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A series of CeO2/CdS photocatalysts were prepared by simple solvothermal and auxiliary calcination using cerium nitrate as the precursor. Two different forms of CeO2 (nanosheets (NF-CeO2) and nanorods (NR-CeO2)) were successfully prepared and used to degrade rhodamine B (RhB) to study the photocatalytic activity of the composites. On this basis, the effects of composite proportion and preparation technology on the photocatalytic activity of the composites were studied. The morphology, structure, photoelectric properties and chemical composition of the composites were analyzed. Compared with single photocatalysts (NR-CeO2 and CdS), the NF-CeO2/CdS and NR-CeO2/CdS composite catalyst have stronger photocatalytic performance. In addition, capture experiments and ESR showed that both ∙ O 2 - and h+ impacted on the RhB degradation. After four repeated cycles, NR-CeO2/CdS (1:6) showed stable RhB degradation activity. In the aspect of catalyst interface design, this work not only provides an effective method for the preparation of catalysts with high photodegradation rate and good reuse, but also provides a feasible idea for further research on the degradation of emerging pollutants by photocatalysts. [ABSTRACT FROM AUTHOR]

[Objiectibe] Ammonia (NH3), a sustainable energy carrier and a vital industrial feedstock, plays a pivotal role in the progression of human civilization. Currently, ammonia is typically synthesized in factories using the Haber--Bosch method, which involves nitrogen (N2) and hydrogen (H2). This process consumes large amounts of energy and mostly gray hydrogen from fossil fuels, indicating that the Haber--Bosch method exerts enormous pressure on carbon emissions. To mitigate the growing environmental and energy challenges, investigating new methods for ammonia synthesis that are environmentally sustainable and have low energy consumption is crucial. Photocatalysis is an emerging catalytic technology that uses solar energy as an energy source and has the advantages of environmental friendliness and low energy consumption. Therefore, ammonia synthesis through photocatalysis has attracted the interest of many researchers. Graphite-phase carbon nitride (g-C3N4) with a narrow band gap (2.4--2.9 eV) has been widely used in photocatalytic reactions. However, the shortcomings of g-C3N4, such as low light absorption efficiency, poor effective charge-carrier separation, and weak N2 adsorption capacity, limit its further application in photocatalytic ammonia synthesis. [Methods] To overcome the disadvantages of g-C3N4, 2D/3D MoS2/HTCN heterojunction photocatalysts were prepared, and the feasibility of their photocatalytic reactions for ammonia synthesis was investigated. First, hollow tubular g-C3N4 (HTCN) was prepared to improve the light-absorbing ability of g-C3N4. Second, molybdenum disulfide (MoS2) nanosheets were loaded onto the HTCN surface to produce heterojunctions, enhancing the ability of the catalyst for carrier separation. In addition, the MoS2 nanosheets are superiorat absorbing N2, which aids in improving the N2 adsorption capacity of the MoS2/HTCN composites. Various tests were conducted to thoroughly investigate the properties of the synthesized catalysts. The structural and morphological features of samples were characterized using X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The optical and electrical properties of the samples were assessed using ultraviolet--visible spectroscopy, diffuse reflectance spectroscopy, photoluminescence, transient photocurrent, and electrochemical impedance spectroscopy. Energy band data were determined using the Tauc curves and Mott--Schottky analysis. Performance evaluation involved designing photocatalytic ammonia synthesis experiments under simulated sunlight conditionsby employing controlled variables to validate the origin of the synthesized NH3 from the N2 reduction by the catalyst. In addition, catalyst stability was examined through cycling experiments. [Results] The following results were obtained through the various above mentioned tests: 1 2D MoS2 nanosheets were successfully loaded onto the surface of 3D HTCN and exhibited a uniform distribution. 2 3D-structured HTCN has stronger light absorption than the bulk g-C3N4, and the loading of 2D MoS2 nanosheets further enhanced the light absorption of 2D/3D MoS2/HTCN. 3 2D MoS2 nanosheets formed a heterojunction with 3D HTCN and the built-in electric field at its interface promoted the separation of photoelectrons and holes. 4 In the photocatalytic nitrogen fixation experiment, the best performance was exhibited by 45% MoS2/HTCN, which is 9.5 times that of g-C3N4, 4.3 times that of HTCN, and 4.8 times that of MoS2. After five cycles, 45% MoS2/HTCN could maintain a photocatalytic nitrogen fixation efficiency of 81.63%. A Z-type 2D/3D MoS2/HTCN photocatalyst was synthesized via morphology modulation and heterojunction composites. [Conclusions] The hollow tubular structure of the catalyst enhanced the light absorption efficiency of g-C3N4. The heterojunction composites facilitated the separation of photogenerated carriers through the built-in electric field. In addition, the N2 adsorption capacity of the MoS2/HTCN composite materials improved because of the loading of 2D MoS2 nanosheets. Because of the aforementioned favorable conditions, the Z-type 2D/3D MoS2/HTCN photocatalyst exhibited a notable efficiency in reducing N2 to NH3, demonstrating an excellent photocatalytic ammonia synthesis capability. Characterized by comprehensiveness and novelty, this experimental study covers multiple aspects of catalyst preparation and testing, enhancing not only students' abilities in catalyst synthesis and characterization but also their scientific thinking and overall scientific literacy. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Dalian Polytechnic University is the property of Journal of Dalian Polytechnic University Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Despite their numerous excellent properties, metal sulfides are not particularly efficient at converting energy and purifying the environment, which limits their further applications. Fortunately, the energy conversion and environmental purification efficiencies of these materials have experienced notable advancements in recent years, accompanied by an improved understanding of their underlying mechanisms. Herein, progress in experimental researches in recent years on the engineering of single component metal sulfides by controlling morphology, construction of heterojunctions, and incorporating elements is reviewed. Methods to design and prepare metal sulfide‐based composites by building binary or ternary heterojunctions of metal sulfide/semiconductor/conductor are also discussed in detail. These materials are used in energy conversion and environmental purification systems, where they act as photocatalytic materials not only to split water, reduce carbon dioxide or nitrogen, but also to degrade pollutants (organic and inorganic) in water and gas. Finally, it is concluded by summarizing the research frontiers of metal sulfide nanomaterials in energy and environmental applications, as well as proposing potential challenges and future research directions. This work may contribute to a better understanding of metal sulfide nanocomposites and provide clues for the fabrication of more efficient metal sulfide‐based nanostructures for clean energy production and environmental remediation.

