Unraveling the anomalous mechanoluminescence intensity change and pressure-induced red-shift for manganese-doped zinc sulfide

Mechanoluminescence (ML) has promising applications such as stress sensors and many other fields, which raises intensive research attention and enthusiasms in the past few decades. However, accurate characterizations of the ML process with high temporal and spectral resolution remain a considerable challenge for the current scientific community. Here, an advanced ML characterization system based on the dynamic diamond anvil cell (dDAC) is developed to achieve flexible modulations of ML performances. Upon compression, the ML spectra of manganese-doped zinc sulfide (ZnS:Mn) show a large red-shift (~45 nm) and a volcano-trend of the ML intensity, where the cumulative ML intensity is solely dependent on the pressure change. DFT calculations identify the coupling of Mn-doping and surface vacancies is playing a crucial role in contributing to the improvement of ML through the band offset. The suppression of the vacancies formation on the surface by the applied pressure over 4 GPa leads to the decreases of the ML intensity. This work provides a brand new ML color and intensity tuning strategy and offers a promising method to explore the ML mechanism.