Route to n-type doping in SnS

SnS is intrinsically a p-type semiconductor, and much effort has been made to attain n-type conduction. In this letter, we performed density functional theory calculations to seek an effective doping route for n-type SnS. It was found that aliovalent doping of SnS by Sb or Bi is not effective due to their high formation enthalpies; while the isovalent Pb-substitution of the Sn sites largely reduces formation enthalpies of Sn and Pb interstitials, which explain the recently demonstrated n-type conduction in the Sn1−xPbxS films fabricated under low H2S pressures.