Single crystals of MoS2 doped with Re, Fe, and Au have been grown by the chemical vapor transport method using bromine and iodine as a transporting agent. Detailed characterization of the materials are carried out by using X-ray diffraction, scanning transmission electron microscopy (STEM), raman, piezoreflectance, photoreflectance, electrolyte electroreflectance, and photoresponse.

X-ray analysis confirm that undoped and Fe-doped MoS2 are two-layer hexagonal (2H) structures while Re- and Au-doped MoS2 are three layer rhombohedral (3R) structure. STEM image figured out that Re and Au atoms are uniformly distributed on the MoS2 and substitute the Mo lattice whereas Fe atoms are not uniformly distributed on MoS2, segregate into groups and disperse unevenly. Raman measurements on the basal plane revealed the two dominant first order Raman-active modes A1g and E2g while on the edge plane revealed the three dominant first order Raman-active modes E1g, A1g and E2g.

The influence of doping on the optical properties are characterized by temperature-dependent PzR spectroscopy measurements in the temperature range between 25 and 300 K. The energies and broadening parameters of the A and B excitons have been determined accurately via a detailed line shape fit of the PzR spectra. We observed that Re and Au doping strongly reduces the splitting between A and B excitons as well as it causes the redshift of observed transitions in relation to the undoped MoS2 whereas the splitting between A and B for Fe-doped MoS2 is similar with undoped one. EER, PR, and photoresponse were carried out to confirm the origin of the broad peak as observed in PzR spectra.

Single crystals of MoS2 doped with Re, Fe, and Au have been grown by the chemical vapor transport method using bromine and iodine as a transporting agent. Detailed characterization of the materials are carried out by using X-ray diffraction, scanning transmission electron microscopy (STEM), raman, piezoreflectance, photoreflectance, electrolyte electroreflectance, and photoresponse.

X-ray analysis confirm that undoped and Fe-doped MoS2 are two-layer hexagonal (2H) structures while Re- and Au-doped MoS2 are three layer rhombohedral (3R) structure. STEM image figured out that Re and Au atoms are uniformly distributed on the MoS2 and substitute the Mo lattice whereas Fe atoms are not uniformly distributed on MoS2, segregate into groups and disperse unevenly. Raman measurements on the basal plane revealed the two dominant first order Raman-active modes A1g and E2g while on the edge plane revealed the three dominant first order Raman-active modes E1g, A1g and E2g.

The influence of doping on the optical properties are characterized by temperature-dependent PzR spectroscopy measurements in the temperature range between 25 and 300 K. The energies and broadening parameters of the A and B excitons have been determined accurately via a detailed line shape fit of the PzR spectra. We observed that Re and Au doping strongly reduces the splitting between A and B excitons as well as it causes the redshift of observed transitions in relation to the undoped MoS2 whereas the splitting between A and B for Fe-doped MoS2 is similar with undoped one. EER, PR, and photoresponse were carried out to confirm the origin of the broad peak as observed in PzR spectra.

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