The Ag+ induced solution-liquid-solid growth, photoluminescence and photocatalytic activity of twinned ZnSe nanowires

Cubic ZnSe nanowires with periodically alternating twins along the wire growth direction are synthesized in the ZnCl2-Na2SeO3-AgNO3-ethylenediamine (EN)-ethylene glycol (EG)-polyvinyl-pyrrolidone (PVP) solvothermal system at 180A degrees C for 12 h. The twinned ZnSe nanowires have diameters of 75 +/- 10 nm and lengths of > 10 micrometers, and grow along aOE (c) 111 > direction. The role of AgNO3 in the formation of ZnSe nanowires was investigated, and an Ag+ induced solution-liquid-solid growth mechanism is also proposed to account for the conversion of microspheres assembled from ZnSe nanocrystallites into ZnSe nanowires. Compared with ZnSe microspheres, the as-prepared twinned ZnSe nanowires exhibit stronger band edge emissions of the wurtzite- and zinc-blende-structured ZnSe and lower deep defect related emission, and their photocatalytic ability is weaker than that of ZnSe microspheres. The results suggest that this simple, mild, one-step solution approach to fabricate ZnSe nanowires may be employed for the synthesis of other selenium compounds with one dimensional nanostructures, and provides opportunities for both fundamental research and technological applications.