Crystal Architecture Research Articles

A Review on Bi2WO6-Based Materials for Photocatalytic CO2 Reduction.

Photocatalytic reduction of CO2 (PCR) technology offers the capacity to transmute solar energy into chemical energy through an eco-friendly and efficacious process, concurrently facilitating energy storage and carbon diminution, this innovation harbors significant potential for mitigating energy shortages and ameliorating environmental degradation. Bismuth tungstate (Bi2WO6) is distinguished by its robust visible light absorption and distinctive perovskite-type crystal architecture, rendering it highly efficiency in PCR. In recent years, numerous systematic strategies have been investigated for the synthesis and modification of Bi2WO6 to enhance its photocatalytic performance, aiming to achieve superior applications. This review provides a comprehensive review of the latest research progress on Bi2WO6 based materials in the field of photocatalysis. Firstly, outlining the fundamental principles, associated reaction mechanisms and reduction pathways of PCR. Then, the synthesis strategy of Bi2WO6-based materials is introduced for the regulation of its photocatalytic properties. Furthermore, accentuating the extant applications in CO2 reduction, including metal-Bi2WO6, semiconductor-Bi2WO6 and carbon-based Bi2WO6 composites etc. while concludes with an examination of the future landscape and challenges faced. This review hopes to serve as an effective reference for the continuous improvement and implementation of Bi2WO6-based photocatalysts in PCR.

A multi-computational and crystallographic investigation for the antibiotic mechanism of two 2,4-bis(4-methoxyphenamino)pyrimidines

2,4-bis(4-methoxyphenamino)pyrimidines are effective anti-bacterial against various bacteria. The compounds 1a and 1b displayed IC50 values of 3µM and 6.1µM, respectively, against Salmonella Typhimurium. The research aims to comprehensively understand the mechanisms of action of these compounds against bacteria using a diverse array of experimental and computational techniques. The findings from the single-crystal X-ray crystallographic investigation reveal several key insights. First, compounds 1a and 1b adopt distinct conformations of the same structure. Second, the amine-pyrimidine resonance is favored over the amine-methoxy aryl resonance. Third, H⸱⸱⸱H, O⸱⸱⸱H, and N⸱⸱⸱H interactions are the primary driver of molecular assembly. Lastly, Van der Waals and hydrophobic interactions significantly influence the crystal architecture and are conformation-dependent. Computational results suggest that, depending upon the molecular volume, both compounds can inhibit SseF with a marginal difference by stable binding with the same conformer observed in the solid state of 1a through hydrophobic interactions due to the presence of electron-rich phenyl rings. The compound 1b exhibited greater structural variability in the binding site compared to 1a, leading to lower stability. Moreover, the higher molecular volume of 1b, attributed to the methyl group, results in its comparatively lesser fitting in the SseF pore compared to 1a.

The role of photonic crystal based architectures on tailoring the laser induced fluorescence from green emitting cesium lead bromide nanocrystals

Researchers have long been fascinated by fluorescence and its potential to be boosted as it unlocks a treasure trove of promising applications. In this context, this experimental study investigates the amplification of laser induced fluorescence (LIF) emission from cesium lead bromide (CsPbBr3) perovskite nanocrystals (PNC) using two distinct all-polymer photonic crystal (PC) architectures made of poly 9-vinyl carbazole (PVK) and cellulose acetate (CA) as high and low refractive index (RI) layers, respectively. First structure is a photonic crystal micro cavity (PCMC) where PNC incorporated PVK (PNC:PVK) polymer matrix forms the defect layer sandwiched between two similar PCs. In the second structure, PNC:PVK composite itself functions as high RI layers within the PC. These two designs exploit different mechanisms to achieve fluorescence enhancement. The findings demonstrate the promise of simple, solution processed polymer PCs on applications demanding intensified fluorescence output and pave way to the development of flexible photonic devices capable of manipulating light emission.

Synthesis of Zn2+:LaMnO3 perovskites nanoparticles by facile co-precipitation approach: Physicochemical characteristics and supercapacitor application

This work has examined the impact of Zn2+ on the crystal architecture and electrochemical functionality of LaMnO3 perovskite nanoparticles. Crystalline parameters of the as-prepared samples were analyzed by X-ray Diffraction studies (XRD). Fourier transform infrared (FT-IR) measurements are utilized to detect the functional groups present in the sample. Raman spectroscopy technique was used to analyze the nature of the chemical bonds in the prepared material. The shape and elemental content of the produced nanomaterials were determined using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDAX). Brunauer-Emmett-Teller (BET) technique is used to study the porosity and surface area of the material. Electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge/discharge (GCD) is employed to study the surface resistivity, oxidation–reduction potential and super capacitance efficiency of the prepared electrode material.

