@gkhmadsen.bsky.social

Theoretical materials chemistry at TU Wien

Linus' work on identifying uncertain motifs for active learning of rough copper–water interface MLIP out in ACS Materials Au @pubs.acs.org pubs.acs.org/doi/10.1021/... Funded by @fwf-at.bsky.social through COE-MECS

How Realistic Are Idealized Copper Surfaces? A Machine Learning Study of Rough Copper–Water Interfaces

Copper is a highly promising catalyst for the electrochemical CO2 reduction reaction (CO2RR) since it is the only pure metal that can form highly added-value products such as ethylene and ethanol. Since the CO2RR takes place in aqueous solution, the detailed atomic structure of the water–copper interface is essential for unraveling the key reaction mechanisms. In this study, we investigate copper–water interfaces exhibiting nanometer-scale roughnesses. We introduce two molecular dynamics protocols to create rough copper surfaces, which are subsequently brought into contact with water. From these interfaces, we sample additional training configurations from machine-learning-interatomic-potential-driven molecular dynamics simulations containing hundreds of thousands of atoms. An active learning workflow is developed to identify regions with high spatially resolved uncertainty and convert them into DFT-feasible cells through a modified amorphous matrix embedding approach. Finally, we analyze the local environments at the interface using unsupervised machine-learning techniques. Unique environments emerge on the rough copper surfaces absent from model systems, including stacking-fault-induced configurations and undercoordinated corner atoms. Notably, corner atoms consistently feature chemisorbed water molecules in our simulations, indicating their potential importance in catalytic processes.

pubs.acs.org

Happy #QuantumDay to all who celebrate! Max Planck submitted work on blackbody radiation to the German Physical Society #OTD in 1900. His novel “quantum hypothesis” suggested that matter emits and absorbs light with frequency f only in discrete chunks of energy E=hf. 🧪 ⚛️ (1/n) Image: AIP

A black and white photo of Max Planck. His arms are crossed and he is looking at the camera. Planck has a substantial mustache and his hair is receding. He is wearing a heavy, dark suit with a high-collared white shirt and a small black bowtie.