Synthesis of mesoporous sulfur-doped Ta2O5 nanocomposites and their photocatalytic activities.

Mesoporous sulfur (S)-doped Ta2O5 nanocomposites have been synthesized for the first time through the sol-gel reaction of tantalum chloride and thiourea in the presence of a F127 triblock copolymer as structure directing agent. The as-formed mesophase S-doped Ta2O5 hybrid gels were calcined at 700°C for 4h to obtain mesoporous S-Ta2O5 nanocomposites. The experimental results indicated that the surface area of the S-doped Ta2O5 was up to 50m(2)g(-1) and the pore diameter was controllable in the range of 3-7.

Fabrication and characterization of a highly sensitive hydroquinone chemical sensor based on iron-doped ZnO nanorods.

Herein, we report the development of a simple and highly sensitive hydroquinone (HQ) chemical sensor based on an electrochemically activated iron-doped (Fe-doped) zinc oxide nanorod (ZnO NR) modified screen-printed electrode (SPE). The Fe-doped ZnO NRs were prepared using a hydrothermal process and their morphological, crystal, compositional and optical properties were characterized in detail. The detailed characterizations showed that the NRs are densely grown, well-crystalline and possess a wurtzite hexagonal phase.

Fabrication and Characterization of Field Effect Transistor Based on High-Aspect Ratio Sulfur-Doped ZnO Nanowires.

Well-crystalline sulfur (S) doped ZnO nanowires have been grown via a simple thermal evaporation process on Si substrate using high purity zinc and sulfur powders in presence of oxygen. The as-grown S:ZnO nanowires were characterized in terms of their morphological structural, compositional and optical properties using several techniques such as FESEM, TEM, XRD, EDS and PL. The morphological characterizations revealed that the as-grown nanowires had diameters in the range of 60-100 nm with lengths 5-15 μm.

Fabrication and Characterization of n-ZnO Hexagonal Nanorods/p-Si Heterojunction Diodes: Temperature-Dependant Electrical Characteristics.

This paper reports the temperature-dependant electrical characteristics of n-ZnO hexagonal nanorods/p-Si heterojunction diodes. The n-ZnO hexagonal nanorods were grown on p-Si substrate by a simple thermal evaporation process using metallic zinc powder in the presence of oxygen. The spectroscopic characterization revealed well-crystalline nanorods, quasi-aligned to the substrate and possessing hexagonal shape.

Quantum chemical investigations of AlN-doped C60 for use as a nano-biosensor in detection of mispairing between DNA bases.

Quantum chemical calculations were carried out to study the electronic structure and stability of adenine-thymine and the rare tautomer of adenine-thymine base pairs along with their Cu 2+ complexes and their interactions with AlN-modified fullerene (C58AlN) using Density Functional Theory (B3LYP method). Since, these two forms of base pairs and their Cu 2+ complexes have almost similar electronic structures, their chemical differentiation is an extremely difficult task. In this investigation, we have observed that AlN-doped C 60 could be used as a potentially viable nanoscale sensor to detect these two base pairs as well as their Cu2+ complexes.

Low-temperature growth of aligned ZnO nanorods: effect of annealing gases on the structural and optical properties.

Aligned ZnO nanorods were grown on ZnO/Si substrate via simple aqueous solution process at low-temperature of - 65 degrees C by using zinc nitrate and hexamethylenetetramine (HMTA). The detailed morphological and structural properties measured by FESEM, XRD, EDS and TEM confirmed that the as-grown nanorods are vertically aligned, well-crystalline possessing wurtzite hexagonal phase and grown along the [0001] direction. The room-temperature photoluminescence spectrum of the grown nanorods exhibited a strong and broad green emission and small ultraviolet emission.

Highly selective colorimetric detection and preconcentration of Bi(III) ions by dithizone complexes anchored onto mesoporous TiO2.

We successfully developed a single-step detection and removal unit for Bi(III) ions based on dithizone (DZ) anchored on mesoporous TiO2 with rapid colorometric response and high selectivity for the first time. [(DZ)3-Bi] complex is easily separated and collected by mesoporous TiO2 as adsorbent and preconcentrator without any color change of the produced complex onto the surface of mesoporous TiO2 (TiO2-[(DZ)3-Bi]) at different Bi(III) concentrations. This is because highly potent mesoporous TiO2 architecture provides proficient channeling or movement of Bi(III) ions for efficient binding of metal ion, and the simultaneous excellent adsorbing nature of mesoporous TiO2 provides an extra plane for the removal of metal ions.

