Selective adsorption of bismuth telluride nanoplatelets through electrostatic attraction

Abstract

We demonstrate a facile technique to assemble solution phase-synthesized bismuth telluride (Bi₂Te₃) nanoplatelets into arrays of micropatterns. Aminosilane self-assembled monolayers (SAMs) are printed on silicon dioxide (SiO₂) substrates using microcontact printing (μCP). The SAM printed surfaces are terminated with amine-groups allowing Bi₂Te₃ nanoplatelet selective adsorption by electrostatic attraction. Using Kelvin probe force microscopy, the electrical potential difference between aminosilane SAM and Bi₂Te₃ nanoplatelet surfaces is found to be ∼650 mV, which is larger than that (∼400 mV) between the SiO₂ substrate and Bi₂Te₃ nanoplatelet surfaces. The selective adsorption provides an opportunity for integrating solution phase-grown topological insulators toward several device-level applications.