Air-Stable Wafer-Scale Ferromagnetic Metallo-Carbon Nitride Monolayer

Area of Science:

• Materials Science
• Condensed Matter Physics
• Nanotechnology

Background:

• Achieving robust, long-range magnetic ordering in two-dimensional (2D) materials is crucial for technological advancements but faces challenges from quantum/thermal fluctuations and instability.
• Existing 2D magnetic materials like transition metal chalcogenides and metal halides are often air-unstable, while stable 2D carbon-based materials struggle with high magnetic moment density and ordering.

Purpose of the Study:

• To report a novel wafer-scale synthesis of an air-stable metallo-carbon nitride monolayer (MCN) with ultradense single magnetic atoms.
• To demonstrate robust room-temperature ferromagnetism in these MCN materials.
• To explore their potential for electronic and spintronic applications.

Main Methods:

• Wafer-scale synthesis of MCN monolayers (MN4/CN) using low-pressure chemical vapor deposition.
• Thermal dehydrogenation and polymerization of metal phthalocyanine (MPc) on copper foil at elevated temperatures.
• Electronic structure calculations to analyze magnetic exchange coupling.

Main Results:

• Successful synthesis of air-stable MCN monolayers (M=Fe, Co, Ni) with high density of single magnetic atoms.
• Observation of robust room-temperature ferromagnetism and anomalous Hall effects.
• Electronic structure calculations revealed spin-split d-bands near the Fermi level, facilitating long-range ferromagnetic coupling.

Conclusions:

• A novel synthesis approach for wafer-scale MCN monolayers with robust room-temperature ferromagnetism has been demonstrated.
• These materials exhibit excellent chemical stability and potential for practical electronic and spintronic applications.
• The findings pave the way for developing next-generation magnetic 2D materials.