Modern energy challenges have amplified interest in transition metal-based molecular electrocatalysts for fuel-forming reactions. The activity of these homogeneous electrocatalysts, and the mechanisms by which they operate, can be uncovered using state-of-the-art electrochemical methods. Catalyst performance can be benchmarked according to metrics obtainable from cyclic voltammograms by analysis of catalytic plateau currents and peak potentials, as well as by foot-of-the-wave analysis. The application of complementary spectroscopic techniques, including spectroelectrochemistry, stopped-flow rapid mixing and transient absorption, are also discussed. In this Review, we present case studies highlighting the utility of these analytical methods in the context of renewable energy. Alongside these examples is a discussion of the theoretical underpinnings of each method, outlining the conditions necessary for the analysis to be rigorous and the type of information that can then be extracted.
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This work was supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences under Award DE-SC0015303. J.L.D. acknowledges support from a Packard Fellowship for Science and Engineering and the Alfred P. Sloan Foundation.
The authors declare no competing interests.
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Lee, K., Elgrishi, N., Kandemir, B. et al. Electrochemical and spectroscopic methods for evaluating molecular electrocatalysts. Nat Rev Chem 1, 0039 (2017). https://doi.org/10.1038/s41570-017-0039
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