Intense, stable and excitation wavelength-independent photoluminescence emission in the blue-violet region from phosphorene quantum dots

Abstract

Nanoscale phosphorene quantum dots (PQDs) with few-layer structures were fabricated by pulsed laser ablation of a bulk black phosphorus target in diethyl ether. An intense and stable photoluminescence (PL) emission of the PQDs in the blue-violet wavelength region is clearly observed for the first time, which is attributed to electronic transitions from the lowest unoccupied molecular orbital (LUMO) to the highest occupied molecular orbital (HOMO) and occupied molecular orbitals below the HOMO (H-1, H-2), respectively. Surprisingly, the PL emission peak positions of the PQDs are not red-shifted with progressively longer excitation wavelengths, which is in contrast to the cases of graphene and molybdenum disulphide quantum dots. This excitation wavelength-independence is derived from the saturated passivation on the periphery and surfaces of the PQDs by large numbers of electron-donating functional groups which cause the electron density on the PQDs to be dramatically increased and the band gap to be insensitive to the quantum size effect in the PQDs. This work suggests that PQDs with intense, stable and excitation wavelength-independent PL emission in the blue-violet region have a potential application as semiconductor-based blue-violet light irradiation sources.

Dose- and Time-Dependent Cytotoxicity of Layered Black Phosphorus in Fibroblastic Cells

“…A noticeable peak was observed near 1000 cm −1 , attributed to the stretching vibrations of P–O [ 23 ]. The peaks found near 1140 and 1620 cm −1 represented the P=O stretching modes of layered BP [ 23 , 24 ]. On the other hand, broad absorption bands were observed, ranging from 2400 cm −1 to 3500 cm −1 , which could be attributed to the CO 2 stretching and OH stretching vibrations due to exposure of the layered BP to ambient atmosphere.…”

Recent progress in 2D group-VA semiconductors: from theory to experiment

“…Additionally, Ge et al pointed out that the intense and stable PL peaks of the black phosphorene quantum dots have been found in the blue-violet wavelength region. 327 Due to the excellent PL intensity, stability and its excitation wavelengthindependence in the blue-violet light region, phosphorene is expected to be a suitable material for blueviolet light irradiation sources. Aghaeimeibodi et al reported a new class of near-infrared emission from defect states in phosphorene.…”

A batch-by-batch free route for the continuous production of black phosphorus nanosheets for targeted combination cancer therapy

“…2b) of the synthesized BP NSs support the co-existence of BP (2p) and Au (4f)-Sn (3d), and the apparent color of the synthesized NSs was black. This implies that Au-Sn successfully induced the conversion of RP into BP, and did not significantly perturb the original BP structure 24 . These results were consistent with 3D and 2D AFM images on mica substrates (Fig.…”