posted on 2023-01-05, 15:13authored byŞener Özönder, Caner Ünlü, Cihat Güleryüz, Levent Trabzon
We report on time-dependent
density functional theory calculations
of the excited states of 63 different graphene quantum dots (GQDs)
in square shape with side lengths of 1, 1.5, and 2 nm. We investigate
the systematics and trends in the UV–vis absorption spectra
of these GQDs, which are doped with elements B, N, O, S, and P at
dopant percentages of 1.5%, 3%, 5%, and 7%. The results show how the
peaks in the UV and visible parts of the spectrum as well as the total
absorption evolve in the chemical parameter space along the coordinates
of size, dopant type, and dopant percentage. The absorption spectra
calculated here can be used to obtain particular GQD mixture proportions
that would yield a desired absorption profile such as flat absorption
across the whole visible spectrum or one that is locally peaked around
a chosen wavelength.