Surface functionalisation of porous silicon using 3-Aminopropyl triethoxy silane (APTS)

Abstract

Porous silicon (p-Si) has emerged as a versatile material with immense potential in biomedical, optical, and sensor applications due to its high surface area and tunable surface chemistry. However, to fully exploit its capabilities, surface modification is essential to enhance its chemical stability and functional performance. This study focuses on the surface functionalisation of p-Si using 3-Aminopropyltriethoxysilane (APTS), a silane coupling agent known for introducing amine functionalities onto silicon-based surfaces. The process involves the hydrolysis and condensation of APTS molecules, forming covalent Si–O–Si bonds with the p-Si surface, resulting in a stable organosilane layer. The presence of terminal amine groups facilitates further conjugation with biomolecules or nanostructures, broadening the applicability of p-Si in areas such as biosensing, drug delivery, and nanoelectronics. The study also explores the characterization techniques employed—such as FTIR, contact angle measurements, and SEM/AFM imaging—to confirm successful functionalisation and understand the morphology and surface chemistry alterations. The findings demonstrate that APTS treatment is an effective strategy for enhancing the functional versatility of porous silicon surfaces.

Keywords:- Porous Silicon (p-Si), Surface Functionalisation, Aminopropyltriethoxysilane (APTS), Silanization, Amine Functional Groups, Covalent Bonding, Biosensors, Surface Characterization, Nanotechnology, Biomedical Applications