Direct Measurement of Adhesion Force of Individual Aerosol Particles by Atomic Force Microscopy

A new method, namely, force–distance curve mapping, was developed to directly measure the adhesion force of individual aerosol particles by atomic force microscopy. The proposed method collects adhesion force from multiple points on a single particle. It also takes into account the spatial distribution of the adhesion force affected by topography (e.g., the variation in the tip angle relative to the surface, as well as the force imposed upon contact), thereby enabling the direct and quantitative measurement of the adhesion force representing each particle. The topographic effect was first evaluated by measuring Polystyrene latex (PSL) standard particles, and the optimized method was then applied on atmospherically relevant model dust particles (quartz, ATD, and CJ-1) and inorganic particles (ammonium sulfate and artificial sea salt) to inter-compare the adhesion forces among different aerosol types. The method was further applied on the actual ambient aerosol particles collected on the western coast of Japan, when the region was under the influence of Asian dust plume. The ambient particles were classified into sea salt (SS), silicate dust, and Ca-rich dust particles based on individual particle analysis (micro-Raman or Scanning Electron Microscope/Energy Dispersive X-ray Spectroscopy (SEM-EDX)). Comparable adhesion forces were obtained from the model and ambient particles for both SS and silicate dust. Although dust particles tended to show smaller adhesion forces, the adhesion force of Ca-rich dust particles was larger than the majority of silicate dust particles and was comparable with the inorganic salt particles. These results highlight that the original chemical composition, as well as the aging process in the atmosphere, can create significant variation in the adhesion force among individual particles. This study demonstrates that force–distance curve mapping can be used as a new tool to quantitatively characterize the physical properties of aerosol particles on an individual basis.

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Adhesion force mapping on wood by atomic force microscopy: influence of surface roughness and tip geometry

Royal Society Open Science ◽

10.1098/rsos.160248 ◽

2016 ◽

Vol 3 (10) ◽

pp. 160248 ◽

Cited By ~ 14

Author(s):

X. Jin ◽

B. Kasal

Keyword(s):

Surface Roughness ◽

Atomic Force Microscopy ◽

Wood Surface ◽

Adhesion Force ◽

Data Interpretation ◽

Natural Fibre ◽

Force Distribution ◽

Adhesion Forces ◽

Force Microscopy ◽

Atomic Force

This study attempts to address the interpretation of atomic force microscopy (AFM) adhesion force measurements conducted on the heterogeneous rough surface of wood and natural fibre materials. The influences of wood surface roughness, tip geometry and wear on the adhesion force distribution are examined by cyclic measurements conducted on wood surface under dry inert conditions. It was found that both the variation of tip and surface roughness of wood can widen the distribution of adhesion forces, which are essential for data interpretation. When a common Si AFM tip with nanometre size is used, the influence of tip wear can be significant. Therefore, control experiments should take the sequence of measurements into consideration, e.g. repeated experiments with used tip. In comparison, colloidal tips provide highly reproducible results. Similar average values but different distributions are shown for the adhesion measured on two major components of wood surface (cell wall and lumen). Evidence supports the hypothesis that the difference of the adhesion force distribution on these two locations was mainly induced by their surface roughness.

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Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM) phase images

Atmospheric Measurement Techniques Discussions ◽

10.5194/amtd-1-1-2008 ◽

2008 ◽

Vol 1 (1) ◽

pp. 1-19

Author(s):

G. Helas ◽

M. O. Andreae

Keyword(s):

Atomic Force Microscopy ◽

Chemical Compound ◽

Aerosol Particles ◽

Dust Particles ◽

Soil Dust ◽

Surface Features ◽

Force Microscopy ◽

Atomic Force ◽

Phase Images ◽

Micro Features

Abstract. We show that atomic force microscopy (AFM) phase images can reveal surface features of soil dust particles, which are not evident using other microscopic methods. The non-contact AFM method is able to resolve topographical structures in the nanometer range as well as to uncover repulsive atomic forces and attractive van der Waals' forces, and thus gives insight to surface properties. Though the method does not allow quantitative assignment in terms of chemical compound description, it clearly shows deposits of distinguishable material on the surface. We apply this technique to dust aerosol particles from the Sahara collected over the Atlantic Ocean and describe micro-features on the surfaces of such particles.

