17:00 〜 17:15
▲ [16p-B6-14] CuNi binary alloy catalyst for growth of nitrogen-substituted graphene by low pressure chemical vapor deposition
キーワード：graphene, doping, binary alloy
The lack of band gaps in monolayer graphene hinders its use in the diverse fields of electronics and different approaches have been explored to open a band gap. A possibility to open a band gap is to dope graphene sheets with heteroatoms by controlling the electron and hole carrier concentrations, and consequently the Fermi-level. Furthermore, bilayer graphene shows a band gap, and it is wider for N-doped bilayer graphene, depending highly on the content of N atoms.
The synthesis remains difficult due to low solubilities of C and N atoms in Cu substrate, commonly used for monolayer graphene, while Ni substrates have higher solubilities of these elements. In spite of these higher solubilities, Ni substrates does not allow for a predictable segregation at the surface and the controllability for the number of layers is low. The CuNi binary alloy would then possess the suitable controllability of both the number of layers and the N-doping concentration. The synthesis of N-doped bilayer graphene growth is explored on CuNi substrates with melamine as the sole precursor of both C and N atoms.
Raman spectroscopy, atomic force microscopy and transmission electron microscopy analysis confirm the growth of small bilayer and few-layer graphene domains of 100 μm. X-ray photoelectron spectroscopy analysis shows the presence of around 5.8 at% of nitrogen, including pyridine, pyrrolic and graphitic nitrogen. The Fast Fourier Transform (FFT) pattern shows the formation of a twist angle of around 18° in the N-doped bilayer graphene.
The synthesis remains difficult due to low solubilities of C and N atoms in Cu substrate, commonly used for monolayer graphene, while Ni substrates have higher solubilities of these elements. In spite of these higher solubilities, Ni substrates does not allow for a predictable segregation at the surface and the controllability for the number of layers is low. The CuNi binary alloy would then possess the suitable controllability of both the number of layers and the N-doping concentration. The synthesis of N-doped bilayer graphene growth is explored on CuNi substrates with melamine as the sole precursor of both C and N atoms.
Raman spectroscopy, atomic force microscopy and transmission electron microscopy analysis confirm the growth of small bilayer and few-layer graphene domains of 100 μm. X-ray photoelectron spectroscopy analysis shows the presence of around 5.8 at% of nitrogen, including pyridine, pyrrolic and graphitic nitrogen. The Fast Fourier Transform (FFT) pattern shows the formation of a twist angle of around 18° in the N-doped bilayer graphene.