The electrical, thermal, and thermoelectric properties of black phosphorus

Black phosphorus (BP) as a two-dimensional semiconductor has attracted tremendous interest in physics, chemistry, biology, and engineering fields. BP has a thickness-dependent bandgap and high carrier mobility, and its puckered honeycomb layer structure with in-plane anisotropy gives rise to unique electrical, thermal, optical, and other properties. These interesting properties provide new opportunities for the design of new devices. The prominent electrical and thermal properties of BP are orthogonal, and the Seebeck coefficients of BP, especially monolayer BP, are large, thus rendering the materials to be desirable in thermoelectric devices. In this Perspective, the recent developments of electrical, thermal, and thermoelectric properties of BP are described. The strategies to tailor the thermoelectric performance are highlighted, aiming at further development and applications in highly efficient thermoelectric devices.