Solid State Reaction Research Papers (original) (raw)

The evolution of microstructure of Ni and NaCl mixtures formed by mechanochemical reaction and mechanical milling has been studied using X-ray diffraction, electron microscopy and magnetic measurements. Separate nano-sized Ni particles... more

The evolution of microstructure of Ni and NaCl mixtures formed by mechanochemical reaction and mechanical milling has been studied using X-ray diffraction, electron microscopy and magnetic measurements. Separate nano-sized Ni particles were formed by continuous solid-state reaction of NiCl2 + 2Na during mechanical milling. Further milling resulted in the growth of clustered particles due to inter-particle welding during collision events. On the other hand, milling of micron-sized Ni and NaCl powders resulted in a layered particle morphology and continuous decrease in particle size with increasing milling time.

Hydroxyapatite (HAp) is a potential material for various biomedical applications. In the present study, an attempt has been made to synthesize this material using simpler and cheaper method of solid-state-reaction process. Samples were... more

Hydroxyapatite (HAp) is a potential material for various biomedical applications. In the present study, an attempt has been made to synthesize this material using simpler and cheaper method of solid-state-reaction process. Samples were prepared by mixing the ingredients and ...

Hybrid nanocomposites of Cu 2 O−(R)TiO 2 , CuO−(R)TiO 2 , and Cu 3 TiO 4 −(R)TiO 2 (where R represents the rutile phase of TiO 2) nanopowders (NPs) were produced via solid state reaction followed by 20 h of ball milling; their... more

Hybrid nanocomposites of Cu 2 O−(R)TiO 2 , CuO−(R)TiO 2 , and Cu 3 TiO 4 −(R)TiO 2 (where R represents the rutile phase of TiO 2) nanopowders (NPs) were produced via solid state reaction followed by 20 h of ball milling; their photocatalytic activities were evaluated for methylene blue (MB) degradation under visible light intensity (∼65 mW/ cm 2) and compared to Degussa P25 under both ultraviolet (UV) and visible light irradiations. The highest MB degradation rate under the visible light irradiation was observed to be 0.271 ± 0.010 h −1 for Cu 2 O−(R)TiO 2 NPs, which was 2.5 times higher than that of P25, while under UV illumination both the Cu 2 O−(R)TiO 2 and Cu 3 TiO 4 − (R)TiO 2 NPs were slightly less active than that of the P25, and CuO−(R)TiO 2 was the least active among all. The solar energy conversion performance of the Cu x O−(R)TiO 2 NPs was observed to be controlled by the applied potentials. The highest stable cathodic photocurrent density (6.3 μA/cm 2) was observed for Cu 2 O−(R)TiO 2 NPs at a low negative bias voltage (−0.3 V vs Ag/AgCl, 3 M KCl) and under the solar simulator (AM 1.5G). This method to design multifunctional visible-light-active metal oxides is simple and scalable and has the potential to prepare other efficient photocatalysts for solar energy conversion.

Nanostructured Fe3O4 nanoparticles were prepared by a simple sonication assisted co-precipitation method. Transmission electron microscopy, X-ray diffraction and BET surface area analysis confirmed the formation of ∼20 nm crystallites... more

Nanostructured Fe3O4 nanoparticles were prepared by a simple sonication assisted co-precipitation method. Transmission electron microscopy, X-ray diffraction and BET surface area analysis confirmed the formation of ∼20 nm crystallites that constitute ∼200 nm nanoclusters. Galvanostatic charge–discharge cycling of the Fe3O4 nanoaprticles in half cell configuration with Li at 100 mA g−1 current density exhibited specific reversible capacity of 1000 mAh g−1. The cells showed stability at high current charge–discharge rates of 4000 mA g−1 and very good capacity retention up to 200 cycles. After multiple high current cycling regimes, the cell always recovered to full reversible capacity of ∼1000 mAh g−1 at 0.1 C rate.• A simple and inexpensive ultrasonic assisted co-precipitation route has been followed to make monodisperse Fe3O4 nanoparticles. • Anodes made from the Fe3O4 nanoparticles exhibit specific reversible capacity of ∼1000 mAh g−1. • The anodes could operate at a current density from 100 to 4000 mA gm−1 with coulombic efficiency of almost 100%. • The anodes showed excellent cyclic stability for at least 200 cycles without capacity fade, and returned to specific capacity of 1000 mAh gm−1 at 0.1 C after multiple high current charge–discharge cycles.

