The study of the steady-state and time resolved photoluminescence of 2H-MoS₂:Cl₂ and 2H-WS₂:Br₂ crystals is presented. For both investigated materials two distinct spectral regions was identified: the excitonic region, located in the vicinity of the indirect band gap and consisting of several sharp zero-phonon lines and their phonon replica, and the vibronic broad band IR region, characteristic also for natural crystals without halogen impurities. The thermal quenching of the exciton emission at T>60K was also observed. The strong sharp photoluminescence line of the indirect band gap semiconductors is attributed to the recombination of excitons bound on electron-attractive neutral centers, formed due to the intercalation of the halogen molecules in the van der Waals gap of the layered compound. In the framework of a kinetic model for a compensated semiconductor in thermal equilibrium, the temperature behaviour of the excitonic spectral line intensities, radiative decay time and the thermal quenching process of the bound exciton emission are described.