Morphology plays a crucial role in defining the optical, electronic, and mechanical properties of halide perovskite microcrystals. Therefore, developing strategies that offer precise control over crystal morphology during the growth process is highly desirable. This work presents a simple scheme to simultaneously grow distinct geometries of cesium lead bromide (CsPbBr3) microcrystals, including microrods (MR), microplates (MP), and microspheres (MS), in a single chemical vapor deposition (CVD) experiment. By strategically adjusting precursor evaporation temperatures, flux density, and the substrate temperature, we surpass previous techniques by achieving simultaneous yet selective growth of multiple CsPbBr3 geometries at distinct positions on the same substrate. This fine growth control is attributed to the synergistic variation in fluid flow dynamics, precursor substrate distance, and temperature across the substrate, offering regions suitable for the growth of different morphologies. Pertinently, perovskite MR are grown at the top, while MP and MS are observed at the center and bottom regions of the substrate, respectively. Structural analysis reveals high crystallinity and an orthorhombic phase of the as-grown perovskite microcrystals, while persistent photonic lasing manifests their nonlinear optical characteristics, underpinning their potential application for next-generation photonic and optoelectronic devices.

Abstract The development of semiconductor photocatalysts is of great significance for the realization of efficient photocatalytic hydrogen evolution (PHE). AgIn5S8, as an emerging ternary metal sulfide photocatalyst, possesses the advantages of suitable bandgap (1.7–2.0 eV), environment‐friendly elements, and strong photostability, which holds great potential to realize high‐efficiency PHE. Although AgIn5S8‐based photocatalysts have achieved promising research progresses, their PHE performances are still far below the level of commercial applications. In this review, the basic semiconductor properties of AgIn5S8 and PHE mechanism are first introduced in detail. Subsequently, the development process and PHE activities of AgIn5S8‐based photocatalysts are systematically summarized, mainly including morphology control, Schottky junction formation through cocatalyst loading, and construction of different types of heterojunctions. Finally, the current issues and the possible solutions of AgIn5S8‐based photocatalysts in future studies are presented.

Photocatalysis has emerged as a highly promising, green, and efficient technology for degrading pollutants in wastewater. Among the various photocatalysts, Bismuth tungstate (Bi2WO6) has gained significant attention in the research community due to its potential in environmental remediation and photocatalytic energy conversion. However, the limited light absorption ability and rapid recombination of photogenerated carriers hinder the further improvement of Bi2WO6's photocatalytic performance. This review aims to present recent advancements in the development of Bi2WO6-based photocatalysts. It delves into the photocatalytic mechanism of Bi2WO6 and summarizes the achieved photocatalytic characteristics by controlling its morphology, employing metal and non-metal doping, constructing semiconductor heterojunctions, and implementing defective engineering. Additionally, this review explores the practical applications of these modified Bi2WO6 photocatalysts in wastewater purification. Furthermore, this review addresses existing challenges and suggests prospects for the development of efficient Bi2WO6 photocatalysts. It is hoped that this comprehensive review will serve as a valuable reference and guide for researchers seeking to advance the field of Bi2WO6 photocatalysis. [ABSTRACT FROM AUTHOR]

