We report on molecular beam epitaxial growth and properties of InAs/In0.66Ga0.34As/In0.77Al0.23As metamorphic quantum wells (QWs) with submonolayer InSb insertions grown on GaAs(001) substrates. InAlAs metamorphic buffer layers with linear and convex profiles are used to match gradually the lattice parameter from GaAs one to that of In0.77Al0.23As barriers, with the latter profile showing the better structural quality. A single type-II InSb insertion in the InAs QW shifts the photoluminescence (PL) peak maximum well beyond 3 mu m due to the recombination of holes localized in the InSb well with electrons confined in the InAs/InGaAs QW. The mid-infrared PL in the structures with and without InSb insertion survives up to room temperature. (C) 2017 Elsevier B.V. All rights reserved.