Graphene quantum dots assisted synthesis of highconcentration nitrogen doped graphene for infrared photodetectors

The application of graphene in the field of microelectronics is becoming more and more urgent with the emergence of bottlenecks in silicon-based semiconductor technology, and the ability of controllable doping in graphene is, therefore, strongly demanded to tune their electronic or optoelectronic properties for the fabrication of high-performance devices. Herein, through seeding zero-dimensional (0D) nitrogen doped graphene quantum dots (N-GQDs) on a catalytic substrate, the graphene monolayer with nitrogen doping is obtained via chemical vapor deposition (CVD). X-ray photoelectron spectroscopy (XPS) characterization shows the doping concentration reaches up to 32%. Experimental and theoretical investigations reveal that N-GQDs act as the nucleation sites for the epitaxial growth of doped graphene monolayers. Finally, infrared photodetector built on N doped graphene (NG) film is fabricated, accompanying with high detectivity (~1.52 × 10¹⁰ cm Hz^1/2 W⁻¹) and responsivity (79 mA W⁻¹) at the wavelength of 1550 nm. Our study may provide a controllable and convenient approach to achieve doped graphene, which paves the way for the application of graphene in the field of microelectronics.