TEXTURAL CHARACTERIZATION OF SILICON QUANTUM DOTS USING BRUNAUER-EMMET-TELLER (BET) ANALYSIS

This study investigates the surface properties, adsorption-desorption characteristics, and pore structures of two samples, Rice Husk Ash (RHA) silica and Silicon Quantum Dots (RSi), to evaluate their potential applications in adsorption and catalysis. The BET surface area analysis reveals that RSi has a significantly higher surface area (365.20 m²/g) compared to RHA (212.35 m²/g), suggesting a greater capacity for adsorption processes. However, the Langmuir surface area for RSi is considerably lower (52.24 m²/g), indicating the presence of a highly porous structure with less monolayer adsorption potential compared to RHA (150.22 m²/g). Both samples exhibit similar micro pore areas, but RSi shows a slightly higher external surface area, indicating a more complex pore structure.Adsorption-desorption analysis reveals that both RHA and RSi have nearly identical adsorption and desorption areas, with RSi showing a marginally better performance. However, when it comes to adsorption and desorption volumes, RSi demonstrates better desorption efficiency (0.52 m³/g) compared to RHA (0.45 m³/g), which retains more adsorbates within its pores.The pore size analysis shows that RHA has larger average pore sizes and exhibits slight pore expansion during desorption, with BJH desorption average pore width reaching 30.55 Å, compared to RSi's more consistent and smaller pore sizes, which remain stable during adsorption and desorption (around 24.22 - 24.54 Å). Therefore, RSi's higher surface area and stable pore structure make it a better candidate for applications requiring consistent pore size and efficient adsorption-desorption processes, while RHA's larger pore sizes and desorption characteristics might be more suitable for applications involving larger molecules or where pore expansion during desorption is beneficial.