Localized Excitons in Zn-Porphyrin Covalently Functionalized MoS₂ and WS₂

We successfully functionalized MoS2 and WS2 with Zn-porphyrin through 1,2-dithiolane addition. This createsmixed 0-2 dimensional materials since porphyrins are discreteon the basal plane of TMDs. This localization results in a new emissionband with a 3.5 ns lifetime at 77.5 K with an excitation power of17 W/cm(2) in the near-infrared (NIR) region (1.40-1.51eV), which originates from charge-separated states between ZnP andWS(2). The optical response of excitonic species, includingtrion, biexcitons, and excitons, is substantially enhanced at theporphyrin absorption region, supporting electron transfer betweenZnP and WS2. Sensing time-response improves after functionalization,suggesting that electrons injected from ZnP to TMDs contribute tofilling trap states. Incorporating ZnP also enhances the stabilityof WS2 and MoS2 against atmospheric photodegradation.Theoretical modeling supports these findings, suggesting an intimaterelationship between orbitals in the ground and excited states ofporphyrin and TMDs.