Synthesis and characterization of brush-like ZnO nanorods using albumen as biotemplate

Abstract

Nanobastões de ZnO com morfologia similar à de escovas, estrutura cristalina do tipo wurtzita (hexagonal), diâmetro médio de 90 nm e comprimento ≥1 μm, foram preparados por calcinação (700 ° C) do material híbrido (Zn(II)/albumina) obtido pelo método sol-gel reagindo-se acetato de zinco e clara de ovo, em meio aquoso. O material foi caracterizado por difratometria de raio-X de pó (XRD), microscopia eletrônica de varredura (MEV) e de transmissão (TEM), análise termogravimétrica (TGA/DTA), e espectroscopia FT-IR e de fotoluminescência (PL). A área superficial foi determinada como sendo igual a 6,91 m 2 g -1 pelo método BET. Os eventos térmicos no TGA/DTA foram consistentes com a decomposição da albumina a 300 °C e a formação final de ZnO em 578,5 °C. Os resultados mostraram que a albumina desempenha papel essencial na formação dos nanobastões de ZnO, atuando como molde.Crystalline ZnO nanorods with wurtzite-like structure and average diameter of 90 nm and length ≥1 μm, was prepared by calcination (700 °C) of a Zn(II)/albumen hybrid obtained by solgel method, by the reaction of Zn(II) acetate and egg white (albumen), in aqueous solution. The material was characterized by powder X-ray diffraction (XRD), scanning electron (SEM) and transmission electron microscopy (TEM), thermogravimetric analysis (TGA/DTA), N 2 adsorption/ desorption (BET method), FT-IR and photoluminescence (PL) spectroscopy. The surface area was determined to be 6.91 m 2 g -1 by BET method. The TGA/DTA thermal events were consistent with the decomposition of albumen at 300 °C and final formation of ZnO at 578.5 °C. The results showed that albumen act as template playing essential role on defining the formation of ZnO nanorods with brush-like morphology.Keywords: brush-like ZnO nanorods, sol-gel method, egg white (albumen) IntroductionIn recent years, there have been many reports on novel preparation and characterization methods of nanomaterials, based on metal oxide semiconductors in general and ZnO in particular, owing to their special properties. 1 ZnO nanoparticles, with a wide band gap has found to be an efficient candidate for utilization in optical devices operating at room temperature, because of their catalytic/photocatalytic activity and use as CO gas sensor. Furthermore, ZnO is a material with excellent chemical, thermochemical and mechanical stability, which can be used to absorb ultraviolet light, protecting us against this hazardous radiation. 2 Nanostructured ZnO with as different shapes as one dimensional (1D) nanowires, 3-7 nanotubes, 8,9 nanorods 10 and nanobelts, 11 two dimensional (2D) nanostructures such as nanosheets 12 and nanowalls 13 and some three dimensional (3D) nano/microstructures such as nanoflower and tetrapod like structures, [14][15][16][17] have been fabricated by means of various methods. Thus, the fabrication methods of ZnO nanomaterials can be classified into two categories: (i) vapor phase processes and (ii) solution phase routes. [18][19][20][21][22][23] Recently, solution phase routes including microemuls...

Structural, morphological and optical properties of Albumen mediated ZnO nanoparticles

“…Similar behaviour is exhibited for ZnO nanoparticles which has been reported earlier [14]. XRD pattern recorded for Albumen mediated ZnO nanoparticles is shown in Figure 1b …”

“…ZnO nanoparticles are being widely used in human health care commercial products due to its unique properties such as UV absorption, catalytic conductivity, magnetic and antimicrobial activities [12]. ZnO nanoparticles are completely differ from bulk ZnO material, since they are exhibited some unique characteristics such as high proportion of atoms on the surface of nanosized materials, light absorption, band gap, catalytic and antimicrobial activities [13,14]. Owing to its large surface-to-volume ratio ZnO nanoparticles gives rise to high reactivity towards biological responses [15].…”

Cobalt ferrite nano-composite coated on glass by Doctor Blade method for photo-catalytic degradation of an azo textile dye Reactive Red 4: XRD, FESEM and DRS investigations

“…The thermogram shows a minor weight-loss of 2.1% between 28 and 198 o C due to the loss of residual adsorbed water and surface capping oxidized ethylene glycol molecules. As shown in Table 1 [47,48]. Optical band gap of hydrothermally prepared cobalt ferrite nano-composite annealed at 300 o C was estimated using the Tauc relationship, ahυ = A(hυ-Eg) n , where a is the absorption coefficient, A is a constant, h is the Planck's constant, υ is the photon frequency, and Eg is the optical band gap [49].…”

Hydrothermal synthesis of zinc oxide nanoparticles using rice as soft biotemplate

“…Bio-inspired synthesis of ZnO nanoparticles has been achieved using environmentally and eco-friendly accepted systems. Several studies have been investigated the use of natural materials for ZnO nanoparticles synthesis such as DNA [12], silk [13], albumen [14], orange juice [15], pea starch [16], peptide structures [17] and etc. The use of nanoparticles derived from noble metals has spread in many areas involving medical fields, electronics, antibacterial textiles, etc.…”