Synthesis Of Inorganic Materials Research Articles

Synthesis, properties, and applications of 2D amorphous inorganic materials

In the last decade, the research on two-dimensional (2D) materials has drawn a lot of interest from the aspects of both fundamental study and practical application. The atomic-scale thickness and unique layered structure make the materials in this family exhibit a number of distinct optical and electrical properties from their bulk counterparts. Previous studies have mainly focused on the crystalline 2D candidates. Recently, the highly disordered form of 2D materials, such as amorphous 2D materials, is emerging to attract increasing attention since it has shown great potential for applications in various fields. Here, we give a perspective on the recent progress in 2D amorphous inorganic materials. First, the synthesis techniques and process of 2D amorphous materials and their hybrid structure are given. Furthermore, the intriguing properties and applications in electronic, optoelectronic, and energy fields from typical 2D amorphous inorganic materials, including amorphous graphene, amorphous molybdenum disulfide, amorphous boron nitride, and amorphous black phosphorus, are introduced. Furthermore, the advantages and mechanisms of 2D amorphous materials are illustrated, pointing out the application scope of this material group. Finally, the underlying challenges of amorphous inorganic 2D materials are briefly outlined and some future outlooks are suggested.

Metals by Micro-Scale Additive Manufacturing: Comparison of Microstructure and Mechanical Properties.

Many emerging applications in microscale engineering rely on the fabrication of 3D architectures in inorganic materials. Small-scale additive manufacturing (AM) aspires to provide flexible and facile access to these geometries. Yet, the synthesis of device-grade inorganic materials is still a key challenge toward the implementation of AM in microfabrication. Here, a comprehensive overview of the microstructural and mechanical properties of metals fabricated by most state-of-the-art AM methods that offer a spatial resolution ≤10 μm is presented. Standardized sets of samples are studied by cross-sectional electron microscopy, nanoindentation, and microcompression. It is shown that current microscale AM techniques synthesize metals with a wide range of microstructures and elastic and plastic properties, including materials of dense and crystalline microstructure with excellent mechanical properties that compare well to those of thin-film nanocrystalline materials. The large variation in materials' performance can be related to the individual microstructure, which in turn is coupled to the various physico-chemical principles exploited by the different printing methods. The study provides practical guidelines for users of small-scale additive methods and establishes a baseline for the future optimization of the properties of printed metallic objects-a significant step toward the potential establishment of AM techniques in microfabrication.

The interplay between thermodynamics and kinetics in the solid-state synthesis of layered oxides.

In the synthesis of inorganic materials, reactions often yield non-equilibrium kinetic byproducts instead of the thermodynamic equilibrium phase. Understanding the competition between thermodynamics and kinetics is a fundamental step towards the rational synthesis of target materials. Here, we use in situ synchrotron X-ray diffraction to investigate the multistage crystallization pathways of the important two-layer (P2) sodium oxides Na0.67MO2 (M = Co, Mn). We observe a series of fast non-equilibrium phase transformations through metastable three-layer O3, O3' and P3 phases before formation of the equilibrium two-layer P2 polymorph. We present a theoretical framework to rationalize the observed phase progression, demonstrating that even though P2 is the equilibrium phase, compositionally unconstrained reactions between powder precursors favour the formation of non-equilibrium three-layered intermediates. These insights can guide the choice of precursors and parameters employed in the solid-state synthesis of ceramic materials, and constitutes a step forward in unravelling the complex interplay between thermodynamics and kinetics during materials synthesis.

Lignin-Inorganic Interfaces: Chemistry and Applications from Adsorbents to Catalysts and Energy Storage Materials.

Lignin is one the most fascinating natural polymers due to its complex aromatic‐aliphatic structure. Phenolic hydroxyl and carboxyl groups along with other functional groups provide technical lignins with reactivity and amphiphilic character. Many different lignins have been used as functional agents to facilitate the synthesis and stabilization of inorganic materials. Herein, the use of lignin in the synthesis and chemistry of inorganic materials in selected applications with relevance to sustainable energy and environmental fields is reviewed. In essence, the combination of lignin and inorganic materials creates an interface between soft and hard materials. In many cases it is either this interface or the external lignin surface that provides functionality to the hybrid and composite materials. This Minireview closes with an overview on future directions for this research field that bridges inorganic and lignin materials for a more sustainable future.

BASES OF DEVELOPMENT OF TECHNOLOGIES OF SYNTHESIS OF OXIDE MATERIALS IN BIG SOLAR FURNACE (PARKENT)

The advantages of synthesis of complex oxide compounds by solar energy, the possibility of obtaining highly textured nano materials are shown. The development of heliomaterial science, aimed at the synthesis of new materials, is inextricably linked with the use of effective optical energy systems. On the example of obtaining superconducting materials of nominal composition Bi1.7Pb0.3Sr2Ca(n-1)CunOy (n = 3-20), optimization of the parameters of the optical-energy system of the Big Solar Furnace (Parkent) is shown. The ideology of developing heliotechnology for the synthesis of inorganic materials in a solar furnace is presented. The properties of a superconducting material of nominal Bi1.7Pb0.3Sr2Ca(n1)CunOy (n = 3-20) obtained according to the proposed methodology for the synthesis of materials in a solar furnace are presented.

Recent Advances in Improving Phase Stability of Perovskite Solar Cells

AbstractOrganic–inorganic hybrid perovskite solar cells (PSCs) have demonstrated high efficiency and improved stability, which shows promising potential for commercialization. However, among all challenges, the material and device instability of the methylammonium lead iodide (MAPbI3) absorber are regarded as serious obstacles to the future development of devices for long‐term operation. Compared with conventional MAPbI3, formamidinium lead iodide (FAPbI3) and cesium lead iodide (CsPbI3) have attracted more attention due to their superior thermal stability. Due to their undesirable tolerant factor, however, these materials suffer from poor phase stability, which is worthy of careful investigation. This perspective highlights the recent progress on the phase stabilization of FAPbI3 and inorganic CsPbI3 materials with emphasis on the fundamental understanding of the origin of phase instability. In addition, strategies to fabricate corresponding devices toward high‐efficiency and long‐lifetime are discussed. This review sheds light onto the design and synthesis of FAPbI3 and inorganic CsPbI3 perovskite materials. In the end, the potential of FAPbI3 and inorganic CsPbI3 perovskite materials as stable absorbers is discussed, which promotes the development of corresponding solar cells and other optoelectronic devices for practical applications.

Sustainable approach to almond skin mediated synthesis of tunable selenium microstructures for coating cotton fabric to impart specific antibacterial activity

Currently, the synthesis of nanostructured inorganic materials with tunable morphology is still a great challenge. In this study, almond skin extract was employed for the biogenic synthesis of selenium nanoparticles with tunable morphologies such as rods and brooms. The effects of various synthesis parameters on morphologies were investigated using UV–Visible spectroscopy and scanning electron microscopy (SEM) which indicated that selenium brooms (SeBrs) were best synthesized using almond skin extract and optimized conditions of SeO2, ascorbic acid, pH, incubation temperature and time. Based on these results, the mechanism of SeBrs synthesis is proposed as having involved four stages such as nucleation, self-assembly, Ostwald ripening, and decomposition. Further, the test of antibacterial activity together with minimum inhibitory concentrations and minimum bactericidal concentrations indicated the selective, specific and good activity against B. subtilis. In addition, in situ coating of SeBrs on cotton fabric and its investigation by SEM demonstrated successful coating. Evident from plate-based assay and study of growth kinetics, coated fabric exhibited excellent anti-B. subtilis activity which demonstrated that biogenic SeBrs can be employed to coat cotton fabrics that can be used in operation theatres to reduce the episodes of Bacillus related Bacteraemia.

Inorganic Materials Synthesis Planning with Literature-Trained Neural Networks

Leveraging new data sources is a key step in accelerating the pace of materials design and discovery. To complement the strides in synthesis planning driven by historical, experimental, and computed data, we present an automated, unsupervised method for connecting scientific literature to inorganic synthesis insights. Starting from the natural language text, we apply word embeddings from language models, which are fed into a named entity recognition model, upon which a conditional variational autoencoder is trained to generate syntheses for any inorganic materials of interest. We show the potential of this technique by predicting precursors for two perovskite materials, using only training data published over a decade prior to their first reported syntheses. We demonstrate that the model learns representations of materials corresponding to synthesis-related properties and that the model's behavior complements the existing thermodynamic knowledge. Finally, we apply the model to perform synthesizability screening for proposed novel perovskite compounds.

Cadmium sulfide-induced toxicity in the cortex and cerebellum: In vitro and in vivo studies

Living organisms have an innate ability to regulate the synthesis of inorganic materials, such as bones and teeth in humans. Cadmium sulfide (CdS) can be utilized as a quantum dot that functions as a unique light-emitting semiconductor nanocrystal. The increased use in CdS has led to an increased inhalation and ingestion rate of CdS by humans which requires a broader appreciation for the acute and chronic toxicity of CdS. We investigated the toxic effects of CdS on cerebellar cell cultures and rat brain. We employed a ‘green synthesis’ biosynthesis process to obtain biocompatible material that can be used in living organisms, such as Viridibacillus arenosi K64. Nanocrystal formation was initiated by adding CdCl2 (1 mM) to the cell cultures. Our in vitro results established that increased concentrations of CdS (0.1 μg/mL) lead to decreased cell viability as assessed using 3-[4,5-dimethylthiazole-2-yl]-2,5-diphenyltetrazolium bromide (MTT), total antioxidant capacity (TAC), and total oxidant status (TOS). The in vivo studies showed that exposure to CdS (1 mg/kg) glial fibrillary acidic protein (GFAP) and 8-hydroxy-2' -deoxyguanosine (8-OHdG) were increased. Collectively, we describe a model system that addresses the process from the synthesis to the neurotoxicity assessment for CdS both in vitro and in vivo. These data will be beneficial in establishing a more comprehensive pathway for the understanding of quantum dot-induced neurotoxicity.

Navigating the design space of inorganic materials synthesis using statistical methods and machine learning.

Data-driven approaches have brought about a revolution in manufacturing; however, challenges persist in their applications to synthetic strategies. Their application to the deterministic navigation of reaction trajectories to stabilize crystalline solids with precise composition, atomic connectivity, microstructural dimensionality, and surface structure remains a frontier in inorganic materials research. The design of synthetic methodologies for the preparation of inorganic materials is often inefficient in terms of exploration of potentially vast design spaces spanning multiple process variables, reaction sequences, as well as structural parameters and reactivities of precursors and structure-directing agents. Reported synthetic methods are further limited in terms of the insight they provide into underlying chemical and physical principles. The recent surge in interest in accelerating the discovery of new materials can be considered as an opportunity to re-evaluate our approach to materials synthesis, and for considering new frameworks for exploration that are systematic and strategic in approach. Herein, we outline with the help of several illustrative examples, the challenges, opportunities, and limitations of data-driven synthesis design. The account collates discussion of design-of-experiments sampling methods, machine learning modeling, and active learning to develop experimental workflows that accelerate the experimental navigation of synthetic landscapes.

