Abstract
Detailed in operando studies of electrochemically induced PbBrF deposition at the liquid mercury/liquid electrolyte interface are presented. The nucleation and growth were monitored using time-resolved X-ray diffraction and reflectivity combined with electrochemical measurements, revealing a complex potential-dependent behavior. PbBrF deposition commences at potentials above -0.7 V with the rapid formation of an ultrathin adlayer of one unit cell thickness, on top of which (001)-oriented three-dimensional crystallites are formed. Two potential regimes are identified. At low overpotentials, slow growth of a low surface density film of large crystals is observed. At high overpotentials, crossover to a potential-independent morphology occurs, consisting of a compact PbBrF deposit with a saturation thickness of 25 nm, which forms within a few minutes. This potential behavior can be rationalized by the increasing supersaturation near the interface, caused by the potential-dependent Pb2+ deamalgamation, which changes from a slow reaction-controlled process to a fast transport-controlled process in this range of overpotentials. In addition, growth on the liquid substrate is found to involve complex micromechanical effects, such as crystal reorientation and film breakup during dissolution.
| Original language | English |
|---|---|
| Pages (from-to) | 10905-10915 |
| Number of pages | 11 |
| Journal | Langmuir |
| Volume | 36 |
| Issue number | 37 |
| DOIs | |
| State | Published - 22 Sep 2020 |
Bibliographical note
Publisher Copyright:Copyright © 2020 American Chemical Society.
Funding
The authors acknowledge financial support by the DFG through project MA 1618/18 and funding for LISA by the BMBF through project K16FK1/K19FK2. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at PETRA III, and we would like to thank Oliver Seeck, Uta Rütt, and Rene Kirchhof for assistance in using P08 and Milena Lippmann for assistance in using the PETRA III chemistry laboratory. This research was supported by the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704. The authors acknowledge financial support by the DFG through project MA 1618/18 and funding for LISA by the BMBF through project K16FK1/K19FK2. We acknowledge DESY (Hamburg, Germany), a member of the Helmholtz Association HGF, for the provision of experimental facilities. Parts of this research were carried out at PETRA III, and we would like to thank Oliver Seeck, Uta Ru?tt, and Rene Kirchhof for assistance in using P08 and Milena Lippmann for assistance in using the PETRA III chemistry laboratory. This research was supported by the National Synchrotron Light Source II, a U.S. Department of Energy (DOE) Office of Science User Facility operated for the DOE Office of Science by Brookhaven National Laboratory under Contract No. DE-SC0012704.
| Funders | Funder number |
|---|---|
| National Synchrotron Light Source II | |
| U.S. Department of Energy | |
| Office of Science | |
| Brookhaven National Laboratory | DE-SC0012704 |
| Deutsche Forschungsgemeinschaft | MA 1618/18 |
| Bundesministerium für Bildung und Forschung | K16FK1/K19FK2 |
| Helmholtz Association |