AFM measurements of nanofluids/functional groups/mineral substrates systems
Description
The main hypothesis of this work is that silicon dioxide nanofluids can reduce the work of adhesion required to pull aromatic and alkane functional groups from quartz and feldspar mineral substrates. A secondary hypothesis is that the adhesion work is directly related to adhesion force - both of which are measured on AFM. The data collected shows that adhesion force decreases as nanofluid concentration increases up to 0.5 wt% after which it begins to decrease. Mean adhesion force (pN) with error margin was obtained from histograms generated during atomic force microscope (AFM) measurements. The measurements consist of 1024 force curves per test. Standard deviation values are also included. A 2-D plot can reveal the trend of adhesion force with nanofluid concentration. Similarly, a linear relationship seems to exist between adhesion force and adhesion work (aJ), but the latter seems to also depend on scan rate and displacement. Mean adhesion work measurements were obtained in similar manner to force curves. All associated data are available in the spreadsheet named" AFM data" All of the 1,024 force curves obtained per test were carefully analyzed and a single force curve was selected to describe the role of intermolecular forces. As presented in the document "AFM force curves", a plot consists of two portions: approach and retract
Files
Steps to reproduce
Chemical force mapping and imaging of aforementioned rock mineral surfaces were performed using MFP-3D AFM (Asylum Research, Santa Barbara, CA).HNP and NNP nanoparticles size distribution were characterized in air using a Cypher ES AFM (Asylum Research, Santa Barbara, CA). Cantilever spring constants were auto-calibrated in air through thermal tune method (27) and found be 0.111N/m- 0.112N/m.