Multi-Fano resonances by TCS and resonance-enhanced TES in hybrid photonic crystals for ultracompact sensing

This work introduces a novel hybrid photonic crystal (PC) architecture exploiting topologically multi-Fano resonances employing an inverted π-shape structure filled with a nontrivial PC flanked by M−shaped trivial PCs for ultracompact and high-sensitivity sensing, harnessing their immense potential for miniaturized sensing applications. Topological corner state (TCS) is formed in the structure. Moreover, a waveguide-branch resonator or a resonant ring for the topological edge state (TES) mode is formed to increase the Fano resonance. We demonstrate the existence of engineered quasi-bound multi-Fano resonances within this structure, exhibiting tunable quality factors exceeding 108 (ultrahigh Q) and a remarkable figure of merit (FOM), reaching 2.6×107RIU-1. By precisely controlling the nontrivial PC dimensions, we achieve exquisite control over the resonance’s Q factor and spectral line shape, revealing characteristics of quasi-bound states in the continuum (BICs). This hybrid architecture exhibits exceptional sensitivity to refractive index changes, with tunability ranging from 320 to 392 nm/RIU. Our work paves the way for a new paradigm in sensing, enabling the development of ultracompact on-chip nanophotonic devices with unprecedented sensitivity and control.

Influence of surfactants in nematic liquid crystal droplets

Liquid crystals in spherical droplets are highly sensitive to surfactants that control their orientation at interfaces. These molecules are widely used in optics. We fabricated 5CB liquid crystal droplets using SDS, CTAB, and DTAB surfactants at varying concentrations. We observed the transition from bipolar to radial at SDS concentration of 0.4 mM in 80 s, and from radial to bipolar at SDS concentration of 0.5 mM in 45 s. Surfactant concentration is the primary factor affecting liquid crystal droplet configuration, while headgroup, tail length, and architecture have minimal impact beyond the amount of absorbed surfactant in nematic liquid crystal droplets.

Supramolecular architectures in multicomponent crystals of imidazole-based drugs and trithiocyanuric acid.

The structures of three multicomponent crystals formed with imidazole-based drugs, namely metronidazole, ketoconazole and miconazole, in conjunction with trithiocyanuric acid are characterized. Each of the obtained adducts represents a different category of crystalline molecular forms: a cocrystal, a salt and a cocrystal of salt. The structural analysis revealed that in all cases, the N-H...N hydrogen bond is responsible for the formation of acid-base pairs, regardless of whether proton transfer occurs or not, and these molecular pairs are combined to form unique supramolecular motifs by centrosymmetric N-H...S interactions between acid molecules. The complex intermolecular forces acting in characteristic patterns are discussed from the geometric and energetic perspectives, involving Hirshfeld surface analysis, pairwise energy estimation, and natural bond orbital calculations.

Temperature-dependent transformation of decavanadate-type {V10O28}6- clusters into {V3O7}- layer structures mediated by 3-quinuclidinol as a structural templating agent: Crystal architectures and mechanism

In this study, two novel vanadate with different dimensions were prepared by hydrothermal synthesis using 3-quinuclidinol as the structural templating agent, namely, zero-dimensional decavanadate [(C7H14NO)6(V10O28)]·2H2O (1) and two-dimensional vanadate [C7H14NO][V3O7]·H2O (2). At a low reaction temperature of 373 K, only crystal 1 is produced. As the reaction temperature is increased in the range of 393–473 K, {V10O28}6- clusters can transform into {V3O7}- layers and the ratio of the transformation gradually increases, resulting in the formation of crystal 2. To our knowledge, this is the first study to achieve a controllable transformation of the vanadium-oxygen anion structure with different dimensions solely through adjusting the reaction temperature, without changing the reactant type and feed ratio. The transformation mechanism also was investigated. The results show that the transformation is caused by the redox reaction between 3-quinuclidinol with {V10O28}6- polyoxoanion. Moreover, 2 possesses a large layer spacing due to the large 3-quinuclidinol cations acting as the “pillar”, resulting in exhibiting good capacity performance (262.4 mAh g−1 at 0.1 A g−1) as the cathode material for aqueous zinc ion batteries. This study not only provides a viable approach for the temperature-tuned transformation of different dimensional vanadium-oxygen anion structures, but also proves that layered vanadate containing large cations are potential high-capacity cathode materials for AZIBs.

