A semiconductor Sc 2 S 3 monolayer with ultrahigh carrier mobility for UV blocking filter application.

For humans, ultraviolet (UV) light from sun is harmful to our eyes and eye-related cells. This detrimental fact requires scientists to search for a material that can efficiently absorb UV light while allowing lossless transmission of visible light. Using an unbiased first-principles swarm intelligence structure search, we explored two-dimensional (2D) Sc-S crystals and identified a novel Sc 2 S 3 monolayer with good thermal and dynamical stability. The optoelectronic property simulations revealed that the Sc 2 S 3 monolayer has a wide indirect bandgap (3.05 eV) and possesses an ultrahigh carrier mobility (2.8 × 10 3 cm 2 V -1 s -1 ). Remarkably, it has almost transparent visible light absorption, while it exhibits an ultrahigh absorption coefficient up to × 10 5 cm -1 in the ultraviolet region. Via the application of biaxial strain and thickness modulation, the UV light absorption coefficients of Sc 2 S 3 can be further improved. These findings manifest an attractive UV blocking optoelectronic characteristic of the Sc 2 S 3 configuration as a prototypical nanomaterial for the potential application in UV blocking filters.