II) pyridyl phosphine complexes, [Zn(2-2,6-{Ph2PNMe}2(NC5H3)Br2] (1) [Zn(2-2-{Ph2PNMe}(NC5H3)Br2] (2) are reported and 1 was capable of electrocatalytic reduction of CO2 at -2.3 V vs. Fc+/0 to yield CO/HCO2H in mixed...

Electrocatalytic Reduction of CO2 and H2O with Zn(II) Complexes Through Metal‐Ligand Cooperation

“…Complex 2 is related to 1 by the replacement of the NMe moieties with NH groups. [36] The characterization of 2 through spectroscopic and single crystal diffraction methods compared well with 1. For example, the 1 H NMR spectrum of compound 2 was similar to that of 1 with the expected absence of the NÀ Me resonance.…”

“…The results for the DFT optimization of [Zn(2,6-{Ph 2 PNMe} 2 (NC 5 H 3 ))Br 2 ] (1) have been previously reported. [36] An analogous approach was taken with [Zn(2,6-{Ph 2 PNH} 2 (NC 5 H 3 ))Br 2 ] (2) with optimization using the B3LYP functional, the def2TZVP basis set, and the polarized continuum model for solvation using acetonitrile. The absence of imaginary values in the frequency analysis confirmed that the resulting structure was a minimum.…”

Electrocatalytic Nitrite Reduction in Neutral Water with Ni(II) and Co(II) Macrocycle Complexes: Catalytic Evaluation and Mechanistic Elucidation

“…The lowest occupied molecular orbital (LUMO, MO88) was composed of a π * orbital of the bis(imino)pyridine portion of the ligand. This ligand‐based MO provides a means for the ligand to act as an electron reservoir for electrocatalysis [41] …”

“…This ligandbased MO provides a means for the ligand to act as an electron reservoir for electrocatalysis. [41] Computational optimization on both single and double reduction products (reductions at À 0.89 V and À 1.05 V) of 1 were also completed and the resulting structures and frontier orbitals are shown in Figures S23-S24. Isosurface plots for these species display similar features and vary only slightly in terms of MO contributions.…”

Recent insights on the use of modified Zn-based catalysts in eCO2RR

“…The electrocatalytic reduction of CO 2 to yield CO and HCO 2 − is a key process in the utilization of CO 2 as a C 1 source for further the synthesis of as a fuel. Air-stable Zn( ii ) pyridyl phosphine complexes, [Zn(κ 2 -2,6-{Ph 2 PNMe} 2 (NC 5 H 3 ))Br 2 ] and [Zn(κ 2 -2-{Ph 2 PNMe}(NC 5 H 3 ))Br 2 ] were reported in a paper by Berro et al , 243 and these were capable of the electrocatalytic reduction of CO 2 at −2.3 V vs. Fc +/0 to yield CO/HCO 2 H in mixed water/acetonitrile solutions. Their reactivity was attributed to a synergy between a reduced, basic ligand and the acidity of the Zn( ii ) center.…”