Metal Oxide Heterostructure Array via Spatially Controlled-Growth within Block Copolymer Templates

Area of Science:

• Materials Science
• Nanotechnology
• Chemical Engineering

Background:

• Advanced nanofabrication requires precise 3D control over chemical composition.
• Block copolymer (BCP) self-assembly offers ordered nanostructures.
• Sequential Infiltration Synthesis (SIS) allows material infiltration into BCPs.

Purpose of the Study:

• To present a novel method for fabricating 3D heterostructure nanorod arrays.
• To achieve spatially controlled growth of multiple metal oxides within BCP templates.
• To demonstrate 3D control over chemical composition in nanostructures.

Main Methods:

• Utilizing block copolymer (BCP) templates, specifically polystyrene-block-poly methyl methacrylate.
• Employing sequential infiltration synthesis (SIS) for selective metal oxide growth.
• Tuning precursor diffusion to control the placement of AlOₓ and ZnO within BCP domains.

Main Results:

• Successfully fabricated AlOₓ-ZnO heterostructure nanorod arrays.
• Demonstrated selective growth of different metal oxides within BCP cylindrical domains.
• Verified the 3D structure and composition using STEM tomography and EDX tomography.

Conclusions:

• The presented strategy enables the fabrication of complex 3D nanostructures with controlled chemical composition.
• This approach offers new pathways for advanced materials design and nanofabrication.
• Spatially controlled SIS in BCPs is a powerful tool for creating heterostructures.