Revisiting the Electrified Pt(111)/Water Interfaces through an Affordable Double-Reference ab-initio Approach

TL;DR

This study introduces an affordable grand canonical DFT approach combining implicit and explicit solvation models to accurately simulate electrified platinum-water interfaces, providing insights into atomic configurations and electrochemical properties relevant to renewable energy applications.

Contribution

The paper presents a novel, cost-effective GC-DFT method that accurately models electrified solid-liquid interfaces, improving understanding of atomic-scale interfacial phenomena.

Findings

Calculated double layer capacitances match experimental data.

Applied bias significantly alters atomic configurations at the interface.

Water molecule orientation is crucial for accurate PZC and capacitance predictions.

Abstract

The electrified solid-liquid interface plays an essential role in many renewable energy-related applications, including hydrogen production and utilization. Limitations in computational modelling of the electrified solid-liquid interface have held back the understanding of its properties at the atomic-scale level. In this study, we applied the grand canonical density functional theory (GC-DFT) combined with a hybrid implicit/explicit solvation model to reinvestigate the widely studied electrified platinum-water interface affordably. The calculated double layer capacitances of the Pt(111)-water interface over the applied bias potential closely match the experimental and previous theoretical data from expensive ab-initio molecular dynamics simulations. The structural analysis of the interface models reveals that the applied bias potential can significantly affect the Pt(111)-water atomic interface configurations. The orientation of the water molecules next to the Pt(111) surface is vital for correctly describing the potential of zero charge (PZC) and capacitance. Additionally, the GC-DFT results confirm that the absorption of the hydrogen atom under applied bias potential can significantly affect the electrified interfacial properties. The presented affordable GC-DFT approach, therefore, offers an efficient and accurate means to enhance the understanding of electrified solid-liquid interfaces.