Long-Range Magnetic Order in Nickel Hydroxide-Functionalized Graphene Quantum Dots.
Lukáš MichalRajarshi RoyDavid HolecI Jénnifer GómezNaděžda PizúrováDavid NečasAnna DolečkováJiřina MedalováPetr LepcioLenka ZajíčkováPublished in: The journal of physical chemistry letters (2022)
In this work, we demonstrate the prospect of chemically synthesizing transition metal (Ni) doped magnetic graphene quantum dots (GQDs) with the sole aim of shedding light on their magnetic properties. Our results show that adsorption of nickel hydroxide on predominantly paramagnetic GQDs reveals antiferromagnetic ordering in the M-T profile around 10 K with change of the spin exchange coupling deviating from J = 1/2 to J = 1, mainly arising from the d-p mixing hybridization between the p orbital of carbon from the GQD and the d orbital of Ni. Furthermore, our results are well complemented by ab initio simulations showing asymmetry of the up and down spins around the Fermi level for nickel hydroxide-doped GQDs with long-range spin polarization. Furthermore, the magnitude of the net magnetic moment generated for doped GQDs on the carbon atoms is found to be site-dependent (surface or edge).
Keyphrases
- quantum dots
- transition metal
- reduced graphene oxide
- molecularly imprinted
- room temperature
- metal organic framework
- sensitive detection
- carbon nanotubes
- aqueous solution
- single molecule
- energy transfer
- gold nanoparticles
- density functional theory
- oxide nanoparticles
- mass spectrometry
- current status
- ionic liquid
- walled carbon nanotubes
- nucleic acid
- african american