Dynamic shear force microscopy of confined liquids at a gold electrode

2017 ◽  
Vol 199 ◽  
pp. 299-309 ◽  
Author(s):  
Günther Krämer ◽  
Florian Hausen ◽  
Roland Bennewitz
Keyword(s):  
Shear Force ◽  
Nanometer Scale ◽  
Dynamic Shear ◽  
Surface Charges ◽  
Force Microscopy ◽  
Confined Liquids ◽  
Atomic Force ◽  
Viscous Shear ◽  
Shear Force Microscopy ◽  
Single Crystal Electrode

The confinement of liquids in nanometer-scale gaps can lead to changes in their viscous shear properties. For liquids of polar molecules, the charge state of the confining surfaces has a significant influence on the structure in the confined liquid. Here we report on the implementation of dynamic shear force microscopy in an electrochemical cell. Lateral oscillations of the tip of an atomic force microscope were magnetically activated at a frequency of about 50 kHz. The damping of the lateral tip oscillation was recorded as a function of the tip–sample distance and of the electrode potential at the surface of a Au(100) single crystal electrode. The influence of surface charges on the shear response of the nano-confined liquids was demonstrated for the ionic liquid [EMIM][NTf2] and for aqueous Na2SO4 solution.

Dynamic shear force microscopy of viscosity in nanometer-confined hexadecane layers

2016 ◽  
Vol 28 (13) ◽  
pp. 134004 ◽  
Author(s):  
Marc-Dominik Krass ◽  
Nitya Nand Gosvami ◽  
Robert W Carpick ◽  
Martin H Müser ◽  
Roland Bennewitz
Keyword(s):  
Shear Force ◽  
Dynamic Shear ◽  
Force Microscopy ◽  
Shear Force Microscopy

Nanorheology and boundary slip in confined liquids using atomic force microscopy

2008 ◽  
Vol 20 (31) ◽  
pp. 315201 ◽  
Author(s):  
Abdelhamid Maali ◽  
Bharat Bhushan
Keyword(s):  
Atomic Force Microscopy ◽  
Boundary Slip ◽  
Force Microscopy ◽  
Confined Liquids ◽  
Atomic Force

Microwave Atomic Force Microscopy: Quantitative Measurement and Characterization of Electrical Properties on the Nanometer Scale

2011 ◽  
Vol 5 (1) ◽  
pp. 016602 ◽  
Author(s):  
Lan Zhang ◽  
Yang Ju ◽  
Atsushi Hosoi ◽  
Akifumi Fujimoto
Keyword(s):  
Atomic Force Microscopy ◽  
Electrical Properties ◽  
Quantitative Measurement ◽  
Nanometer Scale ◽  
Force Microscopy ◽  
Atomic Force

Silica Nanoparticles to Polish Tooth Surfaces for Caries Prevention

2008 ◽  
Vol 87 (10) ◽  
pp. 980-983 ◽  
Author(s):  
R.M. Gaikwad ◽  
I. Sokolov
Keyword(s):  
Silica Nanoparticles ◽  
Ex Vivo ◽  
Bacterial Attachment ◽  
Nanometer Scale ◽  
Human Teeth ◽  
Cariogenic Bacteria ◽  
Force Microscopy ◽  
Atomic Force ◽  
Tooth Surfaces ◽  
Scale Roughness

Although silica particles have been used for tooth polishing, polishing with nanosized particles has not been reported. Here we hypothesize that such polishing may protect tooth surfaces against the damage caused by cariogenic bacteria, because the bacteria can be easily removed from such polished surfaces. This was tested on human teeth ex vivo. The roughness of the polished surfaces was measured with atomic force microscopy (AFM). A considerably lower nanometer-scale roughness was obtained when silica nanoparticles were used to polish the tooth surfaces, as compared with conventional polishing pastes. Bacterial attachment to the dental surfaces was studied for Streptococcus mutans, the most abundant cariogenic bacteria. We demonstrated that it is easier to remove bacteria from areas polished with silica nanoparticles. The results demonstrate the advantage of using silica nanoparticles as abrasives for tooth polishing.

Surface displacements and surface charges on Ba2CuWO6 and Ba2Cu0.5Zn0.5WO6 ceramics induced by local electric fields investigated with scanning-probe microscopy

2007 ◽  
Vol 22 (1) ◽  
pp. 193-200
Author(s):  
Ralf-Peter Herber ◽  
Gerold A. Schneider
Keyword(s):  
Electric Fields ◽  
Ferroelectric Properties ◽  
Piezoresponse Force Microscopy ◽  
Ferroelectric Material ◽  
Relaxor Ferroelectrics ◽  
Surface Charges ◽  
Kelvin Probe ◽  
Force Microscopy ◽  
Atomic Force ◽  
Surface Displacements

Ba2CuWO6 (BCW) was first synthesized in the mid 1960s, and it was predicted to be a ferroelectric material with a very high Curie temperature of 1200 °C [N. Venevtsev and A.G. Kapyshev: New ferroelectrics. Proc. Int. Meet. Ferroelectr.1, 261 (1966)]. Since then, crystallographic studies were performed on the compound with the result that its crystal structure is centrosymmetric. Thus for principal reason, BCW cannot be ferroelectric. That obvious contradiction was examined in this study. Disk-shaped ceramic samples of BCW and Ba2Cu0.5Zn0.5WO6 (BCZW) were prepared. Because of the low electrical resistivity of the ceramics, it was not possible to perform a typical polariszation hysteresis loop for characterization of ferroelectric properties. Scanning electron microscopy investigations strongly suggest that the reason for the conductivity is found in the impurities/precipitations within the microstructure of the samples. With atomic force microscopy (AFM) in piezoresponse force microscopy (PFM) mode, it is possible to characterize local piezoelectricity by imaging the ferroelectric domains. Neither BCW nor BCZW showed any domain structure. Nevertheless, when local electric fields were applied to the surfaces of the ceramics topographic displacements, imaged with AFM, and surface charges, imaged with Kelvin probe force microscopy (KFM) and PFM, were measured and remained stable on the surface for the time of the experiment. Therefore BCW and BCZW are considered to be electrets and possibly relaxor ferroelectrics.

Direct manipulation of metallic nanosheets by shear force microscopy

2018 ◽  
Vol 271 (2) ◽  
pp. 222-229 ◽  
Author(s):  
Z. BI ◽  
W. CAI ◽  
Y. WANG ◽  
G. SHANG
Keyword(s):  
Shear Force ◽  
Direct Manipulation ◽  
Force Microscopy ◽  
Shear Force Microscopy
Sign in / Sign up

Export Citation Format

Share Document