Ligand Decomposition Differences during Thermal Sintering of Oleylamine-Capped Gold Nanoparticles in Ambient and Inert Environments: Implications for Conductive Inks.

Gold nanoparticles (GNPs) are essential in creating conductive inks vital for advancing printable electronics, sensing technologies, catalysis, and plasmonics. A crucial step in fabricating useful GNP-based devices is understanding the thermal sintering process and particularly the decomposition pathways of ligands in different environments. This study addresses a gap in the existing research by examining the sintering of oleylamine (OA)-capped GNPs in both ambient (air) and inert (N) environments. Through a series of analyses including TGA/MS, Raman spectroscopy, and XPS, distinctive OA decomposition behaviors were identified in air and nitrogen environments. The research delineates two OA decomposition pathways resulting in different porosity, microstructure, and electrical conductivity of GNP films sintered in air and nitrogen environments. The study offers some insights that can steer the sintering and utilization of the GNP sintering process and promises to aid the future development of nanoparticle-based printable electronics.