Novel 2D materials with interesting properties have been synthetized and characterized recently. In particular, unlike graphene, silicene or germanene, phosphorene has attracted a lot of attention because of its intrinsic band gap. This property allows for a wide range of applications where semiconductor thin films are traditionally used (e.g. electronics, optoelectronics, thermoelectrics). For each application, the device efficiency depends on how well an electrical current is extracted from the active materials, and depends on a variety of electron scattering processes. Some of these scattering processes can considerably improve or degrade device efficiencies. In this contribution we focus on non-radiative electron-hole pair generation and recombination processes, i.e. impact ionization (charge carrier multiplication) and Auger processes (charge carrier recombination). The rate of these processes is calculated from first principles and their effects on device operation are estimated.