Engineering of MoS2 nanoribbons as high-performance materials for biosensing applications

[Display omitted] •AMoS2NR-O-H structure has the lowest binding and optimization energies.•When biomolecules are placed parallel to AMoS2NR-O-H, the system is more stable.•Placement of the biomolecules on AMoS2NRs significantly reduces the band gap value.•S atom plays an important role in the interactions between AMoS2NR and biomolecules.•In AMoS2NR-O-H-X, edge absorption shows a red shift in the range 200–800 nm. Today, biosensors play a key role in industry and medicine as detectors for a variety of biomolecules. The most important factors in these devices are the accuracy and rate of detection by the source selected for biosensing. In this work, we first placed Cytosine, Methionine, Thymine and Glutamine biomolecules on armchair MoS2 nanoribbons passivated with H and O atoms (AMoS2NR-H-O) and formed AMoS2NR-H-O-X structures, where X is the placed biomolecule. A first-principles theoretical study was performed to investigate the effects of these placements on the band structure, electron density, density of states, dielectric function and absorption spectrum of AMoS2NR-H-O. Our results showed that by placing biomolecules on the AMoS2NR-H-O, the band gap value changes between 0.3 and 0.75 eV. We found that sulfur atom has the main contribution in the interactions between AMoS2NR-H-O and biomolecules. The type of functional groups that make up the biomolecules plays an important role in the interactions between the biomolecules and S atoms (X-S interactions). Also, the placement of the biomolecules on AMoS2NR-H-O causes a red shift in the absorption edge. The extensive changes in the optoelectronic properties of AMoS2NR-H-O suggest that this compound can be a good platform for biosensing applications.