Green synthesis of Ag/TiO2 Nanocomposite Assisted by Gambier Leaf (Uncaria gambir Roxb) Extract

Studies of green synthesis of nanoparticles mediated by plants extract is extensively explored and studied in recent time due to eco-friendliness, cost-effectiveness, and use a minimum amount of toxic chemicals in the process of inorganic material synthesis. In this study, the immobilization of silver nanoparticles on the surface of titanium dioxide (TiO2) was carried out using Uncaria gambier Roxb. leaf extract as a silver ion (Ag+) reducing agent. The synthesized Ag/TiO2 nanocomposite was characterized by UV-Vis spectroscopy, X-ray diffraction (XRD), and Diffuse Reflectance Spectroscopy (DRS). The formation of silver nanoparticles was confirmed through UV-Vis spectroscopic analysis, which showed a silver surface plasmon resonance (SPR) band at 426 nm. The X-ray diffraction pattern shows that Ag can inhibit the transition of the anatase into rutile phase. The presence of Ag particles in TiO2 can increase the absorption ability from an initial wavelength of 407 nm to 438 nm. Based on the results of Rhodamin B degradation, it can be seen that Ag/TiO2 has a higher photocatalytic activity than bare TiO2 with 99% percent degradation at 120 minutes of irradiation time.

Text-mined dataset of inorganic materials synthesis recipes

Materials discovery has become significantly facilitated and accelerated by high-throughput ab-initio computations. This ability to rapidly design interesting novel compounds has displaced the materials innovation bottleneck to the development of synthesis routes for the desired material. As there is no a fundamental theory for materials synthesis, one might attempt a data-driven approach for predicting inorganic materials synthesis, but this is impeded by the lack of a comprehensive database containing synthesis processes. To overcome this limitation, we have generated a dataset of “codified recipes” for solid-state synthesis automatically extracted from scientific publications. The dataset consists of 19,488 synthesis entries retrieved from 53,538 solid-state synthesis paragraphs by using text mining and natural language processing approaches. Every entry contains information about target material, starting compounds, operations used and their conditions, as well as the balanced chemical equation of the synthesis reaction. The dataset is publicly available and can be used for data mining of various aspects of inorganic materials synthesis.

Bipolar Electrochemistry: A Powerful Tool for Electrifying Functional Material Synthesis.

Electrosynthesis is a powerful method for the synthesis of organic, inorganic, and polymeric materials based on electron-transfer-driven reactions at the substrate/electrode interface. The use of electricity for synthetic reactions without the need for hazardous chemical oxidants and reductants is recognized as a green and sustainable method. Other advantages include control of the reaction selectivity by tuning the electrode potentials. A different mode for driving electrochemical reactions has recently been proposed, in which bipolar electrodes (BPEs) are available as wireless electrodes that undergo anodic and cathodic reactions simultaneously. Bipolar electrochemistry is an old technology that has recently garnered renewed attention because of the interesting features of BPEs: (i) the wireless nature of a BPE is useful for sensors and material synthesis; (ii) the gradient potential distribution on BPEs is a powerful tool for the preparation of gradient surfaces and materials; and (iii) electrophoresis is available for effective electrolysis. In addition to these unique features, a BPE system only requires a small amount of supporting electrolyte in principle, whereas a large amount of electrolyte is necessary in conventional electrochemistry. Hence, bipolar electrochemistry is an inherently green and sustainable chemical process for the synthesis of materials. In this Account, recent progress in bipolar electrochemistry for the electrosynthesis of functional materials is summarized. The wireless nature of BPEs was utilized for symmetry breaking to produce anisotropic materials based on the site-selective modification of conductive objects by electrodeposition and electropolymerization. Potential gradients on a BPE interface have been successfully used as controllable templates to form molecular or polymeric gradient materials, which are potentially applicable for high throughput analytical equipment or as biomimetic materials. The electric field necessary to drive BPEs is also potentially useful to induce the directed migration of charged species. The synergetic effects of electrophoresis and electrolysis were also successfully demonstrated to obtain various functional materials. These features of bipolar electrochemistry and the various combinations of techniques have the potential to change the methodologies of material synthesis. Furthermore, the fundamental principle of bipolar electrochemistry infers that very small amounts of supporting electrolyte are necessary for an electrode system, which is expected to lead new methods of sustainable organic electrosynthesis.