Organic photovoltaic (OPV) sub‐modules shall be feasible for production using halogen‐free solvents in air,high power conversion efficiencies (PCEs), and long‐term stability, which are challenging requirements. To achieve this goal, air‐processed OPVs are fabricated by employing a synthesized set of π‐conjugated polymers, NAP‐T‐SiBTZ (P1) and NAP‐TT‐SiBTZ (P2), with thiophene and thienothiophene π‐spacers, respectively. P1 and P2 incorporated ternary OPVs show excellent PCEs and are used to produce small‐area, sub‐module air‐processed devices using o‐xylene as the solvent. Interestingly, P2‐added ternary devices has remarkable PCEs of 17.62% (PM6:P2:Y7) and 17.96% (PM6:P2:L8‐BO), which is the highest reported for air‐processed OPVs.. Notably, P2‐associated ternary blends exhibit a nano‐morphology, increased charge carrier mobilities, exciton dissociation, and decreased non‐geminate recombination, which are deemed responsible for the enhanced PCEs observed. In addition, P2 demonstrates high efficiency for a thick‐film device (>300 nm), with a PCE of >16.50%. Notably, a 55 cm2 sub‐module produced by bar coating using o‐xylene in open air has a PCE of 13.88%. Additionally, P2‐containing devices demonstrate impressive thermal and photo‐stabilities. This study shows the potential of an OPV that may be used to produce low‐cost solar cell sub‐module at low cost with exceptional commercial value. [ABSTRACT FROM AUTHOR]

The slot-die coating is recognized as the most compatible method for the roll-to-roll (R2R) processing of large-area flexible organic solar cells (OSCs). However, the photovoltaic performance of the large-area flexible all-polymer solar cells was significantly lagging behind that of polymer donors with small molecule non-fullerene acceptors devices. In this work, the 1 cm2 flexible device of an all-polymer system, PTQ10:PYF-T-o, fabricated by slot-die coating, achieves an excellent efficiency of 11.24% via controlling the coating temperatures. It is found that, compared with the donor, the crystallinity of PYF-T-o plays a crucial role in device performance. The all-polymer flexible devices show superior mechanical bending stability, maintaining an efficiency of over 95% of the initial value during a 1000-cycle bending test. [ABSTRACT FROM AUTHOR]

Migraine is now the sixth most common disease in the world and affects approximately 15% of the population. Non-steroidal anti-inflammatory drugs, including ketoprofen, diclofenac sodium, and ibuprofen, are often used during migraine attacks. Unfortunately, their efficiency can be reduced due to poor water solubility and low cellular uptake. This requires the design of appropriate porous carriers, which enable drugs to reach the target site, increase their dissolution and stability, and contribute to a time-dependent specific release mode. In this research, the potential of the MIL-88A metal-organic frameworks with divergent morphologies as diclofenac sodium delivery platforms was demonstrated. Materials were synthesized under different conditions (temperature: 70 and 120 °C; solvent: distilled water or N,N-Dimethylformamide) and characterized using X-ray diffraction, low-temperature nitrogen adsorption/desorption, thermogravimetric analysis, infrared spectroscopy, and scanning electron microscopy. They showed spherical, rod- or diamond-like morphologies influenced by preparation factors. Depending on physicochemical properties, the MIL-88A samples exhibited various sorption capacities toward diclofenac sodium (833–2021 mg/g). Drug adsorption onto the surface of MIL-88A materials primarily relied on the formation of hydrogen bonds, metal coordination, and electrostatic interactions. An in vitro drug release experiment performed at pH 6.8 revealed that diclofenac sodium diffused to phosphate buffer in a controlled manner. The MIL-88A carriers provide a high percentage release of drug in the range of 58–97% after 24 h. [ABSTRACT FROM AUTHOR]

The design and fabrication of nanomaterials with controllable morphology and size is of critical importance to achieve excellent catalytic performance in heterogeneous catalysis. In this work, cobalt oxide (Co3O4) nanostructures with different morphologies (nanoplates, microflowers, nanorods and nanocubes) were successfully constructed in order to establish the morphology–property–performance relationship of the catalysts. The morphology and structure of the nanostructured Co3O4 were characterized by various techniques, and the catalytic performance of the as-prepared nanostructures was studied by monitoring the reduction of p-nitrophenol to p-aminophenol in the presence of excess NaBH4. The catalytic performance was found to be strongly dependent on their morphologies. The experimental results show that the pseudo-first-order reaction rate constants for Co3O4 nanostructures with various shapes are, respectively, 1.49 min−1 (nanoplates), 1.40 min−1 (microflowers), 0.78 min−1 (nanorods) and 0.23 min−1 (nanocubes). The Co3O4 nanoplates exhibited the highest catalytic activity among the four nanostructures, due to their largest specific surface area, relatively high total pore volume, best redox properties and abundance of defect sites. The established correlation between morphology, property and catalytic performance in this work will offer valuable insight into the design and application of nanostructured Co3O4 as a potential non-noble metal catalyst for p-nitrophenol reduction. [ABSTRACT FROM AUTHOR]