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Surface features on Sahara soil dust particles made visible by atomic force microscope (AFM) phase images

Atmospheric Measurement Techniques ◽

10.5194/amt-1-1-2008 ◽

2008 ◽

Vol 1 (1) ◽

pp. 1-8 ◽

Cited By ~ 7

Author(s):

G. Helas ◽

M. O. Andreae

Keyword(s):

Atomic Force Microscopy ◽

Chemical Compound ◽

Aerosol Particles ◽

Dust Particles ◽

Soil Dust ◽

Surface Features ◽

Force Microscopy ◽

Atomic Force ◽

Phase Images ◽

Micro Features

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Capillary Forces Studied with Atomic Force Microscopy

MRS Proceedings ◽

10.1557/proc-1025-b12-07 ◽

2007 ◽

Vol 1025 ◽

Author(s):

Sahar Maghsoudy-Louyeh ◽

Bernhard R. Tittmann

Keyword(s):

Atomic Force Microscopy ◽

Adhesion Force ◽

Theoretical Calculations ◽

Capillary Forces ◽

Adhesion Forces ◽

Coating Materials ◽

Force Microscopy ◽

Atomic Force ◽

Repulsive Forces ◽

Hydrophilic Materials

AbstractThe deposition of films and coatings is sometimes influenced by the presence of small amounts of moisture, which can affect the nucleation and growth processes. It is important to understand the behavior of coating materials–especially in semiconductors–in terms of hydrophilicity/hydrophobicity along with adhesion forces. Our technical approach centers on the use of the atomic force microscope (AFM) which was found to be a reliable tool for studying the surface characteristics of materials. In addition to obtaining topographic information, the AFM can also probe attractive or repulsive forces between the tip and the sample surfaces. In this research, a systematic study of the influence of humidity on the adhesion forces between different AFM tips (silicon and silicon nitride) and both hydrophilic and hydrophobic materials (quartz, calcite, mica, graphite) has been conducted using atomic force microscopy. Several force-distance curves measured by the M5 AFM have been gathered at a series of different humidity levels and different locations on the samples. In this paper, measurements of the adhesion force for hydrophobic and hydrophilic materials versus humidity are presented. The results show that the adhesion force on graphite which has hydrophobic character is independent of humidity variation. Results also show that the adhesion force for fused quartz, mica, and calcite which are hydrophilic materials, change dramatically with increasing humidity due to capillary forces. This is in good agreement with theoretical calculations.

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Shale adhesion force measurements via atomic force microscopy

Oil & Gas Science and Technology – Revue d’IFP Energies nouvelles ◽

10.2516/ogst/2021057 ◽

2021 ◽

Vol 76 ◽

pp. 73

Author(s):

Nikolai Mitiurev ◽

Michael Verrall ◽

Svetlana Shilobreeva ◽

Alireza Keshavarz ◽

Stefan Iglauer

Keyword(s):

Atomic Force Microscopy ◽

Adhesion Force ◽

Force Measurement ◽

Sample Surface ◽

Wettability Alteration ◽

Rock Surface ◽

United States Bureau ◽

Adhesion Forces ◽

Force Microscopy ◽

Atomic Force

Wettability of sedimentary rock surface is an essential parameter that defines oil recovery and production rates of a reservoir. The discovery of wettability alteration in reservoirs, as well as complications that occur in analysis of heterogeneous sample, such as shale, for instance, have prompted scientists to look for the methods of wettability assessment at nanoscale. At the same time, bulk techniques, which are commonly applied, such as USBM (United States Bureau of Mines) or Amott tests, are not sensitive enough in cases with mixed wettability of rocks as they provide average wettability values of a core plug. Atomic Force Microscopy (AFM) has been identified as one of the methods that allow for measurement of adhesion forces between cantilever and sample surface in an exact location at nanoscale. These adhesion forces can be used to estimate wettability locally. Current research, however, shows that the correlation is not trivial. Moreover, adhesion force measurement via AFM has not been used extensively in studies with geological samples yet. In this study, the adhesion force values of the cantilever tip interaction with quartz inclusion on the shale sample surface, have been measured using the AFM technique. The adhesion force measured in this particular case was equal to the capillary force of water meniscus, formed between the sample surface and the cantilever tip. Experiments were conducted with a SiconG cantilever with (tip radius of 5 nm). The adhesion forces between quartz grain and cantilever tip were equal to 56.5 ± 5 nN. Assuming the surface of interaction to be half spherical, the adhesion force per area was 0.36 ± 0.03 nN/nm2. These measurements and results acquired at nano-scale will thus create a path towards much higher accuracy-wettability measurements and consequently better reservoir-scale predictions and improved underground operations.

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