Applications of ZnO nanoflowers as antimicrobial agents for Escherichia coli and enzyme-free glucose sensor.

Well-crystalline ZnO nanoflowers were prepared by a facile solution process and their applications as an antimicrobial agent against Escherichia coli and enzyme-free glucose sensor have been studied. The morphological, structural, compositional, and optical properties of ZnO nanoflowers were characterized by various techniques, which confirmed the well-crystalline wurtzite hexagonal phase. The minimum inhibitory concentration of ZnO nanoflowers for inhibiting the growth of Escherichia coli was found to be 25 microg/ml.

Visible-light-driven photocatalytic and chemical sensing properties of SnS2 nanoflakes.

This work demonstrated the successful and facile large-scale synthesis and characterizations of SnS2 nanoflakes. The detailed morphological studies revealed that the synthesized products were nanoflakes and were grown in large quantity. The XRD pattern and detailed compositional studies confirmed that the synthesized SnS2 nanoflakes were well-crystalline and possessing hexagonal SnS2 phase.

One-pot synthesis and characterization of Nb2O5 nanopowder.

Nanosized niobium oxide powders were synthesized with a yield of approximately 87% using a simple and facile soft-chemical process. Niobium pentachloride (Nb2Cl5) was used as the precursor which was first converted into niobium ethoxide and then hydrolysed with water to synthesize niobia nanopowder. The synthesized powder was calcined at 500 degrees C for phase conversion to end-centered monoclinic as confirmed by diffraction studies and elemental analysis with a chemical composition in the ratio of Nb:O as 1:2.

Understanding the effect of flower extracts on the photoconducting properties of nanostructured TiO2.

Here we report an easy method to improve the optoelectronic properties of commercially available TiO2 nanopowder using extracts of various flowers viz. Calendula Orange (CO), Calendula Yellow (CY), Dahlia Violet (DV), Dahlia Yellow (DY), Rabbit flower (RF), Sweet Poppy (SP), Sweet Williams (SW) and their Mixed Extracts (ME). Various analysis techniques such as UV-Vis, FTIR, FESEM, XRD, and Raman spectroscopy were used to characterize for elemental, structural and morphological properties of the unmixed/mixed TiO2 nanopowder.

Temperature dependant characteristics of zinc oxide nanorods based heterojunction diode.

Temperature-dependant characteristics of heterojunction diode made by n-ZnO nanorods grown on p-silicon substrates has been characterized and demonstrated in this paper. ZnO nanorods were grown onto the silicon substrate via simple thermal evaporation process by using metallic zinc powder in the presence of oxygen at approximately 550 degrees C without the use of any metal catalysts or additives. The as-grown ZnO nanorods were characterized in terms of their structural and optical properties.

Temperature dependant structural and electrical properties of ZnO nanowire networks.

In this paper, we report a successful growth of zinc oxide nanowire networks by simple thermal evaporation process using metallic zinc powder in the presence of oxygen. The morphological investigations of the synthesized nanowire networks are conducted by using field emission scanning electron microscopy (FESEM) which reveals that the grown products are in high-density over the whole substrate surface and possessing nanowire networks like structures. The structural and compositional properties of the grown nanowire networks are analyzed by X-ray diffraction (XRD), transmission electron microscopy (TEM) and energy dispersive spectroscopy (EDS), respectively which confirm that the synthesized products are well-crystalline, with wurtzite hexagonal phase ZnO.

Ultra-high sensitive ammonia chemical sensor based on ZnO nanopencils.

This paper reports a very simple, reliable and facile methodology to fabricate ultra-high sensitive liquid ammonia chemical sensor using well-crystalline hexagonal-shaped ZnO nanopencils as an efficient electron mediator. A low-temperature facile hydrothermal technique was used to synthesize ZnO nanopencils. The synthesized nanopencils were characterized in detail in terms of their morphological, structural and optical properties which confirmed that the synthesized nanomaterial is well-crystalline, possessing wurtzite hexagonal phase and possess very good optical properties.

Large-scale synthesis of ZnO balls made of fluffy thin nanosheets by simple solution process: structural, optical and photocatalytic properties.

