Controllable fabrication and broadband near-infrared luminescence of various Ni2+-activated ZnAl2O4 nanostructures by a single-nozzle electrospinning technique

Phys Chem Chem Phys. 2012 Oct 21;14(39):13594-600. doi: 10.1039/c2cp42235b.

Abstract

By finely tuning the electrospun parameters (feeding rate of solution, working voltage and distance, etc.) and concentration of inorganic salts, various ZnAl(2)O(4) nanostructures (nanoparticles, nanonecklaces, nanofibers, nanotubes and hollow micromelts) were controllably synthesized by a single-nozzle electrospinning technique. The formation mechanisms of different ZnAl(2)O(4) nanostructures, including 'oriented attachment' mechanism, 'gas-push' mechanism, etc., were proposed to elucidate the morphology of the nanostructures and microstructure evolvement process. The morphology and microstructure of calcined electrospun nanostructures were considered to be mainly dependent on two factors, i.e. concentration of inorganic salts and size of as-prepared electrospun nanofibers. Using Ni(2+) ions as activators, broadband near infrared (NIR) emission covering 1000-1400 nm peaking at about 1176 nm was detected in Ni(2+)-doped ZnAl(2)O(4) nanostructures. The broadband NIR emission at around 1.3 μm optical communication window with a long lifetime of ~640 μs makes Ni(2+)-doped ZnAl(2)O(4) nanostructures as a promising candidate for micro/nano-broadband optical amplifiers, fibers, etc.