Semi-supervised machine-learning classification of materials synthesis procedures

Digitizing large collections of scientific literature can enable new informatics approaches for scientific analysis and meta-analysis. However, most content in the scientific literature is locked-up in written natural language, which is difficult to parse into databases using explicitly hard-coded classification rules. In this work, we demonstrate a semi-supervised machine-learning method to classify inorganic materials synthesis procedures from written natural language. Without any human input, latent Dirichlet allocation can cluster keywords into topics corresponding to specific experimental materials synthesis steps, such as “grinding” and “heating”, “dissolving” and “centrifuging”, etc. Guided by a modest amount of annotation, a random forest classifier can then associate these steps with different categories of materials synthesis, such as solid-state or hydrothermal synthesis. Finally, we show that a Markov chain representation of the order of experimental steps accurately reconstructs a flowchart of possible synthesis procedures. Our machine-learning approach enables a scalable approach to unlock the large amount of inorganic materials synthesis information from the literature and to process it into a standardized, machine-readable database.

Synthesis and Characteristics of Inorganic Polymer Materials Geopolymerized from Ash of Brickyard

Inorganic polymer materials known as geopolymer-based materials are always interesting topics for researchers. Geopolymer is environmentally friendly material which has been potential applications for many different fields such as technical materials, building materials, insolation or refractories, and others. This study used ash of brickyard (AB) as a raw material for geopolymerization process to develop novel materials with high porosity. AB is industrial waste of the brick factories that need to be managed to reduce their negative impact to the environment. AB contains high alumino-silicate resources were mixed with sodium hydroxide solution for 10 minutes to obtain the geopolymer pastes. Sodium hydroxide solution was used as an alkaline activator to form geopolymer paste. The geopolymer paste was filled into 5-cm cube molds according to ASTM C109/C109M 99, and then cured at room temperature for 28 days. These products were then tested for compressive strength, volumetric weight, and water absorption. Results indicated that the material can be considered lightweight with a compressive strength at 28 days that are in the range of 8.1 to 15.4 MPa, volumetric weight around 600kg/m3 and water absorption is under 210.65 kg/m3. The properties of geopolymer products were also determined by analytical techniques that included mineral composition by X Ray Diffraction (XRD) and microstructure by scanning electron microscope (SEM).

Deep Learning Accelerated Gold Nanocluster Synthesis

The understanding of inorganic reactions, especially those far from the equilibrium state, is relatively limited due to the inherent complexity. Poor understanding of the underlying synthetic chemistry constrains the design of efficient synthesis routes toward the desired final products, especially those at atomic precision. Using the synthesis of atomically precise gold nanoclusters as a demonstration platform, a deep learning framework for guiding material synthesis is successfully developed to accelerate the workflow. With only 54 examples, the graph convolutional neural networks (GCNN) plus siamese neural networks (SNN) classification model is trained. The prediction capability is demonstrated with the successful prediction of literature‐reported protocols. In addition, understanding of the synthesis process can be acquired from a decision tree trained by plentiful generated data from a well‐trained classification model. This study not only provides a data‐driven method accelerating gold nanocluster synthesis, but also sheds light on understanding complex inorganic material synthesis with low data.

Dislocations that Decrease Size Mismatch within the Lattice Leading to Ultrawide Band Gap, Large Second‐Order Susceptibility, and High Nonlinear Optical Performance of AgGaS2

AbstractThe essence of rational design syntheses of functional inorganic materials lies in understanding and control of crystal structures that determine the physical properties. AgGaS2 has the highest figure of merit for IR nonlinear optical interactions to date, but suffers low laser‐induced damage threshold (LIDT). The partial Li substitution of Ag atoms is now shown to push up the bottom of the conduction band and flatten the top of the valence band, leading to an ultrawide band gap of 3.40 eV (record high for AgGaS2, indicating a transparency edging nearly 180 nm shorter than that of AgGaS2), which gives Li0.60Ag0.40GaS2 a LIDT 8.6 times stronger when AgGaS2 is compared. Li0.60Ag0.40GaS2 exhibits 1.1 times stronger nonlinear susceptibility, which is because the energy‐favorable Li substitution gradually decreases the sulfur dislocation in the lattice, which allows a better geometric superposition of nonlinear optical tensors.

