Energy dispersive-EXAFS of Pd nucleation at a liquid/liquid interface

16th International Conference on X-ray Absorption Fine Structure

Chang, S.-Y.^1 ; Booth, S.G.^6 ; Uehara, A.^4 ; Mosselmans, J.F.W.^2 ; Cibin, G.^2 ; Pham, V.-T.^5,6 ; Nataf, L.^5 ; Dryfe, R.A.W.^6 ; Schroeder, S.L.M.^1,2,3

School of Chemistry, University of Manchester, Manchester

M13 9PL, United Kingdom^1

Diamond Light Source Ltd., Diamond House, Harwell Science and Innovation Campus, Fermi Ave, Didcot, Oxfordshire

OX11 0DE, United Kingdom^2

School of Chemical and Process Engineering, Faculty of Engineering, University of Leeds, Leeds

LS2 9JT, United Kingdom^3

Division of Nuclear Engineering Science, Research Reactor Institute, Kyoto University, Osaka, Asashironishi, Kumatori

590-0494, Japan^4

Synchrotron SOLEIL, L'Orme des Merisiers, Saint-Aubin, BP48, Gif-sur-Yvette

91192, France^5

Center for Quantum Electronics, Institute of Physics, Vietnam Academy of Science and Technology, P.O. Box 429, Boho, Hanoi

10000, Viet Nam^6

关键词: Equilibrium potentials;    Extended X-ray absorption fine structures;    Interfacial potential;    Liquid/liquid interface;    Nucleation process;    Open circuit potential measurements;    Preliminary analysis;    Tetraethylammonium;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/712/1/012058/pdf
DOI  :  10.1088/1742-6596/712/1/012058

来源: IOP

【 摘 要 】

Energy dispersive extended X-ray absorption fine structure (EDE) has been applied to Pd nanoparticle nucleation at a liquid/liquid interface under control over the interfacial potential and thereby the driving force for nucleation. Preliminary analysis focusing on Pd K edge-step height determination shows that under supersaturated conditions the concentration of Pd near the interface fluctuate over a period of several hours, likely due to the continuous formation and dissolution of sub-critical nuclei. Open circuit potential measurements conducted ex-situ in a liquid/liquid electrochemical cell support this view, showing that the fluctuations in Pd concentration are also visible as variations in potential across the liquid/liquid interface. By decreasing the interfacial potential through inclusion of a common ion (tetraethylammonium, TEA+) the Pd nanoparticle growth rate could be slowed down, resulting in a smooth nucleation process. Eventually, when the TEA+ions reached an equilibrium potential, Pd nucleation and particle growth were inhibited.