On the role of hydrogen bond acceptors in electrocatalytic hydride formation
Year: 2024
Type: article
Abstract: Carefully designed mechanistic studies often provide the most important insights for future advances in catalysis. Here, we study the role of hydrogen-bond (H-bond)-accepting functional groups in a catalyst microenvironment. This approach provides quantitative information on the rate of electrochemically driven catalyst-hydride formation from protons. Ligand substitution of Na(diglyme) 2 [Fe 4 N(CO) 12 ] was used to access a series of six clusters with various H-bond-accepting secondary coordination sphere (SCS) functional groups that were chosen to span a wide range of H-bond-acceptor strengths ( B ). We demonstrate that the rate of formation of [H-Fe 4 N(CO) 12 ] − increases linearly with B , because the H-bond acceptor modulates the reactivity of water that serves as a proton source for the formation of [H-Fe 4 N(CO) 12 ] − . Specifically, the substrate water likely accumulates near the catalyst active site and/or has lower p K a when the SCS functional groups are stronger H-bond acceptors. The rate of [H-Fe 4 N(CO) 12 ] − formation is not correlated directly with p K a of the SCS H-bond-accepting functional group.
Source: Cell Reports Physical Science
Institution: University of California, Davis
Language: English
Field: Energy
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $5,460
Award: G6521850827
OpenAlex ID: W4404994089