[Display omitted] • Three types of g-C 3 N 4 (hollow nanotube, nanosheet and hollow nanosphere) were fabricated. • Morphology-induced piezoelectric property was revealed. • Nano-hollow tubular g-C 3 N 4 has advantages in absorbing stress to improve catalytic performance. • Various factors affecting the performance of piezocatalytic H 2 O 2 production were explored. • Active species were verified and new insight about the piezocatalytic mechanism was proposed. Piezocatalytic H 2 O 2 production has attracted significant attention as a green alternative to traditional anthraquinone methods with heavy environmental pollution and high energy consumption. However, since the efficiency of piezocatalyst in producing H 2 O 2 is poor, searching for a suitable method to improve the yield of H 2 O 2 is of great interest. Herein, a series of graphitic carbon nitride (g-C 3 N 4) with different morphologies (hollow nanotube, nanosheet and hollow nanosphere) are applied to enhance the piezocatalytic performance in yielding H 2 O 2. The hollow nanotube g-C 3 N 4 exhibited an outstanding H 2 O 2 generation rate of 262 umol·g−1·h−1 without any co-catalyst, which is 1.5 and 6.2 times higher than nanosheets and hollow nanospheres, respectively. Piezoelectric response force microscopy, piezoelectrochemical tests, and Finite Element Simulation results revealed that the excellent piezocatalytic property of hollow nanotube g-C 3 N 4 is mainly attributed to its larger piezoelectric coefficient, higher intrinsic carrier density, and stronger external stress absorption conversion. Furthermore, mechanism analysis indicated that piezocatalytic H 2 O 2 production follows a two-step single-electro pathway, and the discovery of 1O 2 furnishes a new insight into explore this mechanism. This study offers a new strategy for the eco-friendly manufacturing of H 2 O 2 and a valuable guide for future research on morphological modulation in piezocatalysis. [ABSTRACT FROM AUTHOR]

Electrospinning is a cost-effective and flexible technology for producing nanofibers with large specific surface areas, functionalized surfaces, and stable structures. In recent years, electrospun nanofibers have attracted more and more attention in electrochemical biosensors due to their excellent morphological and structural properties. This review outlines the principle of electrospinning technology. The strategies of producing nanofibers with different diameters, morphologies, and structures are discussed to understand the regulation rules of nanofiber morphology and structure. The application of electrospun nanofibers in electrochemical biosensors is reviewed in detail. In addition, we look towards the future prospects of electrospinning technology and the challenge of scale production.

The layer-by-layer (LBL) fabrication method allows for controlled microstructure morphology and vertical component distribution, and also offers a reproducible and efficient technique for fabricating large-scale organic solar cells (OSCs). In this study, the polymers D18 and PYIT-OD are employed to fabricate all-polymer solar cells (all-PSCs) using the LBL method. Morphological studies reveal that the use of additives optimizes the microstructure of the active layer, enhancing the cells’ crystallinity and charge transport capability. The optimized device with 2% CN additive significantly reduces bimolecular recombination and trap-assisted recombination. All-PSCs fabricated by the LBL method based on D18/PYIT-OD deliver a power conversion efficiency (PCE) of 15.07%. Our study demonstrates the great potential of additive engineering via the LBL fabrication method in regulating the microstructure of active layers, suppressing charge recombination, and enhancing the photovoltaic performance of devices.

Bimetallic sulfides offer high theoretical specific capacitance and good stability as electrode materials due to their diverse redox reactions, larger specific surface areas, and better conductivity. The morphology of the electrode material is an important influencing factor for the electrochemical properties. Herein, a series of ZnCoS electrode materials with different morphologies were prepared by varying the solvent in the solvothermal reaction, and the effects of different microstructures on the electrochemical properties of ZnCoS were investigated. The ratio of water and ethanol in the solvent was controlled to modulate the microstructure of the as-prepared ZnCoS materials. XRD and XPS revealed the physical and chemical structure of the ZnCoS materials. SEM and TEM observations showed that the microstructure of ZnCoS transformed from one-dimensional wires to two-dimensional sheets with increasing amounts of ethanol. The maximum specific capacitance of the as-prepared ZnCoS materials is 6.22 F cm−2 at a current density of 5 mA cm−2, which is superior to that of most previously reported bimetallic sulfides. The enhanced electrochemical performance could be ascribed to its sheet-assembled spherical structure, which not only shortens the path of ion diffusion but also increases the contact between surface active sites and the electrolyte. Moreover, the spherical structure provides numerous void spaces for buffering the volume expansion and penetration of the electrolyte, which would be favorable for electrochemical reactions. Furthermore, the ZnCoS electrodes were coupled with activated carbon (AC) electrodes to build asymmetric supercapacitors (ASCs). The ASC device exhibits a maximum energy density of 0.124 mWh cm−2 under a power density of 2.1 mW cm−2. Moreover, even under a high-power density of 21 mW cm−2, the energy density can still reach 0.055 mWh cm−2. [ABSTRACT FROM AUTHOR]

