Silicon carbide (SiC) is a material with outstanding physical and mechanical properties, making it a leading material for components and devices operating at high temperature, high power and under harsh environments. Moreover, various lower-dimensional SiC structures, such as one-dimensional SiC nanotubes and nanowires have been synthesized, which has stimulated a lot of studies. In recent years, the graphene-like SiC structure, i.e. the possible material of two-dimensional single-atom-thick hexagonal sheets, has been investigated theoretically, and SiC nanoribbons are made by cutting SiC graphene-like sheets just like the graphene nanoribbons. Under first-principles computations, Ping Lou (pp. 1265–1277) systematically examines the electronic and magnetic structures, as well as the structural and electronic spin-transport properties, of zigzag SiC nanoribbons (ZSiC NRs) containing one isolated nonmagnetic impurity atom at different doping sites. It was found that without an applied electric field the ZSiC NRs can be tuned to be magnetic semiconducting, magnetic half-metallic, as well as magnetic metallic by controlling the doping position. Most of them have 100% spin transport polarization around the Fermi level and exhibit spin filtering behavior.