Nucleation of Chromate Conversion Coating on Aluminum 2024‐T3 Investigated by Atomic Force Microscopy

This manuscript propose the operando detection technique of the physical properties change of electrolyte during Li-metal battery operation.The physical properties of electrolyte solution such as viscosity (η) and mass densities (ρ) highly affect the feature of electrochemical Li-metal deposition on the Li-metal electrode surface. Therefore, the operando technique for detection these properties change near the electrode surface is highly needed to investigate the true reaction of Li-metal electrode. Here, this study proved that one of the atomic force microscopy based analysis, energy dissipation analysis of cantilever during force curve motion, was really promising for the direct investigation of that. The solution drag of electrolyte, which is controlled by the physical properties, is directly concern the energy dissipation of cantilever motion. In the experiment, increasing the energy dissipation was really observed during the Li-metal dissolution (discharge) reaction, understanding as the increment of η and ρ of electrolyte via increasing of Li-ion concentration. Further, the dissipation energy change was well synchronized to the charge-discharge reaction of Li-metal electrode.This study is the first report for direct observation of the physical properties change of electrolyte on Li-metal electrode reaction, and proposed technique should be widely interesting to the basic interfacial electrochemistry, fundamental researches of solid-liquid interface, as well as the battery researches.

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Brittle Behaviour in Aspirin Crystals: Evidence of Spalling Fracture

10.26434/chemrxiv.13238708.v1 ◽

2020 ◽

Author(s):

Benjamin P. A. Gabriele ◽

Craig J. Williams ◽

Douglas Stauffer ◽

Brian Derby ◽

Aurora J. Cruz-Cabeza

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Single Crystals ◽

Spalling Fracture ◽

Force Microscopy ◽

Atomic Force ◽

Afm Imaging

<div> <div> <div> <p>Single crystals of aspirin form I were cleaved and indented on their dominant face. Upon inspection, it was possible to observe strongly anisotropic shallow lateral cracks due to the extreme low surface roughness after cleavage. Atomic Force Microscopy (AFM) imaging showed spalling fractures nucleating from the indent corners, forming terraces with a height of one or two interplanar spacings d100. The formation of such spalling fractures in aspirin was rationalised using basic calculations of attachment energies, showing how (100) layers are poorly bonded when compared to their relatively higher intralayer bonding. An attempt at explaining the preferential propagation of these fractures along the [010] direction is discussed. </p> </div> </div> </div>

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Brittle Behaviour in Aspirin Crystals: Evidence of Spalling Fracture

10.26434/chemrxiv.13238708 ◽

2020 ◽

Author(s):

Benjamin P. A. Gabriele ◽

Craig J. Williams ◽

Douglas Stauffer ◽

Brian Derby ◽

Aurora J. Cruz-Cabeza

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Single Crystals ◽

Spalling Fracture ◽

Force Microscopy ◽

Atomic Force ◽

Afm Imaging

<div> <div> <div> <p>Single crystals of aspirin form I were cleaved and indented on their dominant face. Upon inspection, it was possible to observe strongly anisotropic shallow lateral cracks due to the extreme low surface roughness after cleavage. Atomic Force Microscopy (AFM) imaging showed spalling fractures nucleating from the indent corners, forming terraces with a height of one or two interplanar spacings d100. The formation of such spalling fractures in aspirin was rationalised using basic calculations of attachment energies, showing how (100) layers are poorly bonded when compared to their relatively higher intralayer bonding. An attempt at explaining the preferential propagation of these fractures along the [010] direction is discussed. </p> </div> </div> </div>

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