Ab initio structure and capacitance of the metal-water double layer · revision history

Revision 2

Accepted · core change · record

Changes against revision 1:

Title
Ab initio structure and capacitance of the metal-water double layer
Plain
The double layer is a few water molecules thick but its structure sets the voltage felt by reacting molecules. Simulations cannot yet reproduce its measured ability to store charge.
Precise · changed · core
Revision 1: For Pt(111) and Au(111) in dilute aqueous perchlorate or fluoride electrolyte at 300 K, compute from first principles the potential of zero charge, the water orientation profile and the differential capacitance $C(\phi)$ as a function of electrode potential $\phi$, including the capacitance maximum near the potential of zero charge measured on Pt(111) and the Gouy-Chapman minimum at the potential of zero charge measured on Au(111) in dilute electrolyte. An answer is a simulation at fixed electrode potential that reproduces the measured potential of zero charge within $3.3e-4\ \mathrm{statvolt}$ and $C(\phi)$ within 20 percent.
Revision 2: For Pt(111) and Au(111) in dilute aqueous perchlorate or fluoride electrolyte at 300 K, compute from first principles the potential of zero charge, the water orientation profile and the differential capacitance $C(\phi)$ as a function of electrode potential $\phi$, including the capacitance maximum near the potential of zero charge measured on Pt(111) and the Gouy-Chapman minimum at the potential of zero charge measured on Au(111) in dilute electrolyte. An answer is a simulation at fixed electrode potential that reproduces the measured potential of zero charge within $3.3 \times 10^{-4}\ \mathrm{statvolt}$ and $C(\phi)$ within 20 percent.
Settled by
Grand-canonical ab initio molecular dynamics with explicit electrolyte compared with impedance and surface X-ray and vibrational data.
Kind
well-posed
Answer type
value
References
(empty)
Literature status
open
Status note
(empty)
Posed since
(empty)

Decisions