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Room temperature wideband tunable photoluminescence of pulsed thermally annealed layered black phosphorus



Sara A. Alodan, Justin Gorham, Frank W. DelRio, Fadhel Alsaffar, Ghadeer Aljalham, Chongwu Zhou, Moh R. Amer


Newly explored two-dimensional (2D) materials have shown promising optical properties, owning to the tunable band gap of the layered material with its thickness. A widely used method to achieve tunable light emission (or photoluminescence) is through thickness modulation, but this can only cover specific wavelengths. This approach limits the development of tunable optical devices with high spectral resolution over a wide range of wavelengths. Here, we report wideband tunable light emission of exfoliated black phosphorus nanosheets via pulsed-thermal annealing process in ambient conditions. Tunable anisotropic emission was observed between wavelengths of 590 nm and 720 nm with a spectral resolution of 5 nm. This emission can be maintained for at least 11 days when proper passivation coupled with adequate storage are applied. Using hyperspectral imaging X-ray photoelectron spectroscopy (i-XPS), this tunable emission is found to be strongly dependent on the level of oxidation. We finally discuss the underlying mechanism responsible for the observed tunable emission and show that tunable emission is only observed in nanosheets with thicknesses of (70 nm-125 nm)±10 nm with the maximum range achieved for nanosheets with thicknesses of 125 nm±10 nm. Our results shed some light on an emerging class of 2D oxides with potential in optoelectronic applications.


tunable light emission, black phosphorus photoluminescence, black phosphorus oxide, tunable band gap, annealing, exfoliated black phosphorus


Alodan, S. , Gorham, J. , DelRio, F. , Alsaffar, F. , Aljalham, G. , Zhou, C. and Amer, M. (2020), Room temperature wideband tunable photoluminescence of pulsed thermally annealed layered black phosphorus, Nanophotonics, [online],, (Accessed April 17, 2024)
Created September 20, 2020, Updated October 12, 2021