Engineering and controlling the electronic properties of zigzag and armchair boron nitride nanotubes with various concentrations of oxygen impurities

•Effect of oxygen impurities on the electronic properties of ASWBNNTs and ZSWBNNTs.•Controlling electronic properties by using various concentrations of O impurities.•The electronic band gap value decreased with various concentrations of O impurities.•ASWBNNTs changed from insulator to semiconductor using 2-hexagonal of O impurities.•The behavior of ASWBNNTs and ZSWBNNTs become metallic with 7 O impurities.