<p>Phonon management in van der Waals (vdW) layered materials has become an area of increasing demand, driven by rapid advancements in electronic and optoelectronic devices. A fundamental challenge in the phonon management of these materials is the effective harvesting of phonons between layers to minimize energy dissipation. Here, we demonstrate a novel phonon energy harvesting strategy in vertically stacked transition metal dichalcogenide (TMD) homobilayers, whose constituent monolayers are prepared individually by mechanical exfoliation (ME) and chemical vapor deposition (CVD) methods. In these systems, owing to the defect-induced asymmetry of phonon populations between layers, the phonon energy can be transferred from CVD monolayers to ME monolayers and then sufficiently utilized to promote the trion-to-exciton conversion in homobilayers for significant photoluminescence (PL) enhancement. The degree of such PL enhancement can be further regulated by varying either the trion or phonon populations involved in the conversion process. This strategy is universally applicable to different TMD homobilayers, presenting a new avenue for phonon energy harvesting in vdW layered materials.</p>