Crystal structure, molecular mechanics and In silico analyses of piperizine derivative against human mammary carcinoma cells inhibition.

In the present study, the single crystal of novel piperazine derivative4-(2, 3-chlorophenyl) piperazine-1-yl) (2-hydroxyphenyl) methanone (KDM) is grown by using the solvent evaporation method. The 3D structure of the molecule is confirmed by the single-crystal X-ray diffraction method. The study revealed that the molecular system is crystallized in the orthorhombic system with space group Pbca . The supramolecular crystal architecture establishes the stability of a compound via short contacts and halogen-hydrogen interactions. The Hirshfeld surface analysis were performed to evaluate the numerous intermolecular interactions based on the anisotropy of the topology. The Frontier molecular orbital (FMO) analysis and Molecular electrostatic potential (MEP) plots are investigated to understand the electronic structure properties of compounds using Density Functional Theory (DFT). In silico molecular docking, analysis is carried out to predict the best binding pose of the compound in the active site pocket of the BCl-XL/BAK protein-protein interface. Further, in vitro cytotoxicity studies against human breast cancer (MCF-7) cell lines of similarly designed piperazine-based derivatives showed prominent results. The results of the current study revealed that the compounds under investigation possess potential anti-cancer properties.

Photonic Crystal Structures for Photovoltaic Applications.

Photonic crystals are artificial structures with a spatial periodicity of dielectric permittivity on the wavelength scale. This feature results in a spectral region over which no light can propagate within such a material, known as the photonic band gap (PBG). It leads to a unique interaction between light and matter. A photonic crystal can redirect, concentrate, or even trap incident light. Different materials (dielectrics, semiconductors, metals, polymers, etc.) and 1D, 2D, and 3D architectures (layers, inverse opal, woodpile, etc.) of photonic crystals enable great flexibility in designing the optical response of the material. This opens an extensive range of applications, including photovoltaics. Photonic crystals can be used as anti-reflective and light-trapping surfaces, back reflectors, spectrum splitters, absorption enhancers, radiation coolers, or electron transport layers. This paper presents an overview of the developments and trends in designing photonic structures for different photovoltaic applications.

In situ and Real‐time Monitoring the Chemical and Thermal Evolution of Lithium‐ion Batteries with Single‐crystalline Ni‐rich Layered Oxide Cathode

AbstractHigh‐capacity Ni‐rich layered oxides are promising cathode materials for fabrication of lithium‐ion batteries (LIBs) with high energy density. However, thermal runaway of LIBs with these cathodes leads to great safety concerns. In this study, single crystalline LiNi0.9Co0.05Mn0.05O2 (NCM‐SC) has been prepared and a flexible optical fiber was buried inside the pouch‐type LIBs with NCM‐SC cathode to in situ study its real‐time temperature evolution during charge/discharge process. NCM‐SC exhibits an enhanced Li+ ions transportation efficiency and electrode reaction kinetics, which can effectively reduce the generation of polarization heat and mitigate the internal temperature rise of the pouch‐type battery. Meanwhile, solid‐electrolyte interface (SEI) film decomposition and gas accumulation are effectively alleviated, due to the enhanced thermal stability of SEI film formed on NCM‐SC. Moreover, the single crystal architecture can effectively retard layered to spinal and rock‐salt phase transition, mitigate the crack formation and structural collapse. Consequently, NCM‐SC exhibits an excellent electrochemical performance and enhanced thermal stability.

In situ and Real-time Monitoring the Chemical and Thermal Evolution of Lithium-ion Batteries with Single-crystalline Ni-rich Layered Oxide Cathode.

