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Nanocrystalline CO₃O₄ particles were successfully synthesized by hydrothermal method under pulsed magnetic field. The effect of magnetic field and aging time on the morphology and microstructure were examined. Different morphologies were observed from SEM images for the samples fabricated with or without pulsed magnetic field. The pulsed magnetic field made CO₃O₄ sphere compact and more smooth surface. The hollow sphere morphology and refined grain of CO₃O₄ were formed after aging process.

Amorphous zirconium oxide (a-ZrO₂) thin films were prepared onto fuzzed quartz substrates by ion beam sputtering deposition (IBSD) method in (Ar +O₂) gas mixture. Optical parameters of the films were evaluated by laser ellipsometry (λ = 632.8 nm) and optical transmission measurements. Structural parameters were studied by XRD measurements. Variation of refractive index and film thickness have been defined as a function of time of high-temperature annealing at T = 900°C. Formation of monoclinic zirconium oxide (m-ZrO₂) nanocrystals with diameter of ~60 nm embedded into a-ZrO₂ matrix has been found by XRD analysis after long-time annealing.

A typical nitrogen doped spherical SiC nanocrystal with a diameter of 1.2 nm (Si₄₃C₄₄H₇₆) using linear combination atomic orbital (LCAO) in combination with pseudopotential density functional calculation have been studied. Our selected SiC nanocrystal has been modeled taking all the cubic bulk SiC atoms contained within a sphere of a given radius and terminating the surface dangling bonds with hydrogen atoms. We have examined nine possible situations in which nitrogen has a high probability for replacement in the lattice or placed between atoms in the nanocrystal. We have found that the silicone can substitute with a nitrogen atom in each layer as the constructed nanocrystals remain thermodynamically stable. Also the nitrogen atom can be placed between the free atomic spaces as the more thermodynamically stable position of the nitrogen is between the topmost layers. Also the optical absorption and refractive index energy dispersions of the pure and various stable doped SiC nanocrystals were studied.

LiFePO₄ nanocrystals were synthesized in various polyol media without any further post-heat treatment. The LiFePO₄ samples synthesized using three different polyol media namely, diethylene glycol (DEG), triethylene glycol (TEG), and tetraethylene glycol (TTEG), exhibited plate and rod-shaped structures with average sizes of 50–500 nm. The X-ray diffraction (XRD) patterns were indexed on the basis of an olivine structure (space group: Pnma). The samples prepared in DEG, TEG, and TTEG polyol media showed reversible capacities of 123, 155, and 166 mAh/g, respectively, at current density of 0.1 mA/cm² with no capacity fading and exhibited excellent capacity retention up to the 50th cycle. In particular, the samples showed excellent performances at high rates of 30 and 60 C with high capacity retention. It is assumed that the nanometer size materials (~50 nm) possessing a highly crystalline nature may generate improved performance at high rate current densities.

A novel procedure to fabricate nanoarchitectures of crystalline titania hollow shells was developed by using assembled latex particles as templates. Latex particles were assembled on the surface of solid substrates and covered with ultrathin titania films by the surface sol–gel process. When the titania-covered latex particle was subjected to oxygen plasma treatment, hollow titania spheres were formed at the original site of particle deposition. Following calcination of the amorphous, titania hollow shells induced their crystallization to titania nanocrystals (anatase).

Monodispersed DAST nanocrystals have almost been successfully fabricated by means of the inverse reprecipitation method. By employing AC electric field, high electric field of above ca. 1.0 kVcm^-1 could be applied to polar DAST nanocrystals dispersed in decahydronaphthalene, so as to avoid electrophoresis of nanocrystals under DC electric field. The response of DAST nanocrystal dispersion to applied AC electric field was analyzed phenomenologically by fitting Langevin function, which provided a large permanent dipole moment of DAST nanocrystal. In addition, we have succeeded in in situ observation of AC electric-field-induced orientational motion of DAST crystals by using an optical microscope. The present DAST nanocrystal dispersion system will be expected as an optical device like display monitor.

Photoluminescent properties of CdSe/ZnS nanocrystals (quantum dots, QDs) in complexes with elongated gold nanoparticles was found to be dependent on the effective refractive index of the medium. It has been experimentally shown that changes in the refractive index make possible to increase the photoluminescence intensity by several times.

Nanostructured LiFePO₄ is appealing cathode material for rechargeable lithium batteries. Herein, however, we report the intriguing anode properties of carbon coated LiFePO₄ nanocrystals. In the potential range of 0–3.0 V, the LiFePO₄ nanocrystal electrodes afford high reversible capacity of 373 mAhg${}^{-1}$ at a current rate of 0.05 Ag${}^{-1}$ and retains 239 mAhg${}^{-1}$ at a much higher rate of 1.25 Ag${}^{-1}$. In addition, it is capable of sustaining 1000 cycles at 1.25 Ag${}^{-1}$ without any capacity fading. Such superior properties indicate that nanostructured LiFePO₄ could also be promising anode for rechargeable battery applications.

PbS nanocrystals with octahedron shape are synthesized by a low temperature approach with presence of cation/anion surfactants in aqueous solution. CdS quantum dot sensitized solar cells (QDSSCs) based on these novel octahedron shaped PbS counter electrodes (CEs) are fabricated for the first time, achieving PCE of 1.54%. It is observed that the octahedron shaped PbS CE shows higher electrocatalytic activity compared with the Pt CE, indicating that the PbS nanocrystals with a uniformly distributed size is a superior candidate as CEs for QDSSCs application. This work may provide new route for preparing PbS from aqueous solvent medium through a simple synthesis route.

Going down the particle size to nanodomain opens up innovative allies to expedite the physical and chemical properties of materials, and in turn, facilitates the manipulation of their catalytic propensity. Herein, we provide a succinct perspective of the wide spectrum of nanoparticles (NPs) in catalysis highlighting the underlying chemistry of different aspects, the introspective thread connecting them, and the ways to devise operando algorithms for exploiting such inter-connected systems. Following an introductory section discussing the generic miens of NPs, we went on to discuss the role of nanocrystals, especially various crystal facets and morphological anomalies in catalysis. The electronic shuttling involved in these catalysis vis-à-vis surface plasmon effect, Mott–Schottky contact, and Z-scheme systems, all in the nanodomain, was then explained. Following this, we introduced the concept of “Soft Matter” and “Active Matter”, essentially the ones exploiting previously discussed chemistry, and explained the role of their in situ morphological precedence and stimuli-induced motility in catalysis. Finally, the emerging concept of Operando Systems Chemistry Algorithm (OSCA) was instituted discussing the devising strategies of tandem compartmentalized chemical arrays as individual algorithm analogs to sequentially impact the properties of aforementioned soft and active matters for targeted catalytic assays.