Dislocations that Decrease Size Mismatch within the Lattice Leading to Ultrawide Band Gap, Large Second-Order Susceptibility, and High Nonlinear Optical Performance of AgGaS2.

The essence of rational design syntheses of functional inorganic materials lies in understanding and control of crystal structures that determine the physical properties. AgGaS2 has the highest figure of merit for IR nonlinear optical interactions to date, but suffers low laser-induced damage threshold (LIDT). The partial Li substitution of Ag atoms is now shown to push up the bottom of the conduction band and flatten the top of the valence band, leading to an ultrawide band gap of 3.40 eV (record high for AgGaS2 , indicating a transparency edging nearly 180 nm shorter than that of AgGaS2 ), which gives Li0.60 Ag0.40 GaS2 a LIDT 8.6 times stronger when AgGaS2 is compared. Li0.60 Ag0.40 GaS2 exhibits 1.1 times stronger nonlinear susceptibility, which is because the energy-favorable Li substitution gradually decreases the sulfur dislocation in the lattice, which allows a better geometric superposition of nonlinear optical tensors.

Chiral mesostructured SnO2 films with tunable optical activities

New strategies for tunable optical activities (OAs) are of fundamental importance in the advancement of science and technology. Here, we report hierarchically chiral mesostructured SnO2 films (CMSFs) deposited on FTO substrates via a symmetry breaking agent-inducing method. Three levels of chiral structures exist in the film, including tertiary plates helically arranged in fan-like form, secondary subplates helically stacked along [001] direction and primary nanosheets twisted along [100] direction. The thickness of plates was significantly increased with decreasing reactants concentration due to slower and preferential growth of plates along [001] direction. The increasing number of nanosheets results in enhancement and red shift of circular dichroism (CD) signals based on electron-transition absorption and reflection–based OA, which is in accordance with the circular Bragg resonance theory. Such novel chiral films with tunable OAs and morphologies may bring new ideas for design and synthesis of chiral inorganic materials with specific chirality and OA in the nanomaterial field.

Sonochemical synthesis of gum guar biopolymer stabilized copper oxide on exfoliated graphite: Application for enhanced electrochemical detection of H2O2 in milk and pharmaceutical samples

A novel and cost-effective synthesis of biopolymer-based organic and inorganic composite materials have received substantial attention in a broad range application including electroanalysis of small molecules. In this perspective, we report the synthesis of gum guar (guar) biopolymer stabilized cupric oxide decorated on exfoliated graphite (GR-guar/CuO) composite. Different physicochemical characterization methods were used to confirm the successful exfoliation of graphite and formation of the GR-guar/CuO composite. A simple sonochemical method has been used for the preparation of guar stabilized exfoliated graphite (GR-guar). The flower-like CuO on GR-guar and guar stabilized CuO (CuO-guar) composites were synthesized using a hydrothermal method. Cyclic voltammetric studies revealed that the GR-guar/CuO composite modified screen-printed carbon electrode (SPCE) had enhanced electro-reduction ability towards H2O2 than GR-guar and pristine graphite/CuO-guar modified SPCEs. Under optimized experimental conditions, the GR-guar/CuO composite modified electrode detects H2O2 in the response ranges from 0.02 to 1296.6 µM. The sensor shows a lower detection limit of 5.8 nM with high sensitivity. The as-prepared GR-guar/CuO composite sensor is highly reproducible and had excellent selectivity and practicality towards the detection of H2O2. Consequently, the fabricated sensor can be used for the accurate detection of H2O2 in real samples.