Hydrogen-assisted synthesis and optical properties of single-crystalline Cd0.9Mn0.1S nanobelts

High quality Cd0.9Mn0.1S nanobelts have been synthesized using a one-step thermal evaporation method in large scale. Their morphology and microstructures were determined by X-ray powder diffraction, scanning electron microscopy, high-resolution transmission electron microscopy, energy-dispersive X-ray spectroscopy, Raman spectroscopy and photoluminescence spectroscopy. The observations revealed that the as-synthesized Cd0.9Mn0.1S nanobelts were high quality single crystalline with hexagonal wurtzite structure. The nanobelts grew along [0 -1 1 0] direction with side surfaces of +/- (0 0 0 1) and top surfaces of +/- (2 1 1 0). The nanobelts can range in length from several tens to a hundred microns, in thickness about 50 nm and in tapered width 50 to 300 nm. A hydrogen-assisted vapor-liquid-solid (VLS) combined with vapor-solid (VS) formation mechanism is also proposed to interpret the growth of Cd0.9Mn01S nanobelts in our work. The room-temperature photoluminescence spectrum of Cd0.9Mn0.1S nanobelts featured two luminescence peaks around 515 and 596 nm, which could be attributed to surface state emission and Mn2+ ion intra-3d (4T1-6A1) transition, respectively.