Synthesis of high resistive two-dimensional nonlayered Cr2S3 nanoflakes with stable phosphorus dopants by chemical vapor deposition

Abstract

Heteroatom doping and surface passivation for the nonlayered two-dimensional materials could tune their band structures for the application of electronic and optoelectronic devices. Herein, we report the exploration for a stable synthesis strategy of phosphorous doping in the nonlayered Cr2S3 nanoflakes via chemical vapor deposition. Single crystalline ultrathin P-doped Cr2S3 nanoflakes were achieved by tuning the hydrogen gas and sample–source distance, reaching a lateral size of 10–50 μm and a thickness down to 4 nm. The elemental characterization was confirmed with surface P-S and P-O bonds and bulk P-Cr bonds, indicating the surface passivation and lattice incorporation of P atoms. More importantly, the electrical resistivity of P-doped Cr2S3 nanoflakes was demonstrated to be 104 times compared to that of intrinsic Cr2S3, which could be explained by the liftup of Fermi level and surface passivation. Our work highlights phosphorous doping nonlayered Cr2S3 as tuning the electronic structure for achieving more intrinsic resistive samples. The heteroatom doping and surface passivation introduce a rational route for realizing the controllable electronic properties and provide more application potentials in the 2D electronic devices.