Seed‐Initiated Synthesis and Tunable Doping Graphene for High‐Performance Photodetectors

Abstract

Due to the promising utilizations in nanoelectronics, doping‐tunable graphene is paid extensive attentions. Nevertheless, a harmless approach to dope/co‐dope graphene in a controllable and easy way with low cost is still unattainable. Herein, through seeding of 0D N & S dual‐doped graphene quantum dots (N & S dual‐doped GQDs) on a catalytic substrate and then dynamic chemical vapor deposition (CVD), a monolayered dual‐doped graphene film is demonstrated. The concentrations of dopants in graphene are strictly discerned in accordance with preliminary seeding for dual‐doped GQDs. Through the monitoring of growing process, the research elucidates the growth mechanism of the graphene, and unveils that dual‐doped GQDs can serve as the nucleation centers for creating doped‐graphene films by 2D epitaxial growth and thus graphene with designed dopant concentration can be obtained. Finally, the photodetector built on N & S dual‐doped graphene film is found to perform satisfactorily, accompanying high detectivity (≈1.42 × 1010 cm Hz1/2 W−1) and responsivity (61 mA W−1), at wavelength of 1550 nm. The research proposes a dexterous approach for synthesizing tunably doped graphene films by the combination of locally controlled nucleation seeds and in situ CVD, which lays the foundation for applying graphene in industries of photonic and electronic devices.

2D Graphene in Interface Engineering of 3D Graphene‐Based Thermal Management

“…The typical characteristic bands of 3D‐Gr that are the D ‐band (1350 cm −1 ), G ‐band (1580 cm −1 ), and 2 D ‐band (2700 cm −1 ) appear. [ 14,15 ] The distinct D ‐band existing in all samples can be attributed to the abundantly exposed edges of nanosized 3D‐Gr. In addition, all samples exhibit a shoulder peak around at 1620 cm −1 , which is named as D ′‐band.…”

Heteroatom Codoped Graphene: The Importance of Nitrogen

“…Despite the fact that sulfur does not fit in the graphene plane and bulges out of the sheet, the most studied codoped graphene system is sulfur and nitrogen codoped graphene. There are so many articles published about this system − …”

“…Efficient photocatalytic H 2 O 2 production was achieved since the codoped graphene induced a better light absorption and promoted a more significant charge migration . Sulfur and nitrogen codoped graphene nanomaterials have broad visible absorption , and superb luminescence properties. − They can be used in bioimaging. , Also, they were reported to have a fluorescence quantum yield 9.3 times higher than that of undoped graphene. Thus, they are promising materials for developing light-emitting devices …”

Theory study on catalytic hydrogenation of CO2 to formic acid over Si, N‐doped modified graphene quantum dots supported single atom Fe

“…And it has been shown that doping Si on carbon‐based materials will change the catalyst surface electron arrangement or surface acidity or alkalinity, thus affecting the catalytic performance [12, 39, 40]. In this work, catalyst models of Fe‐loaded on pure graphene quantum dots [41, 42] (Fe‐C 4 ) and Fe‐loaded on N‐doped modified graphene quantum dots (Fe‐N 4 ) and Fe‐loaded on Si‐doped modified graphene quantum dots (Fe‐Si 4 ) were constructed. The adsorption properties of CO 2 on Fe‐C 4 and Fe‐N 4 and Fe‐Si 4 and the reaction mechanisms of CO 2 hydrogenation to formic acid over these three catalysts were investigated using DFT calculations.…”