Computational and Experimental Evaluation of the Functionalization Reaction of Si(100) with Aniline and Pyridine

• Benjamin Sanhueza, Chemistry, Universidad Técnica Federico Santa María
• Cecilia Bustamante, Chemistry, Universidad Técnica Federico Santa María

• Andrew Teplyakov, Department of Chemistry and Biochemistry, University of Delaware
• Tania Sandoval, Department of Chemical and Environmental engineer, Universidad Técnica Federico Santa María

In recent decades, the exponential growth in surface modification to control the physicochemical properties of materials has become a central focus in nanotechnology. This has generated the need to precisely characterize and control these molecular systems and to explore new surface functionalizations that improve device performance and reduce manufacturing costs. Devices such as the ones based on semiconductors, self-assembled monolayers, solar cells, transistors, and others requiring atomic-scale control from these advancements. This study focuses on surface functionalization for the potential growth of metal-organic frameworks (SURMOFs) used for contaminant detection. These structures, with their large surface area, can effectively interact with contaminants within their voids, requiring precise control. Utilizing functionalized surfaces allows for the creation of selective growth patterns, improving diffusion and increasing the contact area for optical detection.

This work investigates a novel functionalization of Si(100) surface with hydroxyl and hydrogen terminations by aniline and pyridine . Computational methods based on density functional theory (DFT) were employed to define and strengthen the modes of interaction between the organic molecules and silicon (100). The experimental investigation of reacting these molecules with a surface was carried out, and the atomic composition of the surface and adsorbate coverage were characterized using techniques such as X-ray photoelectron spectroscopy (XPS), and atomic force microscopy (AFM) was used to evaluate surface roughness and structural changes. These approach allowed for the estimation of adsorption energies and core-level binding energies, providing a deeper understanding of the interaction mechanisms. This controlled and well-characterized functionalization could enhance the effectiveness of SURMOFs detectors and open new possibilities for applications in other fields that require precisely modified surfaces.