Sol–Gel Application for Consolidating Stone: An Example of Project-Based Learning in a Physical Chemistry Lab

Abstract

A Project Based Learning (PBL) methodology was used in the practical laboratories of the Advanced Physical Chemistry department. The project type proposed simulates “real research” focusing on sol–gel synthesis and the application of the obtained sol as a stone consolidant. Students were divided into small groups (2 to 3 students) to simulate a real-world research team. This procedure allowed students to explore the sol–gel transition from synthesis until dry gel (xerogel), and analyze the properties of the sol, gel, and xerogels (especially pore volume and pore size). Moreover, the students learned an example of an application of sol–gel materials (as a “stone consolidant”) and were introduced to the use of several instrumental techniques such as nitrogen adsorption, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), mercury intrusion porosimetry (MIP), and rheology measurement.