S. Sasi Florence

Tailoring of Morphology and Optical Properties of Bishydrazone-Capped ZnSe Nanorods

Hydrazone derivatives containing heterocyclic moieties have interesting ligational features. Various heterocyclic base ligands have been gradually used to synthesize nanomaterials; however, adapting task-specific ligand systems to guide the synthesis path towards desirable nanostructures and morphologies is rare. In this article, bishydrazone was used as a ligand to purposely modify the morphological structure of the zinc selenide nanostructures via wet chemical reaction method at room temperature. The as-prepared ZnSe nanorods are relatively uniform with an average diameter of ~100 nm at the core and top diameter of 8–10 nm. UV-Vis spectrum of the products displayed absorption maxima at 390 nm. Therefore, the obtained ZnSe nanorods may have promising applications in blue emitters, catalysts, and gas sensors. The presence of bishydrazone in the ZnSe nanorods is confirmed by the Fourier transform infrared spectrum. It would be expected that bishydrazone could be used to prepare other nanoscale metal selenides with special morphologies and improved properties on a large scale.

Micropatterned Arrays of ZnSe Nanospheres as Antireflection Coatings

In this work, we demonstrate deposition of micro-arrays of ZnSe nanospheres on Si (100) substrate using simple thermal evaporation on a self-assembled sacrificial polystyrene (PS) mask. The results have been compared with the deposition on unpatterned gold catalyst- and SU-8 (negative photoresist)-coated Si substrates. The deposited ZnSe nanospheres properties were characterised by X-ray diffraction, atomic force microscopy (AFM), scanning electron microscopy (SEM), Raman, photoluminescence, and UV-vis spectroscopies. The X-ray diffraction patterns of the films exhibited reflection corresponding to the cubic (111) phase and showed polycrystallinity with a cubic (zinc blende) structure. The SEM and AFM images indicated that the particles were well dispersed and spherical in shape. The micro-arrays of ZnSe nanospheres on a self-assembled sacrificial PS mask showed excellent structural, morphological, and optical properties and demonstrated its usage in photovoltaic devices as an improved superior antireflective coating. The reflectance of the micro-arrays of ZnSe nanospheres on a self-assembled sacrificial PS mask decreased to nearly half of that of the ZnSe nanospheres fabricated on Au- and SU-8-coated Si substrates in the range of 300–800 nm. Due to the well aligned and patterned surfaces, these noble textured ZnSe nanospheres may be suitable for low cost, large area photovoltaic devices and other antireflection applications.

Green approach to synthesis and strain studies of ZnO nanoparticles

In this paper, a simple, facile and green approach to synthesis Gum Arabic (GA, a natural gum) assisted ZnO nanoparticles by using a wet chemical reaction method is reported. The synthesis of ZnO nanoparticles has been with the assistance of two different types of GA namely Acacia Senegal and Acacia Seyal. The effects of GA and the properties of Senegal and Seyal GA have been studied by using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM).In this paper, a simple, facile and green approach to synthesis Gum Arabic (GA, a natural gum) assisted ZnO nanoparticles by using a wet chemical reaction method is reported. The synthesis of ZnO nanoparticles has been with the assistance of two different types of GA namely Acacia Senegal and Acacia Seyal. The effects of GA and the properties of Senegal and Seyal GA have been studied by using X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM).