Synthesis of novel nano-flowers assembled with nano-petals array of stannous oxide

► Novel nano-flowers/nano-petals of SnO were synthesized by hydrothermal method. ► The average crystallite size of the SnO nanoparticles was calculated about 22 nm ► Direct optical band gap of 3.13 eV was acquired by using Davis-Mott model. ► PL exhibited prominent violet emission at 398nm correspond to direct band emission.