Experimental and theoretical study to explain the morphology of CaMoO 4 crystals

Abstract

Ag 2 CrO 4 microcrystals were synthesized Q3 using the co-precipitation method. These microcrystals were characterized through X-ray diffraction (XRD) with Rietveld analysis, field-emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM) with energy-dispersive spectroscopy (EDS), micro-Raman (MR). XRD patterns and Rietveld refinement data showed that the material exhibits an orthorhombic structure without any deleterious phases. FE-SEM and TEM micrographs revealed the morphology and the growth of Ag nanoparticles on Ag 2 CrO 4 microcrystals during electron beam irradiation. These events were directly monitored in real-time. Their optical properties were investigated using ultraviolet-visible (UV-vis) diffuse reflectance spectroscopy that allowed the calculation of the optical band gap energy. Theoretical analyses based on the density functional theory level indicate that the incorporation of electrons is responsible for structural modifications and formation of defects on the [AgO 6 ] and [AgO 4 ] clusters, generating ideal conditions for the growth of Ag nanoparticles.

The role of the Tm3+ concentration on CaMoO4 properties processed by microwave hydrothermal under stirring condition

“…The observed diffraction peaks can be indexed to the CaMoO 4 scheelite type (tetragonal structure) with the space group I4 1/a and are in full agreement with the standard data (JCPDS card no. 29‐0351) 52,53 . The additional peaks were observed only in XRD pattern corresponding to the CMO:Tm‐12 sample, and they occur at 2θ = 7.8°, 23.0°, and 35.5° (Figure 1G).…”

“…29-0351). 52,53 The additional peaks were observed only in XRD pattern corresponding to the CMO:Tm-12 sample, and they occur at 2θ = 7.8°, 23.0°, and 35.5° (Figure 1G). These peaks are predicted theoretically through simulations for a compressed and distorted CaMoO 4 tetragonal structure.…”

Reading at exposed surfaces: theoretical insights into photocatalytic activity of ZnWO4

“…Even, at biological level, the invention of DNA origami has deepened the understanding of how molecules could interact with each other in a complex self-assembly process and has accelerated the engineering of molecular systems with custom-designed structures and programmable behaviors [153][154][155][156][157][158][159] . In solid state, the concept of crystal origami has been introduced toward the rational design of surface structures of micro-and nano-crystallites 144,160,161 .…”

Fabricated Flexible Composite for a UV-LED Color Filter and Anti-Counterfeiting Application of Calcium Molybdate Phosphor Synthesized at Room Temperature

“…Among the work on phosphors with good color purity and high luminous efficiency, research intended to facilitate the use of molybdate phosphors doped with rare-earth ions in various applications, such as light-emitting devices, lasers, scintillation materials, optical fibers, catalysts, and displays, is attracting attention [ 6 , 7 , 8 ]. Specifically, calcium molybdate (CaMoO 4 ) can be used in a wide range of applications due to its stable physicochemical properties and the low absorption critical energy of its scheelite structure [ 9 , 10 ]. Kim et al produced CaMoO 4 :Eu 3+ with Na + phosphors with a diameter of 5 nm from a TOA-MoO 4 complex with calcium, europium, and sodium-oleate (Ca, Eu, and Na-oleate) mixed in toluene using a solvothermal synthesis method, and suggested that the strongest red emission occurred in Ca 0.58 MoO 4 : 0.21 Eu 3+ , with 0.21 Na + nanophosphors synthesized at 120 °C [ 11 ].…”