This paper reports a large-scale synthesis of ZnO balls made of fluffy thin ZnO nanosheets by simple solution process at low-temperature of 65±2°C. The synthesized ZnO structures were characterized in detail in terms of their morphological, structural, optical and photocatalytic properties. The detailed morphological characterizations, done by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM), confirmed that the synthesized products are ZnO balls which are made by accumulation of hundreds of thin ZnO nanosheets.

Utilization of ZnO nanocones for the photocatalytic degradation of acridine orange.

A facile aqueous solution process was used to synthesize well-crystalline ZnO nanocones at 60 degrees C by using zinc nitrate hexahydrate and sodium hydroxide. The morphological, structural and optical properties of the synthesized ZnO nanocones were investigated by using field emission scanning electron microscopy (FESEM) attached with energy dispersive spectroscopy (EDS), transmission electron microscopy (TEM) equipped with high-resolution (HRTEM), X-ray diffraction (XRD) pattern, Fourier transform infrared (FTIR) spectroscopy and UV-Vis. spectroscopy measurements.

Well-crystalline ZnO nanowire based field effect transistors (FETs).

Well-crystalline ZnO nanowires were grown on Si(100) via non-catalytic thermal evaporation process using metallic zinc powder in presence of oxygen. The detailed morphological characterizations by field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM) confirmed that the synthesized products are nanowires with the typical diameter and lengths of approximately 55 +/- 5 nm and several micrometers, respectively and are grown in high density over the silicon substrate. The detailed structural characterizations by high-resolution TEM and X-ray diffraction confirmed that the synthesized nanowires are well-crystalline and possessing wurtzite hexagonal phase.

Growth and properties of ultra-violet emitting aligned zinc oxide nanocones with hexagonal caps.

Ultraviolet-emitting, single-crystalline aligned zinc oxide (ZnO) nanocones with hexagonal caps were grown on silicon substrate via simple non-catalytic thermal evaporation process. High-purity metallic zinc powder and oxygen were used as source materials for zinc and oxygen, respectively. The detailed structural characterizations confirmed that the formed products are single-crystalline, possess a wurtzite hexagonal phase and grown along the c-axis direction.

Low-temperature growth and dye-sensitized solar cells applications of flower-shaped ZnO hexagonal nanorods.

Flower-shaped ZnO structures composed of hexagonal nanorods were grown in a large-quantity via simple aqueous solution process by using zinc nitrate as a source of zinc ions at low-temperature of approximately 85 degrees C. The as-grown flower-shaped ZnO structures composed of hexagonal nanorods were characterized in terms of their structural, optical and photovoltaic properties by using X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), selected area electron diffraction (SAED) pattern, FTIR, UV-Vis and Raman-scattering spectroscopy. The detailed structural investigations confirmed that the as-synthesized products are well-crystalline and possessing wurtzite hexagonal phase.

A novel method for preparing stoichiometric SnO(2) thin films at low temperature.

Tin oxide is a well known nonstoichiometric material with dual valency. The invariance of stoichiometry is very intriguing. As of today no report is available for preparing perfect stoichiometric tin oxide.

Hierarchical ZnO nanostructures: growth and optical properties.

Growth of hierarchical ZnO nanostructures composed of ZnO nanoneedles have been achieved via simple thermal evaporation process by using metallic zinc powder in the presence of oxygen at low temperature of 460 degrees C on silicon substrate without the use of any kind of metal catalysts or additives. It is confirmed by detailed structural studies that the as-grown hierarchical nanostructures are single crystalline with a wurtzite hexagonal phase and nanoneedles of these structures are grown along the c-axis in the [0001] direction. The Raman-scattering analysis substantiates a wurtzite hexagonal phase with a good crystal quality for the as-grown products.

Highly-sensitive cholesterol biosensor based on well-crystallized flower-shaped ZnO nanostructures.

This paper reports the fabrication of highly-sensitive cholesterol biosensor based on cholesterol oxidase (ChOx) immobilization on well-crystallized flower-shaped ZnO structures composed of perfectly hexagonal-shaped ZnO nanorods grown by low-temperature simple solution process. The fabricated cholesterol biosensors reported a very high and reproducible sensitivity of 61.7 microA microM(-1)cm(-2) with a response time less than 5s and detection limit (based on S/N ratio) of 0.