TY - JOUR
T1 - Ligand-centered electrochemical processes enable CO2 reduction with a nickel bis(triazapentadienyl) complex
AU - Dubrawski, Zachary
AU - Heidebrecht, Joshua
AU - Puerta Lombardi, Braulio M.
AU - Hyla, Alexander S.
AU - Willkomm, Janina
AU - Radford, Chase L.
AU - Lin, Jian Bin
AU - Welch, Gregory C.
AU - Ponnurangam, Sathish
AU - Roesler, Roland
AU - Prokopchuk, Demyan E.
AU - Piers, Warren E.
N1 - Funding Information:
This research was undertaken thanks in part to funding from the Canada First Research Excellence Fund (CFREF). Computational resources were provided by Compute Canada. The Canada Foundation for Innovation (CFI JELF #34102) is acknowledged for equipment funding.
Publisher Copyright:
© 2019 The Royal Society of Chemistry.
PY - 2019
Y1 - 2019
N2 - We report the synthesis of Ni(TAPPy)2 (TAPPy = 1,3,5-triazapentadienyl-2,4-bis(2-pyridyl)) and its reactivity with CO2 under reducing conditions. Electrochemical reduction of Ni(TAPPy)2 under inert gas reveals that the complex accommodates up to two additional electrons, with DFT calculations indicating that electron density is delocalized almost exclusively onto the TAPPy ligand framework. The singly reduced product [K(crypt)][Ni(TAPPy)2] (crypt = 2.2.2-cryptand) has been synthesized, and its EPR data is consistent with having ligand-based radical anion character. Controlled potential electrolysis experiments reveal that reduced Ni(TAPPy)2 converts CO2 to form CO; however, spectroscopic and computational data indicate that deactivation readily occurs to form Ni(L)(CO)n compounds, CO32-, and carboxylated (RCOO-) ligand decomposition products. This study highlights that redox activity at the ligand can play an important role during the reduction of CO2 using transition metal complexes.
AB - We report the synthesis of Ni(TAPPy)2 (TAPPy = 1,3,5-triazapentadienyl-2,4-bis(2-pyridyl)) and its reactivity with CO2 under reducing conditions. Electrochemical reduction of Ni(TAPPy)2 under inert gas reveals that the complex accommodates up to two additional electrons, with DFT calculations indicating that electron density is delocalized almost exclusively onto the TAPPy ligand framework. The singly reduced product [K(crypt)][Ni(TAPPy)2] (crypt = 2.2.2-cryptand) has been synthesized, and its EPR data is consistent with having ligand-based radical anion character. Controlled potential electrolysis experiments reveal that reduced Ni(TAPPy)2 converts CO2 to form CO; however, spectroscopic and computational data indicate that deactivation readily occurs to form Ni(L)(CO)n compounds, CO32-, and carboxylated (RCOO-) ligand decomposition products. This study highlights that redox activity at the ligand can play an important role during the reduction of CO2 using transition metal complexes.
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U2 - 10.1039/c8se00623g
DO - 10.1039/c8se00623g
M3 - Article
AN - SCOPUS:85065160972
SN - 2398-4902
VL - 3
SP - 1172
EP - 1181
JO - Sustainable Energy and Fuels
JF - Sustainable Energy and Fuels
IS - 5
ER -