Direct Comparison of the Performance of a Bio-inspired Synthetic Nickel Catalyst and a [NiFe]-Hydrogenase, Both Covalently Attached to Electrodes

Journal Article · Mon Oct 12 04:00:00 EDT 2015 · Angewandte Chemie International Edition (Online)

DOI:https://doi.org/10.1002/anie.201502364· OSTI ID:1243266

Rodriguez-Macia, Patricia; Dutta, Arnab; Lubitz, Wolfgang; Shaw, Wendy J.; Rudiger, Olaf

The active site of hydrogenases has been a source of inspiration for the development of molecular catalysts. However, direct comparisons between molecular catalysts and enzymes have not been possible because different techniques are used to evaluate both types of catalysts, minimizing our ability to determine how far we’ve come in mimicking the impressive enzymatic performance. Here we directly compare the catalytic properties of the [Ni(PCy2NGly2)2]2+ complex with the [NiFe]-hydrogenase from Desulfobivrio vulgaris Miyazaki F (DvMF) immobilized to a functionalized electrode under identical conditions. At pH=7, the enzyme has higher performance in both activity and overpotential, and is more stable, while at low pH, the molecular catalyst outperforms the enzyme in all respects. The Ni complex also has increased tolerance to CO. This is the first direct comparison of enzymes and molecular complexes, enabling a unique understanding of the benefits and detriments of both systems, and advancing our understanding of the utilization of these bioinspired complexes in fuel cells. AD and WJS acknowledge the Office of Science Early Career Research Program through the US Department of Energy (US DOE), Office of Science, Office of Basic Energy Sciences (BES), and Pacific Northwest National Laboratory (PNNL). PNNL is operated by Battelle for the US DOE.

• Research Organization: Pacific Northwest National Laboratory (PNNL), Richland, WA (US)
• Sponsoring Organization: USDOE
• DOE Contract Number: AC05-76RL01830
• OSTI ID: 1243266
• Report Number(s): PNNL-SA-108491; KC0302010
• Journal Information: Angewandte Chemie International Edition (Online), Journal Name: Angewandte Chemie International Edition (Online) Journal Issue: 42 Vol. 24; ISSN 1521-3773
• Publisher: Gesselschaft Deutscher Chemiker
• Country of Publication: United States
• Language: English