High-capacity Ni-rich layered oxides are promising cathode materials for fabrication of lithium-ion batteries (LIBs) with high energy density. However, thermal runaway of LIBs with these cathodes leads to great safety concerns. In this study, single crystalline LiNi0.9Co0.05Mn0.05O2 (NCM-SC) has been prepared and a flexible optical fiber was buried inside the pouch-type LIBs with NCM-SC cathode to in situ study its real-time temperature evolution during charge/discharge process. NCM-SC exhibits an enhanced Li+ ions transportation efficiency and electrode reaction kinetics, which can effectively reduce the generation of polarization heat and mitigate the internal temperature rise of the pouch-type battery. Meanwhile, solid-electrolyte interface (SEI) film decomposition and gas accumulation are effectively alleviated, due to the enhanced thermal stability of SEI film formed on NCM-SC. Moreover, the single crystal architecture can effectively retard layered to spinal and rock-salt phase transition, mitigate the crack formation and structural collapse. Consequently, NCM-SC exhibits an excellent electrochemical performance and enhanced thermal stability.

The elementary reactions for incorporation into crystals

The growth rates of crystals are largely dictated by the chemical reaction between solute and kinks, in which a solute molecule severs its bonds with the solvent and establishes new bonds with the kink. Details on this sequence of bond breaking and rebuilding remain poorly understood. To elucidate the reaction at the kinks we employ four solvents with distinct functionalities as reporters on the microscopic structures and their dynamics along the pathway into a kink. We combine time-resolved in situ atomic force microscopy and x-ray and optical methods with molecular dynamics simulations. We demonstrate that in all four solvents the solute, etioporphyrin I, molecules reach the steps directly from the solution; this finding identifies the measured rate constant for step growth as the rate constant of the reaction between a solute molecule and a kink. We show that the binding of a solute molecule to a kink divides into two elementary reactions. First, the incoming solute molecule sheds a fraction of its solvent shell and attaches to molecules from the kink by bonds distinct from those in its fully incorporated state. In the second step, the solute breaks these initial bonds and relocates to the kink. The strength of the preliminary bonds with the kink determines the free energy barrier for incorporation into a kink. The presence of an intermediate state, whose stability is controlled by solvents and additives, may illuminate how minor solution components guide the construction of elaborate crystal architectures in nature and the search for solution compositions that suppress undesirable or accelerate favored crystallization in industry.

Evolution of Microstructure and Mechanical Properties of Novel Al-Mg-Mn-Ag-Cr-Zr Alloy

In order to reinforce the mechanism of Ag in 5xxx aluminum alloys with low magnesium, research on the microstructure and mechanical properties of an Al-Mg-Mn-Ag-Cr-Zr alloy was conducted using optical microscopy (OM), scanning electron microscopy (SEM), transmission electron microscopy (TEM), hardness measurement, and tensile testing. The as-cast microscopic structure of the alloy comprises the Al6(Mn, Fe) phase and the T-Mg32(Al, Ag)49 phase. Changes in the characteristics of the investigated alloy were clear during the aging process. Based on the findings obtained from TEM and SAED analysis, it was evident that the predominant strengthening phase during the peak-aged stage is the β″ phase, observed when the alloy is aged for 24 h at 160 °C. The β″ phase had a L12-type crystal lattice architecture and presented a completely coherent relevance with the Al-matrix. The lattice parameter, a, of the β″ phase was 0.408 nm. The mechanical properties of the peak-aged alloy increased greatly as compared to the as-quenched alloy. The tensile strength exhibited a rise from 410 MPa to 449 MPa, representing a 9.5% increase, while the yield strength demonstrated an increase from 185 MPa to 273 MPa, indicating a significant enhancement of 47.5%. The method used in the present study has solved the problem of 5xxx aluminum alloys not being heat treatable for strengthening to a significant degree, considerably improving the alloy strength. In addition, new methods and foundations for exploiting new-type Al-Mg based alloys and developing high-strength aluminum alloys are provided in this study.

The influence of azide and imidazole on the properties of Mn- and Cd-based networks: conductivity and nonlinear phenomena

We report a study on a family of four new Mn- and Cd-azide-imidazolate-based compounds with various crystal architectures.

