Ordered mesoporous silica films with pores oriented perpendicular to a titanium nitride substrate

Area of Science:

• Materials Science
• Electrochemistry
• Nanotechnology

Background:

• Mesoporous silica films are crucial for various applications, including sensors and catalysis.
• Titanium nitride (TiN) offers a unique surface for film growth due to its properties.
• Controlling pore structure and orientation is key to optimizing film performance.

Purpose of the Study:

• To demonstrate two novel methods for producing thin mesoporous silica films.
• To achieve pores oriented perpendicular to a titanium nitride surface.
• To explore methods for tuning film properties like pore size and thickness.

Main Methods:

• Stöber silica solution growth with surfactant ordering at the electrode surface.
• Electrochemically assisted growth from an acidic sol via electrode polarization.
• Variation of pore size using different surfactants and swelling agents.

Main Results:

• Successful production of thin mesoporous silica films with small (2-3 nm) pores.
• Demonstrated perpendicular pore orientation relative to the titanium nitride substrate.
• Contrasted film properties (thickness, pore order, pore size) achieved by the two methods.

Conclusions:

• Both demonstrated methods enable controlled growth of mesoporous silica films on TiN.
• TiN surfaces provide an extended electrochemical window for applications with non-aqueous electrolytes.
• These films show promise for nanowire growth and advanced sensor development.