Kinetics of Hydride Transfer from Metal-Free Hydride Donors to CO2

30 November 2020, Version 1
This content is a preprint and has not undergone peer review at the time of posting.


Selective reduction of CO2 to formate represents an ongoing challenge in photoelectrocatalysis. To provide mechanistic insights, we investigate the kinetics of hydride transfer (HT) from a series of metal-free hydride donors to CO2. The observed dependence of experimental and calculated HT barriers on the thermodynamic driving force was modeled using the Marcus hydride transfer formalism to obtain the insights into the effect of reorganization energies on the reaction kinetics. Our results indicate that, even if the most ideal hydride donor were discovered, the HT to CO2 would exhibit sluggish kinetics (less than 100 turnovers at 0.1 eV driving force), indicating that the conventional HT may not be an appropriate mechanism for Solar conversion of CO2 to formate. We propose that the conventional HT mechanism should not be considered for CO2 reduction catalysis and argue that the orthogonal HT mechanism, previously proposed to address thermodynamic limitations of this reaction, may also lead to lower kinetic barriers for CO2 reduction to formate.


CO2 reduction
Hydride transafer
Product selectivity

Supplementary materials

Supporting Information Kinetics of Hydride transfer from Metal-Free hydrides Donors to CO2


Comments are not moderated before they are posted, but they can be removed by the site moderators if they are found to be in contravention of our Commenting Policy [opens in a new tab] - please read this policy before you post. Comments should be used for scholarly discussion of the content in question. You can find more information about how to use the commenting feature here [opens in a new tab] .
This site is protected by reCAPTCHA and the Google Privacy Policy [opens in a new tab] and Terms of Service [opens in a new tab] apply.