In this work, we report the Rietveld refinement, microstructure, conductivity and impedance properties of Ba[Zr0.25Ti0.75]O3 ceramic synthesized by solid state reaction. This ceramic was characterized by X-ray diffraction, Rietveld... more

In this work, we report the Rietveld refinement, microstructure, conductivity and impedance properties of Ba[Zr0.25Ti0.75]O3 ceramic synthesized by solid state reaction. This ceramic was characterized by X-ray diffraction, Rietveld refinement, scanning electron microscopy and energy dispersive X-ray spectrometry. Impedance spectroscopy analyses reveals a non-Debye relaxation phenomenon being its relaxation frequency moving toward to positive side with increase of temperature. A significant shift in impedance loss peaks toward higher frequency side indicates conduction in material and favoring the long range motion of mobile charge carriers. The frequency dependent ac conductivity at different temperatures indicates that the conduction process is thermally activated. The variation of dc conductivity exhibited a negative temperature coefficient of resistance behavior. The ac conductivity data are used to evaluate the density of states at Fermi level and activation energy of this ceramic. The dc electrical and thermal conductivities of grain and grain boundary have been discussed.► Rietveld refinement of Ba[Zr0.25Ti0.75]O3 ceramic and modeling of clusters in cubic structure. ► Investigation of microstructure of Ba[Zr0.25Ti0.75]O3 ceramic with explanations more detailed. ► Impedance properties of Ba[Zr0.25Ti0.75]O3 ceramic in various temperatures. ► Conduction mechanism for grain and grain boundaries of Ba[Zr0.25Ti0.75]O3 ceramic. ► Electronic thermal conductivity for grain and grain boundaries of Ba[Zr0.25Ti0.75]O3 ceramic.

Double perovskite structure with composition of Sr2Mg1-xMnxMoO6 (SMMMO) and Sr2Mg1-xFexMoO6 (SMFMO) for anode materials in solid oxide fuel cell have been synthesized by means of solid state reaction and sol gel method, respectively.... more

Double perovskite structure with composition of Sr2Mg1-xMnxMoO6 (SMMMO) and Sr2Mg1-xFexMoO6 (SMFMO) for anode materials in solid oxide fuel cell have been synthesized by means of solid state reaction and sol gel method, respectively. Crystal structure of those materials were characterized by X-ray diffraction technique and refined using Rietveld method implemented in the Rietica program and their conductivity were determined by DC conductivity measurement technique. The higher Mn concentration the lower the cell volume of SMMO, whilst for SMFO the higher Fe content the larger the cell. For SMMO the ionic conductivity tends to increase with increased Mn, whilst for SMFMO conductivity decreases as Fe concentration increases.

A novel red-emission phosphor of Eu3+-doped tungstate was prepared at 950°C by a modified solid-state reaction. Photoluminescence (PL) results showed that the phosphor can be efficiently excited by irradiation at wavelengths in the... more

A novel red-emission phosphor of Eu3+-doped tungstate was prepared at 950°C by a modified solid-state reaction. Photoluminescence (PL) results showed that the phosphor can be efficiently excited by irradiation at wavelengths in the near-UV and blue regions of the spectrum. The material has potential application as the fluorescent material for ultraviolet light-emitting diodes (UV-LEDs). The crystallization and particle sizes of the phosphor have been investigated by using powder X-ray diffraction (XRD) and transmission electron microscopy (TEM).