Synthesis Of Metal Oxide Nanocomposites Research Articles

Current scenario on biogenic synthesis of metal oxide nanocomposites using plant specimens and their application towards treatment of wastewater.

Various industries such as textile, leather, and paper mills discharge huge amount of industrial effluents to the environment containing unconsumed dyes and toxic heavy metal ions which are very harmful and carcinogenic in nature. The increase in water pollution is adversely impacting the ecosystems and human health. Now, it has become a great challenge to treat the contaminated water/wastewater. Photocatalysis and adsorption are the two techniques gaining significant attention for the removal of toxic pollutants from wastewater effectively. In this regard, metal oxide-based nanomaterials and their composites have gained profound attention in photocatalytic degradation as well as adsorptive removal of toxic pollutants from water due to their chemical reactivity, higher surface area, regeneration efficiency, ample adsorption sites, intriguing photocatalytic activity, and cost-effectiveness. However, the conventional methods, employed to synthesize these metal oxide nanocomposites, involve the use of toxic chemicals which again produce secondary pollutants. Among all biological materials, the use of plant biomolecules is found to be the most effective way to synthesize stable nanomaterials, as the phytoconstituents of plants act as reducing, capping, and stabilizing agent. It is experimentally proved that bio-based nanocomposites have tremendous potential towards the degradation of environmental pollutants. Thus, there is a great need to work on the synthesis of some novel plant-based metal oxide nanocomposites and their applications in the field of water treatment. This review mainly discusses the metal oxide nanocomposites synthesized using plant specimens and their various applications towards treatment of water/wastewater.

A Brief Review on Synthesis of Metal Oxide Based Nanocompositesandtheir Photocatalytic Applications

Nanocomposite, a multiphase solid material which is having the phases of one, two, or three dimensions less than 100 nanometers. These materials have the physical and chemical properties which depend on the morphology and the interfacial characteristics of the component materials. Metal oxide nanocomposites have proven themselves their importance in the present time with a wide variety of applications in every industrial sector. Wet chemical methods are one of the simplest routes for the synthesis of the metal oxide nanocomposites, and they are cost effective as well. For the synthesis of the complex matrix-based metal oxide nanocomposites, Co-precipitation is the method used. The simple synthesis methods make them unique material for different applications. This review paper discusses the synthesisof metal oxide nanocomposites and their applications.

ZnO/CuO nanocomposites from recycled printed circuit board: preparation and photocatalytic properties.

Cost-effective recycling of e-waste (from computer printed circuit boards, PCB's) for the synthesis of metal oxide nanocomposites is demonstrated. Metals in electronic components of waste memory slots were leached out using nitric acid (HNO3). Compositional analyses of the filtrate obtained after leaching were 66wt.% Cu, 27.7wt.% Zn, and 6.2wt.% Ni. The leached out metal salt solutions were subjected to alkaline hydrothermal treatment to synthesize nanocomposites. Two nanoparticle samples were prepared, one without any stabilizing agent and another sample with PVP as a stabilizing agent. XRD, HR-XRD, HR-TEM, UV-DRS, UV-visible spectroscopy was used to characterize the as-prepared metal oxide nanoparticles. The analysis showed the formation of ZnO/CuO nanocomposites only. No nickel oxide component was precipitated under the studied hydrothermal experimental conditions. Most of the ZnO/CuO nanocomposite particles obtained by this route consisted of fine ZnO nanostructures precipitated on CuO cores. The ZnO and CuO components exhibit both direct and indirect band gaps in the visible range. The nanocomposites demonstrate good visible light photo-Fenton methyl orange (MO) degradation by pseudo-zero order kinetics.

Synthesis of metal oxide nanocomposites from self-assembled block copolymer templates as cathode materials for all-solid-state lithium batteries

Self-assembled structures are useful for fabrication of nanostructures as a sustainable process with minimum energy consumption. Alternately stacked layers on a nanometre scale are produced by adsorption process denoted as layer by layer process, however, shape is limited in layers and chemical composition is also limited. Superlattice structures are produced by sputtering or self-assembly process using nanoparticles. But the construction of three-dimensional ordered inorganic nanocomposite structures remains a great challenge. All-solid-state lithium batteries (LiBs) are attracting much attention as innovative devices for upsized safety secondary batteries with high energy density. However, bulk-type all-solid-state LiBs face a number of hurdles, particularly the construction of an electrochemically favourable interface between the solid Li electrolytes and the active materials. In this study, we synthesised inorganic nanocomposite cathode materials by using self-assembled block copolymers (BCPs) as templates; this nanocomposite was composed of Li0.5La0.5TiO3 (LLT) as the electrolyte and LiCoO2 (LCO) as the cathode active material. Several LCO/LLT ratios were examined with the goal of producing a nanocomposite for use in all-solid-state LiBs. This nanostructured material, with the electrochemically favourable interface between electrode and electrolyte, resulted in a high capacity even at a high LCO content. The process we used to prepare the nanocomposite is expected to be versatile for producing other highly functional devices, such as quantum dot solar cells, thermoelectrics, and solid oxide fuel cells.

Gas Semiconducting Sensors Based on Metal Oxide Nanocomposites

This paper reviews the important problems associated with the synthesis of metal-oxide nanocomposites, charge transfer phenomena in these composites, their conductive and sensory properties, modeling of sensory effect and the role on this sensory effect of the electronic structure of the metal oxide. The size of metal particles and temperature significantly influence the efficiency of such systems. However, the electronic interactions between the different components of the nanocomposite films play the dominant role in the exploitation of the properties of such sensory systems. Depending on the chemical nature of the analyzed gas and the electronic structure of the semiconducting metal oxides, such interactions can result in either an increase or a decrease of the sensory effect. Thus, by varying the electronic structure of the metal oxide composite sensors as well as the temperature and size of the metal-oxide nanoparticles, the inherent characteristics of the sensor can be changed and tailored for detection of various gases. Such findings clearly open up new opportunities for development of novel selective sensors.

Synthesis and characterization of tanninsulfonic acid doped polyaniline–metal oxide nanocomposites

AbstractComposites of conducting polymers and metal oxides have a potential role in electronic devices because of their enhanced physical and electronic properties. An in situ synthesis of metal oxide nanocomposites of polyaniline (PANI) and tanninsulfonic acid doped PANI was carried out at −10°C with two different ratios of aniline to sodium persulfate (oxidant) and the simultaneous incorporation of TiO2, Al2O3, and ZnO nanopowders. The products were characterized by X‐ray diffraction (XRD), thermal analysis, spectroscopy, and electrical conductivity measurements. XRD and thermogravimetric analysis confirmed the presence of the metal oxide in the final product, whereas the spectroscopic characterization revealed interactions among the tannin, metal oxides, and PANI. The electrical properties were determined by four‐point‐probe bulk conductivity measurements. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2012