RESUMEN
In this article, a simple microwave route was applied for the synthesis of nanoflakes and dendrite-type beta-indium sulfide (In2S3) in high yield (> 97%), using a homogeneous mixture of indium(lll)chloride and thiourea in an ethylene glycol (EG)/polyethylene glycol (PEG400) solvent. The reaction was conducted in a simple domestic microwave oven (DMO). Powder X-ray diffraction (XRD), low resolution and high resolution transmission electron microscopy (LRTEM and HRTEM), selected area electron diffraction (SAED), and energy dispersive X-ray spectroscopy (EDS), were applied to investigate the crystallinity, structure, morphology, and composition of the In2S3 nano-materials. Both the as-synthesized and calcined In2S3 products were a body-centered tetragonal (bct) phase, observed by XRD and HRTEM. The length and width of the resulting nanoflakes were in the range of 70-600 nm and 4-10 nm, respectively. The optical band gap of the powder was determined by diffuse reflectance spectroscopy (DRS) and was found to be 2.44 eV. The electronic properties of the products were studied by measuring the optical absorption spectra using photoacoustic spectroscopy. The band gap calculated by this method was found to be 2.52 eV. A possible mechanism for the formation of nanoflakes/dendrites-type In2S3 was also discussed.
Asunto(s)
Cristalización/métodos , Indio/química , Indio/efectos de la radiación , Microondas , Nanoestructuras/química , Nanoestructuras/ultraestructura , Nanotecnología/métodos , Azufre/química , Azufre/efectos de la radiación , Ensayo de Materiales , Conformación Molecular , Nanoestructuras/efectos de la radiación , Tamaño de la Partícula , SemiconductoresRESUMEN
Nanoparticles of the CuInTe(2) (CIT) and CuInSe(2) (CIS) alloys have been prepared using the microwave-assisted polyol method. In this simple and quick reaction the polyol is both the solvent and the reducing agent. XRD studies show that nanoparticles of CIT and CIS are formed in the body-centered tetragonal structure and their average diameters are approximately 94 and approximately 83 nm, respectively. Electron microscopy studies show that these formed particles are poorly aggregated with a mean diameter of 100 and 85 nm, respectively. The products have been characterized by different analytical techniques, and the electronic properties have been measured using photoacoustic spectroscopy (PAS).