Copyright of Bulletin of the Chinese Ceramic Society is the property of Bulletin of the Chinese Ceramic Society Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Organic solar cells (OSCs) have been studied widely as renewable energy resources for a few decades owing to their technological advantages, including low cost, light weight, flexibility, and the potential of large area printing. To upgrade the active layers of OSCs into an optimized form, a simple and straightforward strategy is demonstrated by introducing two types of size‐controlled chevron (V)‐shaped blades to delicately control PM6:Y6‐based bulk heterojunction (BHJ) films under ambient conditions. A power conversion efficiency of 15.97% is achieved from the blade‐coating methods using a small‐sized V‐shaped blade (V1), compared with 14.31% using a conventional flat blade (F). Using blade coating based on V1 improves the phase separation and molecular crystallinity in the active layer, which lead to decreased trap‐assisted recombination and leakage current, finally increasing the short circuit current and fill factor. In addition, following these morphological changes in the optimal BHJ structure, the devices printed with V1 exhibit higher stability in the long‐term shelf‐life test (320 h storage in ambient conditions). Notably, strategy is a facile layer fabrication method that adopts V‐shaped blades to achieve high device performance and stability for the practical use of large‐area OSCs. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Carbon nanodots (CDs) with high photothermal performance are ideal candidates for tumor photothermal therapy (PTT). Herein, we investigated the photothermal performance of CDs synthesized from urea and citric acid via solvothermal method in dimethyl sulfoxide (DMSO) at different temperatures. Photothermal conversion efficiency (PCE) of up to 61.3% was obtained in the CDs synthesized at 150 °C (150‐CDs), which is much better than the CDs synthesized at 180 °C (180‐CDs). By analyzing the morphologies, chemical structures, and absorption spectra of these CDs, we found that the photothermal effect of the CDs was due to the lattice vibration of their carbonized cores, in which moderate carbonization with high content of surface carbonyl group (C=O) contributed for enhanced absorption band in deep red region with improved photothermal performance. Moreover, we also demonstrated that 150‐CDs with moderate carbonized cores exhibit much better tumor PTT performance in vivo than 180‐CDs with higher carbonized cores. [ABSTRACT FROM AUTHOR]

Comprehensive Summary: Carbon nanodots (CDs) with high photothermal performance are ideal candidates for tumor photothermal therapy (PTT). Herein, we investigated the photothermal performance of CDs synthesized from urea and citric acid via solvothermal method in dimethyl sulfoxide (DMSO) at different temperatures. Photothermal conversion efficiency (PCE) of up to 61.3% was obtained in the CDs synthesized at 150 °C (150‐CDs), which is much better than the CDs synthesized at 180 °C (180‐CDs). By analyzing the morphologies, chemical structures, and absorption spectra of these CDs, we found that the photothermal effect of the CDs was due to the lattice vibration of their carbonized cores, in which moderate carbonization with high content of surface carbonyl group (C=O) contributed for enhanced absorption band in deep red region with improved photothermal performance. Moreover, we also demonstrated that 150‐CDs with moderate carbonized cores exhibit much better tumor PTT performance in vivo than 180‐CDs with higher carbonized cores. [ABSTRACT FROM AUTHOR]

Two different shaped Ni‐based metal–organic framework (MOF) nanosheets are prepared from hexagonal nickel hydroxide monolayer nanosheets under the variable reaction conditions. The hexagonal shaped MOF with similar lateral size to Ni(OH)2 nanosheet is obtained on flat Si substrate but the thickness increased from 1 to 2 nm. Another rectangular MOF nanosheet is obtained when a similar reaction is carried out in a solution in which Ni(OH)2 is dispersed. The difference in the shape of the Ni‐MOF nanosheets is related to the degree of dissolution of the Ni(OH)2 nanosheets during the reaction. [ABSTRACT FROM AUTHOR]

In recent years, the power conversion efficiency of organic solar cells (OSCs) and perovskite (PVSCs) has increased to over 19% and 25%, respectively. Meanwhile, the long-term stability of OSCs and PVSCs was also significantly improved with a better understanding of the degradation mechanism and the improvement of materials, morphology, and interface stability. As both the efficiency and lifetime of solar cells are approaching the commercialization limit, fabrication methods for large-area OSCs and PVSCs that can be directly transferred from lab to fab become essential to promote the industrialization of OSCs and PVSCs. Compared with the coating methods, inkjet printing is a mature industrial technology with the advantages of random digital patterning, excellent precision and fast printing speed, which is considered to have great potential in solar cell fabrication. Many efforts have been devoted to developing inkjet-printed OSCs and PVSCs, and much progress has been achieved in the last few years. In this review, we first introduced the working principle of inkjet printing, the rheology requirements of inks, and the behaviors of the droplets. We then summarized the recent research progresses of the inkjet-printed OSCs and PVSCs to facilitate knowledge transfer between the two technologies. In the end, we gave a perspective on inkjet-printed OSCs and PVSCs. [ABSTRACT FROM AUTHOR]

