• • The phonon energy harvesting strategy achieves a photoluminescence (PL) enhancement in WS2 homobilayers by transferring phonon energy from CVD to ME monolayers, with the degree of enhancement regulated by trion or phonon populations. This offers a pathway to mitigate energy dissipation in 2D optoelectronic devices.
• • The trion-to-exciton conversion is promoted by the harvested phonon energy, leading to significant PL enhancement. This conversion process is critical for improving the quantum yield of TMD monolayers, which is often limited by trion formation.
• • The strategy is universally applicable to different TMD homobilayers, as demonstrated with WS2 and potentially extendable to MoS2 and other TMDs. This universality suggests broad industrial relevance for various 2D material systems.
• • The use of defect-induced asymmetry in phonon populations between CVD and ME monolayers enables directional phonon transfer. This asymmetry is key to the energy harvesting mechanism and can be engineered through material synthesis and stacking.