Investigating the Trimethylaluminium/Water ALD Process on Mesoporous Silica by In Situ Gravimetric Monitoring

Investigating the Trimethylaluminium/Water ALD Process on Mesoporous Silica by In Situ Gravimetric Monitoring

Blog Article

A low amount of AlOx was successfully deposited on an unordered, mesoporous SiO2 powder using 1–3 ALD (Atomic Layer Deposition) cycles of trimethylaluminium and water.The process was realized in a self-built ALD china glaze beaches and toes setup featuring a microbalanceand a fixed particle bed.The reactor temperature was varied between 75, 120, and 200 °C.

The self-limiting nature of the deposition was verified by in situ gravimetric monitoring for all temperatures.The coated material was further analyzed by nitrogen sorption, inductively coupled plasma-optical emission spectroscopy, powder X-ray diffraction, high-resolution transmission electron microscopy, attenuated total reflection Fourier transformed infrared spectroscopy, and elemental analysis.The obtained mass gains correspond to average growth between 0.

81–1.10 Å/cycle depending on substrate temperature.In addition, the different mass gains during the half-cycles in combination with the analyzed aluminum content after one, two, and three cycles indicate a change in the preferred surface reaction of the trimethylaluminium molecule from a predominately two-ligand exchange with hydroxyl groups to more single-ligand exchange with increasing cycle number.

Nitrogen sorption isotherms demonstrate (1) homogeneously coated mesopores, (2) a decrease in surface area, and (3) rock cliff reservoir a reduction of the pore size.The experiment is successfully repeated in a scale-up using a ten times higher substrate batch size.