Tip Charge Dependence of Three-Dimensional AFM Mapping of Concentrated Ionic Solutions

[EN] A molecular scale understanding of the organization and structure of a liquid near a solid surface is currently a major challenge in surface science. It has implications across different fields from electrochemistry and energy storage to molecular biology. Three-dimensional AFM generates atomic...

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Detalles Bibliográficos
Autores: Benaglia, Simone, Uhlig, Manuel R., Hernández-Muñoz, Jose, Chacón, Enrique, Tarazona, Pedro, García García, Ricardo
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:España
Institución:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/257627
Acceso en línea:http://hdl.handle.net/10261/257627
Access Level:acceso abierto
Palabra clave:Interface thermodynamics
Surface thermodynamics
Descripción
Sumario:[EN] A molecular scale understanding of the organization and structure of a liquid near a solid surface is currently a major challenge in surface science. It has implications across different fields from electrochemistry and energy storage to molecular biology. Three-dimensional AFM generates atomically resolved maps of solid-liquid interfaces. The imaging mechanism behind those maps is under debate, in particular, for concentrated ionic solutions. Theory predicts that the observed contrast should depend on the tip’s charged state. Here, by using neutrally, negatively, and positively charged tips, we demonstrate that the 3D maps depend on the tip’s polarization. A neutral tip will explore the total particle density distribution (water and ions) while a charged tip will reveal the charge density distribution. The experimental data reproduce the key findings of the theory.