As we have shown with both static and time resolved photoluminescence spectroscopy at 77 K, the three materials which form 2D Dion -Jacobson phases all exhibit a broadband emissive component with hundreds of nanometers of bandwidth. Such broad emission, as indicated by the analysis of the power and temperature dependence of the PL, can be attributed to trap-mediated excitonic recombination or STEs. In the case of 1,4-XDA, the strongest emission is not the broad band component, but rather a narrowband, short-lived component characterized by a small Stokes shift, which is consistent with the radiative recombination of free excitons; at room temperature this narrow band feature at 420 nm is the only significant emission.