Enhanced Absorption in MoS2/Hg0.33Cd0.66Te Heterostructure for Application in Solar Cell Absorbers

The heterostructure of mercury cadmium telluride (Hg
_0.33
Cd
_0.66
Te) and monolayer MoS
₂
with Van der Waals (VdW) interaction is suggested for tuning the optical absorption in visible region. The calculations are performed using density functional theory (DFT). From the results, it is found that for molybdenum disulfide (MoS2) absorption is high in the ~390-430 nm range of visible region and for mercury cadmium telluride (Hg
_0.33
Cd
_0.66
Te) absorption is high in the ~310-350 nm. However, absorption in the MoS
₂
/Hg
_0.33
Cd
_0.66
Te heterostructure increases with the wavelength and also shifts towards the red region of the visible spectrum, resulting into a well known red-shift phenomenon. Moreover, higher absorption is seen (entirely in visible region) in the heterostructure in the desired visible region range (λ ~640-710 nm) of the spectrum required for application in optoelectronic devices. The heterostructure results into semi-metallic or negligible indirect bandgap creation in contrast to direct bandgap observed in individual MoS
₂
and Hg
_0.33
Cd
_0.66
Te structures. The heterostructure can find application in Schottky barrier solar cell absorbers.