LAUSR.org creates dashboard-style pages of related content for over 1.5 million academic articles. Sign Up to like articles & get recommendations!

Pb arachidate Langmuir-Blodgett coatings of silicon wafers: relation between Pb particle density and subphase composition

Photo by roxannshepard from unsplash

The formation of lead arachidate (Pb(AA)2) coatings produced by Langmuir tensiometry (LT) was studied in dependence of lead nitrate (Pb(NO3)2) concentration in the aqueous subphase at pH 5.5. The stable… Click to show full abstract

The formation of lead arachidate (Pb(AA)2) coatings produced by Langmuir tensiometry (LT) was studied in dependence of lead nitrate (Pb(NO3)2) concentration in the aqueous subphase at pH 5.5. The stable Pb(AA)2 monolayers were transferred to Si wafers and TEM grids at 35 mN/m in the liquid condensed phase of the AA monolayer applying the Langmuir-Blodgett (LB) (ten monolayers) or the Langmuir-Schaefer (LS) technique, respectively. The most homogeneous monolayer was obtained at a Pb(NO3)2 concentration of 0.1 mM by using the LS method. Most homogeneous films (five bilayers) were obtained for a Pb(NO3)2 concentration of 0.01 mM by using the LB method. The formed films are investigated by transmission electron microscopy (monolayer produced by LS), X-ray reflectivity (XRR), and atomic force microscopy (films produced by LB). These methods revealed the formation of homogeneously distributed lead inclusions in the formed monolayers and films. Pb aggregates increase in number whereas their average size stays constant at ≈ 50 nm2 with increasing Pb(NO3)2 concentration. Thickness parameters were determined by XRR. With increasing Pb(NO3)2 concentration, the bilayer thickness was found to increase. Furthermore, the patterns (111) and (200) for a cubic lead structure were found. The experimental results are compared with simulations obtained from geometry optimization on a semi-empirical quantum level to discuss the lead-ion binding to the AA molecules at pH 5.5.

Keywords: no3 concentration; langmuir blodgett; microscopy; arachidate; subphase

Journal Title: Colloid and Polymer Science
Year Published: 2018

Link to full text (if available)


Share on Social Media:                               Sign Up to like & get
recommendations!

Related content

More Information              News              Social Media              Video              Recommended



                Click one of the above tabs to view related content.