heterostructures*

We investigate the twist angle dependent interlayer exciton lifetimes in MoSe₂/WSe₂ twisted bilayers (TBLs) capsulated by hexagonal boron nitride (hBN). Three R-stacking style samples with different twist angles are prepared with careful angle alignment and measured by time-resolved photoluminescence at low-temperature. The interlayer exciton lifetimes are found to change significantly with a small change in the twist angle by one order of magnitude. Using a low-energy continuum model, we theoretically explain two possible mechanisms influencing twist angle dependent interlayer exciton radiative lifetimes. The shift to indirect transitions in the momentum space with an increasing twist angle and the energy modulation from the moiré potential both have a significant impact on interlayer exciton lifetimes. We further predict distinct temperature dependence of interlayer exciton lifetimes in TBLs with different twist angles, which is partially validated by experiments.