Silver nanowires (AgNO3) with high aspect ratio are highly desirable for its downstream applications. Increasing the concentration of AgNO3 for synthesizing the AgNWs can improve the production efficiency, but ad ding the difficulty in morphology controlling of the products at the same time. Herein, elaborate morphology tuning of the AgNWs prepared in the high-concent ration AgNO3 solutions were realized. Specifically, the optimized conditions, including the types of ion additives (Fe+ and Cl-), molecular weight of polyethylene pyrrolidone (PVP) and the first-step AgNOs concentration as well as the addition rate of AgNOs, were obtained by systematically exploring their effects on the size of obtained AgNWs. The optimized conditions contribute to preparation of AgNWs with diameter and length being 71.0 nm and 62.3/im respectively, corresponding to the highest aspect ratio of 877.3. The SEM images and UV-vis spectrophotometer results show that the synergy of Fe3+ and Cl- determines the generation of AgNWs with high aspect ratio. Also, the optimizations of the PVP molecular weight and the first-step concentration of AgNOs as well as its addition rate can further improve the aspect ratio of the AgNWs. [ABSTRACT FROM AUTHOR]

Tn this work, morphology control of In2O3 gas sensing materials was realized through controlling the hydrothermal synthesis conditions, and Tn2O3 with zero to three dimensional morphologies (nanoparticles, nanorods, nanosheets, and microspheres) were prepared directionally. The morphology, structure, and chemical properties of In2O3 were characterized by various methods, and their gas sensing performances toward NO, were systematically investigated. The gas sensing test results showed that NO2 gas sensing performances were significantly improved through morphology control. Among them, Tn2O3 microspheres with the largest surface area and chemisorbed oxygen species exhibited the optimum gas sensing performances to NO2 and the sensor fabricated with In2O3 microspheres reached a high response of 695 to 5.0X10-6 NO2 under 100 °C and can detect NOv down to 0.2X10-6 showing high selectivity and reliable repeatability. Finally, the influential mechanism of In2O3 morphology control on NO, gas sensing performances was further discussed. [ABSTRACT FROM AUTHOR]

Microwave absorbing materials (MAMs) are playing an increasingly essential role in the development of wireless communications, high-power electronic devices, and advanced target detection technology. MAMs with a broad-bandwidth response are particularly important in the area of communication security, radiation prevention, electronic reliability, and military stealth. Although considerable progress has been made in the design and preparation of MAMs with a broad-bandwidth response, a number of challenges still remain, and the structure–function relationship of MAMs is still far from being completely understood. Herein, the advances in the design and research of MAMs with a broad-bandwidth response are outlined. The main strategies for expanding the effective absorption bandwidth of MAMs are comprehensively summarized considering three perspectives: the chemical combination strategy, morphological control strategy, and macrostructure control strategy. Several important results as well as design principles and absorption mechanisms are highlighted. A coherent explanation detailing the influence of the chemical composition and structure of various materials on the microwave absorption properties of MAMs is provided. The main challenges, new opportunities, and future perspectives in this promising field are also presented. [ABSTRACT FROM AUTHOR]

Dopamine (DA) plays a crucial role in the functioning of the human central nervous system, participating in both physiological and psychological processes. It is an important research topic in biomedical science. However, we need to constantly monitor the concentration of dopamine in the body, and the sensors required for this usually require good sensitivity in order to achieve fast and accurate measurements. In this research project, a CeO2 and CuCrO2 composite nanofiber was prepared for the electrochemical detection of dopamine. Coaxial electrospinning techniques were used to prepare CeO2–CuCrO2 composite nanofibers. The characterization techniques of X-ray diffractometer (XRD), Raman, and X-ray photoelectron spectroscopy (XPS) were used to analyze the composite's crystal structure, vibrational bonds, and elemental composition, while SEM and TEM were used to analyze the composite's surface structure, morphology, and microstructure. The prepared nanofiber outer layer was found to have an average thickness of 70.96 nm, average fiber diameter of 192.49 nm, and an average grain size of about ~12.5 nm. The BET analysis was applied to obtain the specific surface area (25.03 m2/gm). The proposed nanofiber-decorated disposable screen-printed carbon electrode acted as a better electrochemical sensor for the detection of dopamine. Moreover, the electrocatalyst had a better limit of detection, 36 nM with a linear range of 10 to 100 μM, and its sensitivity was 6.731 μA μM−1 cm−2. In addition, the proposed electrocatalyst was successfully applied to real-time potential applications, namely, to the analysis of human urine samples in order to obtain better recovery results. [ABSTRACT FROM AUTHOR]

The SmMn2O5 catalyst is considered as an excellent substitute for noble-metal and transition-metal oxide catalysts due to its unique crystal structure. In order to further improve its catalytic activity for acetone degradation, SmMn2O5 nanocatalysts with four morphologies were synthesized by the hydrothermal method by adjusting the type of manganese source reagent, the content of mineralizing agent, and hydrothermal temperature. Among them, the SMO-NF catalyst prepared with Mn-(NO3)2 as the manganese source, 10 mL of NaOH, and a hydrothermal temperature of 220 °C has a special flower morphology and can achieve 100% acetone conversion at 118 °C. Because of its thin and large "petal" morphology providing active sites and oxygen vacancies, the excellent catalytic performance of the SMO-NF catalyst is an important breakthrough in the field of acetone degradation. In addition, the highly stable crystalline phase, abundant surface reactive oxygen species, and excellent reducibility of the SMO-NF catalyst also lay the foundation for its high catalytic activity, water resistance, and stability. The SMO-NS catalyst with a spherical morphology can completely degrade acetone at 136 °C, and its activity is better than that of the SMO-CP catalyst prepared by the coprecipitation method and Pt/TiO2 catalysts. The relationship between the formation process of SmMn2O5 nanocatalysts with special morphology and its catalytic activity is discussed as well. The successful synthesis of the SMO-NF catalyst also opens up a way for the synthesis of the special morphology of acetone degradation nanocatalysts. [ABSTRACT FROM AUTHOR]

