Design of innovative procedures for airborne particle collection based on the occupational risk assessment of 2D MXene materials synthetized from MAX phases by high frequency acoustic emission technology

Nanomaterials (NMs) represent a transformative class of materials whose unique ability to combine multiple functionalities makes them essential in advanced technological applications. Among them, MAX phases, a nanolaminate material with the general formula Mₙ₊₁AXₙ, are used as precursors for the synthesis of MXenes, obtained by selectively etching the A-layer. Recent evidence suggests that both MAX phases and MXenes may accumulate in the human body, potentially leading to genotoxicity and cellular dysfunction. This master’s thesis aims to develop a comprehensive assessment of occupational exposure risks to nanomaterials (NMs) during the synthesis of Ti₃C₂ MXenes and MAX phase precursors, based on the development of a protocol for the collection of airborne samples in the nano-scale range. Risk control measures were also proposed to minimize exposure. A tiered approach was implemented to evaluate particle size, composition and concentration. An innovative sampling procedure was developed, employing filters with varying pore sizes and pump flow rates. Morphological and compositional analyses were carried out using Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectroscopy (EDS). The results revealed that workers may be exposed to both incidental and engineered nanomaterials during various stages of the process. Specifically, three stages of MAX phase production generated significantly higher nanoparticle (NP) concentrations compared to background levels, with the highest absolute concentration observed during MXenes synthesis. Based on these findings, potential control measures were proposed according to the hierarchy of control framework to minimize exposure risks.