The high efficiency of energy transfer is consistent with our previous expectation that the in-situ grown QDs are adsorbed or in contact with the surface. It is therefore not surprising that the in-situ case has much higher QE than the mixed case given the distance between donor and acceptor. What is surprising, however, is that the number density of QDs is very low while still reaching near unity transfer. This suggests that there must be long-range exciton transport for nearly every exciton to reach a QD. Even the small-toaveraged sized NPLs represent a ~1000-2500 nm 2 area that the exciton must sample before reaching a QD, and this must outpace the recombination rate. We therefore became interested in exploring the exciton diffusion through modeling to better understand transport within these NPLs.