TY - JOUR

T1 - Preparation of high surface area Cu-Au bimetallic nanostructured materials by co-electrodeposition in a deep eutectic solvent

AU - Plaza-Mayoral, Elena

AU - Sebastián-Pascual, Paula

AU - Dalby, Kim Nicole

AU - Jensen, Kim Degn

AU - Chorkendorff, Ib

AU - Falsig, Hanne

AU - Escudero-Escribano, María

N1 - Funding Information: MEE gratefully acknowledge the Villum Foundation for financial support through a Villum Young Investigator Grant (project number: 19142). This work was also supported by the Danish Foundation through the DFF-Research Project1 (Thematic Research, green transition) grant with number: 0217-00213A ; and the DFF-grant Project 1 with number 9041-00224B . We acknowledge support from the Danish National Research Foundation Center for High Entropy Alloy Catalysis (CHEAC, DNRF-149). We also acknowledge Prof. Elvira Gómez from University of Barcelona who provided valuable experimental discussions. Publisher Copyright: © 2021 The Authors

PY - 2021/12/1

Y1 - 2021/12/1

N2 - Our sustainable future requires finding new, affordable and green routes to prepare nanostructured materials used in renewable energy conversion. In this work we present an electrodeposition method in a deep eutectic solvent (DES) to prepare bimetallic high surface area nanostructures of Cu and Au with tunable structure and composition. The metal electrodeposition performed in choline chloride within a urea deep eutectic solvent allows us to tailor the size, morphology and elemental composition of the deposits. We combine electrochemical methods with scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS) to characterize the electrodeposited nanostructured materials. We assess the increase of the electroactive surface area through the analysis of the lead underpotential deposition (UPD) on the prepared films. Integrated Pb UPD charge values of ca. 1600–4000 μC/cm2 for the prepared Cu-Au films have been calculated, suggesting a 5–14 fold increase of the active surface area compared to flat surfaces of polycrystalline Cu or Au. Our work reports a versatile and environmentally friendly route for the electrodeposition of Cu-Au bimetallic nanostructures in a DES. The combination of a tailored morphology and composition with the high active surface area of the nanostructured materials show that electrodeposition in DES is promising for the development of multimetallic electrocatalysts.

AB - Our sustainable future requires finding new, affordable and green routes to prepare nanostructured materials used in renewable energy conversion. In this work we present an electrodeposition method in a deep eutectic solvent (DES) to prepare bimetallic high surface area nanostructures of Cu and Au with tunable structure and composition. The metal electrodeposition performed in choline chloride within a urea deep eutectic solvent allows us to tailor the size, morphology and elemental composition of the deposits. We combine electrochemical methods with scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and energy dispersive X-ray spectroscopy (EDS) to characterize the electrodeposited nanostructured materials. We assess the increase of the electroactive surface area through the analysis of the lead underpotential deposition (UPD) on the prepared films. Integrated Pb UPD charge values of ca. 1600–4000 μC/cm2 for the prepared Cu-Au films have been calculated, suggesting a 5–14 fold increase of the active surface area compared to flat surfaces of polycrystalline Cu or Au. Our work reports a versatile and environmentally friendly route for the electrodeposition of Cu-Au bimetallic nanostructures in a DES. The combination of a tailored morphology and composition with the high active surface area of the nanostructured materials show that electrodeposition in DES is promising for the development of multimetallic electrocatalysts.

KW - Active surface area

KW - Bimetallic electrodes

KW - Deep eutectic solvent

KW - Electrodeposition

KW - Green solvents

KW - Nanostructured materials

KW - Surface nanostructuring

U2 - 10.1016/j.electacta.2021.139309

DO - 10.1016/j.electacta.2021.139309

M3 - Journal article

AN - SCOPUS:85118099390

VL - 398

JO - Electrochimica Acta

JF - Electrochimica Acta

SN - 0013-4686

M1 - 139309

ER -