Electrocatalytic properties, X-ray crystallographic studies, and infrared spectroelectrochemistry (IR-SEC) of Mn(bpy-tBu)(CO)3Br and [Mn(bpy-tBu)(CO)3(MeCN)](OTf) are reported. Addition of Brönsted acids to CO2-saturated solutions of these Mn complexes and subsequent reduction of the complexes lead to the stable and efficient production of CO from CO2. Unlike the analogous Re catalysts, these Mn catalysts require the addition of Brönsted acids for catalytic turnover.
View Article and Find Full Text PDFThe effective design of an artificial photosynthetic system entails the optimization of several important interactions. Herein we report stopped-flow UV-visible (UV-vis) spectroscopy, X-ray crystallographic, density functional theory (DFT), and electrochemical kinetic studies of the Re(bipy-tBu)(CO)(3)(L) catalyst for the reduction of CO(2) to CO. A remarkable selectivity for CO(2) over H(+) was observed by stopped-flow UV-vis spectroscopy of [Re(bipy-tBu)(CO)(3)](-1).
View Article and Find Full Text PDFThe light-assisted co-generation of carbon monoxide and hydrogen from carbon dioxide and water is reported. The combination of a homogeneous CO-evolving electrocatalyst and a heterogeneous H(2)-evolving photoelectrode surface provides for tunability of the H(2)/CO ratio. A total Faradaic efficiency of 102 ± 5% and a H(2)/CO ratio of 2:1 were achieved at a low homogeneous catalyst concentration (0.
View Article and Find Full Text PDFFive Re(bipy)(CO)(3)Cl complexes were prepared and studied where bipy was 4,4'-dicarboxyl-2,2'-bipyridine (1), 2,2'-bipyridine (2), 4,4'-dimethyl-2,2'-bipyridine (3), 4,4'-di-tert-butyl-2,2'-bipyridine (4), and 4,4'-dimethoxy-2,2'-bipyridine (5). From this group, a significantly improved catalyst, Re(bipy-tBu)(CO)(3)Cl (4), for the reduction of carbon dioxide to carbon monoxide was found. The complex shows two one-electron reductions under argon, one reversible at -1445 mV (vs SCE), and one irreversible at -1830 mV.
View Article and Find Full Text PDFResearch in the field of catalytic reduction of carbon dioxide to liquid fuels has grown rapidly in the past few decades. This is due to the increasing amount of carbon dioxide in the atmosphere and a steady climb in global fuel demand. This tutorial review will present much of the significant work that has been done in the field of electrocatalytic and homogeneous reduction of carbon dioxide over the past three decades.
View Article and Find Full Text PDFBridge-flipped' isomers may be defined as pairs of molecules related by a reversal of a bridge of atoms connecting two major parts of the individual molecules. This kind of isomerism is commonly found among benzylideneanilines and phenylhydrazones. Isostructural pairs might be suitable for co-crystallization and are thus useful in the preparation of new solid materials.
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