研究実績の概要 |
The study on geometry optimization of displaced dopant indicates that the dopant did not occupy substitutional site in MoS2 upon relaxation. Our results pointed out an important aspect of doping into MoS2 that simple cationic substitutional may be carefully decided in computational modelling of defects since there may be more likelihood that dopant at off-cationic site gives minimum energy configuration. It was surprisingly observed that interlayer separation increases after structural relaxation of charged supercells. The findings of our work are technologically very important and this effect has never been observed for MoS2 to best of our knowledge. Increased interlayer separation is advantageous to convert MoS2 from bulk to monolayer without hurting the material during conventional mechanical or chemical methods of achieving monolayers. The symmetry analysis indicates that centrosymmetric structure of pure MoS2 is transformed into non-centrosymmetric structure upon doping RE atoms into one layer of double layer structure of the material. It predicts the usage of RE doped MoS2 for valley polarization and piezoelectric applications. The value of band gap is observed to change in wide range from 0.55-1.53 eV upon doping which predicts usage of MoS2 for applications in detectors and emitters applicable in infrared to visible region of electromagnetic spectrum. In summary, we predict a class of MoS2 based materials having tuneable properties useful for miniature optical and magnetic devices to fulfil the future demands.
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