Adsorption of cysteine molecule on intrinsic and Pt-doped graphene: A first-principle study

The adsorption of cysteine molecule on intrinsic and Pt-doped graphene sheets was studied by density functional theory calculations. Compared with the intrinsic graphene, Pt-doped graphene strongly adsorbs cysteine molecules with higher binding energy value and shorter distance between the cysteine molecules and the graphene surface. The calculation of electron transfers and dipole moment supports that the electronic properties of Pt-doped graphene change more significantly than that of intrinsic graphene after the cysteine molecular adsorbed. Furthermore, the density of states results shows a larger orbital hybridization between cysteine and Pt-doped graphene sheet. Therefore, Pt-doped graphene is a promising candidate for sensor detecting a variety of S-containing proteins and metalloenzymes.