A series of POMs/EuF3 (POMs = α-PMo12, α-PW9) nanocrystals with uniform morphologies have been successfully synthesized under mild solution conditions by introducing different polyoxometalates as dopants and shape modifiers. Detailed experiments reveal that the morphologies and size of the EuF3 nanocrystals could be finely tuned by changing the fluorine source, type and amount of polyoxometalates. Moreover, the emissions of EuF3 nanoplates are disappeared partially during the photoluminescence tests, indicating polyoxometalates plays a key role in the regulation of the fluorescence characteristics of EuF3 nanoplates. Therefore, the strategy of doping polyoxometalates can provide a new idea to adjust the morphologies and fluorescence characteristics of rare earth fluoride. It is worth to expect this kind of nanomaterial could be finely applied as an active material in fluorescent chemical sensors, optoelectronic devices or bio-imaging. [ABSTRACT FROM AUTHOR]

To achieve excellent electromagnetic wave (EMW) absorption properties, the microstructure design of the absorber is critical. In this work, six kinds of N-Ni/C nanostructures with different morphologies were prepared by one-step hydrothermal method and high temperature carbonization by adjusting the types of nickel salts and reaction solvents. The EMW absorption performance of six different morphologies of N-Ni/C nanostructures was compared and analyzed. Among them, it is found that the nanoflower-like N-Ni/C composite has excellent dielectric loss and magnetic loss synergistic effect due to its polycrystalline structure, and can obtain excellent EMW absorption performance. The minimum reflection loss value at a thickness of 1.9 mm is −59.56 dB at 16.88 GHz, and the effective absorption bandwidth value reaches 6.0 GHz at a thickness of 2.2 mm. Our research shows that different morphologies and multiple lattice structures of nanostructures with the same composition have a significant influence on EMW absorption performance, which provides new research ideas for developing high-performance EMW absorbing materials. [ABSTRACT FROM AUTHOR]

Copyright of Polymer Materials Science & Engineering is the property of Sichuan University, Polymer Research Institute and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Oriented microstructures are widely found in various biological systems for multiple functions. Such anisotropic structures provide low tortuosity and sufficient surface area, desirable for the design of high-performance energy storage devices. Despite significant efforts to develop supercapacitors with aligned morphology, challenges remain due to the predefined pore sizes, limited mechanical flexibility, and low mass loading. Herein, a wood-inspired flexible all-solid-state hydrogel supercapacitor is demonstrated by morphologically tuning the aligned hydrogel matrix toward high electrode-materials loading and high areal capacitance. The highly aligned matrix exhibits broad morphological tunability (47–12 µm), mechanical flexibility (0°–180° bending), and uniform polypyrrole loading up to 7 mm thick matrix. After being assembled into a solid-state supercapacitor, the areal capacitance reaches 831 mF cm−2 for the 12 µm matrix, which is 259% times of the 47 µm matrix and 403% times of nonaligned matrix. The supercapacitor also exhibits a high energy density of 73.8 µWh cm−2, power density of 4960 µW cm−2, capacitance retention of 86.5% after 1000 cycles, and bending stability of 95% after 5000 cycles. The principle to structurally design the oriented matrices for high electrode material loading opens up the possibility for advanced energy storage applications.

Abstract Due to the growing demand for clean and renewable hydrogen fuel, there has been a surge of interest in electrocatalytic water‐splitting devices driven by renewable energy sources. However, the feasibility of self‐driven water splitting is limited by inefficient connections between functional modules, lack of highly active and stable electrocatalysts, and intermittent and unpredictable renewable energy supply. Herein, we construct a dual‐modulated three‐dimensional (3D) NiCo2O4@NiCo2S4 (denoted as NCONCS) heterostructure deposited on nickel foam as a multifunctional electrode for electrocatalytic water splitting driven by photovoltaic‐powered supercapacitors. Due to a stable 3D architecture configuration, abundant active sites, efficient charge transfer, and tuned interface properties, the NCONCS delivers a high specific capacity and rate performance for supercapacitors. A two‐electrode electrolyzer assembled with the NCONCS as both the anode and the cathode only requires a low cell voltage of 1.47 V to achieve a current density of 10 mA cm−2 in alkaline electrolyte, which outperforms the state‐of‐the‐art bifunctional electrocatalysts. Theoretical calculations suggest that the generated heterointerfaces in NCONCS improve the surface binding capability of reaction intermediates while regulating the local electronic structures, which thus accelerates the reaction kinetics of water electrolysis. As a proof of concept, an integrated configuration comprising a two‐electrode electrolyzer driven by two series‐connected supercapacitors charged by a solar cell delivers a high product yield with superior durability.