Facile synthesis and photophysical properties of combustion derived Dy3+doped Ca9La(PO4)7 nanophosphors for advanced solid-state lighting applications

Globally, the energy consumption has accelerated, which has driven the research to increase sustainable energy sources. In this context, this is the first report on the exploration of the structural and photometric aspects of Dy3+ doped Ca9La(PO4)7 i.e., CLP: Dy3+ nanophosphors for designing WLEDs economically. Herein, the solution combustion method was utilized for fabricating the desired nanophosphor, thereafter their morphological behavior, and crystallite size were studied in detail via X-ray diffraction, scanning electron microscopy (SEM) and high-resolution transmission electron microscopy (HRTEM) techniques which confirmed the rhombohedral crystal architecture with R3c space group affirming the potential of the fabricated nanomaterials in optoelectronics. CLP: Dy3+nanophosphors depicted reproducible emission spectra with peaks at 4F9/2 → 6H13/2, 15/2 attributed to intra-configurational transitions of Dy3+ ions. The increasing dopant concentration beyond 20 mol % reduced the intensity of emission peaks which could be ascribed to the dipole–dipole interactions of the neighboring ions. The optical band gap of 5.38 eV derived via Kubelka-Munk relations established their role in semiconductors. Moreover, their Commission international de I’eclairge (CIE) chromaticity coordinates were studied in detail to reveal the emission color with color purity and Correlated Color Temperature (CCT) values. All the results favored and exemplified the incredible role of CLP: Dy3+ nanophosphors for emerging future prospects in advanced optoelectronic technology.

Implementing Logic Gates by DNA Crystal Engineering.

DNA self-assembly computation is attractive for its potential to perform massively parallel information processing at the molecular level while at the same time maintaining its natural biocompatibility. It has been extensively studied at the individual molecule level, but not as much as ensembles in 3D. Here, the feasibility of implementing logic gates, the basic computation operations, in large ensembles: macroscopic, engineered 3D DNA crystals is demonstrated. The building blocks are the recently developed DNA double crossover-like (DXL) motifs. They can associate with each other via sticky-end cohesion. Common logic gates are realized by encoding the inputs within the sticky ends of the motifs. The outputs are demonstrated through the formation of macroscopic crystals that can be easily observed. This study points to a new direction of construction of complex 3D crystal architectures and DNA-based biosensors with easy readouts.

Halogen Bonding Assembles Anion···Anion Architectures in Non-centrosymmetric Iodate and Bromate Crystals.

Single crystal X-ray diffraction of iodate and bromate salts shows that the I and Br atoms in IO3- and BrO3- anions form short and linear O-I/Br···O contacts with the O atoms of nearby anions. Noncentrosymmetric systems are formed wherein anions are orderly aligned into supramolecular 1D and 2D networks. Theoretical evidences, namely the outcome of QTAIM and NCIplot studies, prove the attractive nature of these contacts and the ability of iodate and bromate anions to act as robust HaB donors. The HaB is proposed as a general and effective assisting tool to control the architecture of acentric iodate salts.

Analysis of the phases and functions of the various compounds of calcium sulfoaluminate cement after exposure to high temperature

High temperature (HT) in-situ XRD method was adopted to investigate the calcium sulfoaluminate cement (CSA) or C4A3$ crystal architecture as well as its phases when passing through the temperature range of 20° to 70 °C. We examined the particle size analysis of the CSA ground powder when heated to different temperature (e.g., 35, 50, and 70 °C) in correlation with the HT X-ray diffraction (HT XRD) pattern as well with the compressive strength. The particle size of the lattice parameters increased during heating. The architecture transformation phase of the CSA took place at 50 °C. The transformation of the crystal cubic structure phase of the C4A3$ when passing from orthogonal to cubic space group was unstable with more heating (70 °C) and was adjustable. The C4A3$ compound's orthogonal and cubic crystal structures were clearly identified. The crystal structures were found to be responsible for the dehydration that occurred as the temperature rose and also for the decrease in compressive strength. The obtained final products of the C4A3$ were in cubic and orthogonal forms. The exothermic form of the C4A3$ was mostly observed at 20 °C and at 35 °C. The AFt and AFm crystal structure framework was constituted of AlO6 (in octahedral form) and AlO4 (in tetrahedral form).

Fisk Memorial Chapel and the HBCU Architecture of Black Nonviolent Protest

Women in Higher EducationVolume 32, Issue 6 p. 11-15 HBCU Campuses Fisk Memorial Chapel and the HBCU Architecture of Black Nonviolent Protest Crystal A. de Gregory Ph.D., Crystal A. de Gregory Ph.D.Search for more papers by this author Crystal A. de Gregory Ph.D., Crystal A. de Gregory Ph.D.Search for more papers by this author First published: 21 June 2023 https://doi.org/10.1002/whe.21288Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL No abstract is available for this article. Volume32, Issue6June 2023Pages 11-15 RelatedInformation