Random coincidences of nuclear events can be one of the main background sources in low-temperature calorimetric experiments looking for neutrinoless double-beta decay, especially in those searches based on scintillating bolometers embedding the promising double-beta candidate $$^{100}$$ 100 Mo, because of the relatively short half-life of the two-neutrino double-beta decay of this nucleus. We show in this work that randomly coinciding events of the two-neutrino double-beta decay of $$^{100}$$ 100 Mo in enriched Li $$_2^{100}\,\mathrm{MoO}_4$$ 2 100 MoO 4 detectors can be effectively discriminated by pulse-shape analysis in the light channel if the scintillating bolometer is provided with a Neganov–Luke light detector, which can improve the signal-to-noise ratio by a large factor, assumed here at the level of $${\sim }750$$ ∼ 750 on the basis of preliminary experimental results obtained with these devices. The achieved pile-up rejection efficiency results in a very low contribution, of the order of $${\sim }6\times 10^{-5}$$ ∼ 6 × 10 - 5 counts/(keV $$\cdot $$ · kg $$\cdot $$ · y), to the background counting rate in the region of interest for a large volume ( $${\sim }90$$ ∼ 90 cm $$^3$$ 3 ) Li $$_2^{100}\,\mathrm{MoO}_4$$ 2 100 MoO 4 detector. This background level is very encouraging in view of a possible use of the Li $$_2^{100}\,\mathrm{MoO}_4$$ 2 100 MoO 4 solution for a bolometric tonne-scale next-generation experiment as that proposed in the CUPID project.
