The present disclosure describes luminescent solar concentrators that include photoluminescent nanoparticles. The photoluminescent nanoparticles include a semiconductor nanocrystal that sensitizes the luminescence of a defect. The defect can include, for example, an atom, a cluster of atoms, or a lattice vacancy. The defect can be incorporated into the semiconductor nanocrystal, adsorbed onto, or otherwise associated with the surface of the semiconductor nanocrystal.