Effect of molecular desorption on the electronic properties of self-assembled polarizable molecular monolayers

Gunuk Wang; Hyunhak Jeong; Jamin Ku; Seok-In Na; Hungu Kang; Eisuke Ito; Yun Hee Jang; Jaegeun Noh; Takhee Lee

doi:10.1016/j.jcis.2013.12.052

Effect of molecular desorption on the electronic properties of self-assembled polarizable molecular monolayers

J Colloid Interface Sci. 2014 Apr 1:419:39-45. doi: 10.1016/j.jcis.2013.12.052. Epub 2013 Dec 27.

Authors

Gunuk Wang¹, Hyunhak Jeong², Jamin Ku³, Seok-In Na⁴, Hungu Kang⁵, Eisuke Ito⁶, Yun Hee Jang³, Jaegeun Noh⁷, Takhee Lee⁸

Affiliations

¹ Department of Chemistry and the Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, TX 77005, USA; School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea.
² Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea.
³ School of Materials Science and Engineering, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea.
⁴ School of Flexible and Printable Electronics, Chonbuk National University, Jeonju-si, Jeollabuk-do 561-756, Republic of Korea.
⁵ Department of Chemistry, Hanyang University, Seoul 133-791, Republic of Korea.
⁶ Flucto-Order Functions Research Team, RIKEN-HYU Collaboration Center, RIKEN, 2-1 Hirosawa, Wako, Saitama 351-0198, Japan.
⁷ Department of Chemistry, Hanyang University, Seoul 133-791, Republic of Korea. Electronic address: [email protected].
⁸ Department of Physics and Astronomy, Seoul National University, Seoul 151-747, Republic of Korea. Electronic address: [email protected].

PMID: 24491327
DOI: 10.1016/j.jcis.2013.12.052

Abstract

We investigated the interfacial electronic properties of self-assembled monolayers (SAM)-modified Au metal surface at elevated temperatures. We observed that the work functions of the Au metal surfaces modified with SAMs changed differently under elevated-temperature conditions based on the type of SAMs categorized by three different features based on chemical anchoring group, molecular backbone structure, and the direction of the dipole moment. The temperature-dependent work function of the SAM-modified Au metal could be explained in terms of the molecular binding energy and the thermal stability of the SAMs, which were investigated with thermal desorption spectroscopic measurements and were explained with molecular modeling. Our study will aid in understanding the electronic properties at the interface between SAMs and metals in organic electronic devices if an annealing treatment is applied.

Keywords: Dipole moment; Self-assembled monolayer; Thermal desorption; Work function.