Unraveling the Peculiarities in the Temperature-Dependent Structural Evolution of Black Phosphorus

Black phosphorous (BP) is one of the important emerging two-dimensional systems. We have undertaken a structural investigation of BP in the temperature range of 320 K to 85 K using synchrotron X-ray diffraction (XRD) studies. The XRD pattern of BP is heavily influenced by the preferred orientation effects. Collection of the diffraction pattern in a standard capillary geometry with controlled capillary rotations perpendicular to the X-ray direction permitted us to provide insights to the effects of the preferred orientation. In the range of 320 K to 85 K, BP remains in the so-called “A17” orthorhombic structure. Lattice parameters show a regular shrinkage with the lowering of the temperature as expected for any elemental metallic system. Dense temperature sampling permitted us to observe a small but clear deviation from the linear behavior in of one of the in-plane lattice parameters. This temperature-dependent structural evolution seems to provide some insights into the temperature dependence of the macroscopic properties of BP such as the Hall coefficient, thermal conductivity, etc.