One-dimensional Si 3 N 4 wires and belts have been successfully synthesized via pyrolysis of polyvinylsilazane (PVSZ) with nano-SiO 2 powders as the additive. The morphology of white Si 3 N 4 was tailored from wire-like morphology to belt-like morphology by controlling pyrolysis temperature. The maxlength of Si 3 N 4 wires and belts is up to 550 μm. The diameter of Si 3 N 4 wires is 200–300 nm and the width and thickness of belts are 1–2.5 μm and 130–250 nm respectively. Nano SiO 2 powders induced the formation of SiO 2 phase in the substrate and promoted the growth of α-Si 3 N 4 belts. Vapor-solid is the growth mechanism for Si 3 N 4 microwires and micorbelts. Si 3 N 4 wires and belts have broad blue emission ranging from 410 nm to 550 nm. [ABSTRACT FROM AUTHOR]

One of the grand challenges of amphiphilic self-assembly is the design of ordered structures whose morphology or shape can be explicitly and dynamically controlled by adjusting the properties of the amphiphiles or their surroundings. Such a capacity would enable researchers to create synthetic systems with functionality that meets or exceeds biological cells, and provide a robust platform for a broad range of engineering applications such as artificial tissues, drug delivery, and separation membranes. Despite significant progress, important fundamental questions remain unanswered, due in part to the limited resolution and the restricted parameter spaces that are readily accessible in experiments. Computational studies thus provide an important complement to experiments, enabling in-depth insight into underlying mechanisms and an exploration of the parameter spaces for behavior that has not yet been achieved in experiments. In this review, we briefly introduce fundamental concepts and pertinent experiments related to dynamic shape modulation in selfassembled amphiphiles. Then, in the bulk of the review, we survey the most influential simulation studies that investigate and identify approaches to control the self-assembled shape of amphiphiles, with an emphasis on kinetic and mechanical effects. Finally, we conclude with a perspective on future research directions in this exciting field. [ABSTRACT FROM AUTHOR]

Around a quarter of annual worldwide silver consumption comes from recycling. It remains a primary target for researchers to increase the silver ion adsorption capacity of the chelate resin. Herein, a series of flower-like thiourea–formaldehyde microspheres (FTFM) possessing diameters of 15–20 μm were prepared via a one-step reaction under acidic conditions, and the effects of the monomer molar ratio and reaction time on the micro-flower morphology, specific surface area, and silver ion adsorption performance were explored. The nanoflower-like microstructure showed the maximum specific surface area 18.98 ± 0.949 m2/g, which was 55.8 times higher than that of the solid microsphere control. As a result, the maximum silver ion adsorption capacity was 7.95 ± 0.396 mmol/g, which was 10.9 times higher than that of the control. Kinetic studies showed that the equilibrium adsorption amount of FT1F4M was 12.61 ± 0.016 mmol/g, which was 11.6 times higher than that of the control. Additionally, the isotherm study of the adsorption process was performed, and the maximum adsorption capacity of FT1F4M was 18.17 ± 1.28 mmol/g, which was 13.8 times that of the control according to the Langmuir adsorption model. Its high absorption efficiency, convenient preparation strategy, and low cost recommend FTFM bright for further use in industrial applications. [ABSTRACT FROM AUTHOR]

Zein was dissolved in different ratios of ethanol/water solvents to prepare micro/nano nonwoven materials by electrospun technology. The material was treated by solvent fumigation to study the effect of fiber morphology of zein micro/nano nonwoven materials on the air filtration performance. When the mass ratio of ethanol to water in the solvent was 6:4, the cross-section of zein fibers was round and the fibers showed rod-like morphology. When the mass ratio of ethanol to water was greater than 6:4, the cross-section of zein fibers was elliptical and flat, and the fibers showed a self-rotating curved ribbon-like morphology. When the mass ratio of ethanol to water was 7:3, the ribbon-like fiber membrane had the smallest average pore size and the highest air filtration efficiency. The thickness of the ribbon-like fiber membrane increases by 76.19% and the porosity increases by 37.59%, while the filtration efficiency increases by 3.85%, the filtration resistance decreases by 72.63% and the quality factor increases by 334.72% compared with the rod-like fiber membrane under the same spinning time. The breaking strength of the fumigation-treated ribbon-like fiber membrane increased by about 5 times. The zein micro/nano nonwoven material can effectively remove formaldehyde, laying the foundation for the application of electrospun zein fiber in the field of multifunctional air filtration with high efficiency and low resistance. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Petroleum Research & Studies is the property of Republic of Iraq Ministry of Higher Education & Scientific Research (MOHESR) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Cobalt nanowires with different shapes and sizes were synthesized by reduction of carboxylate salts of CoII in 1, 2-butanediol using a solvothermal chemical process. The well-crystallized Co nanowires with hexagonal close-packed (hcp) phase are observed and the (002) crystalline direction is along the long axis of nanowires. The morphology control is strongly dependent on the reaction parameters. By varying the amount of capping agent in proper ranges, the effect of reaction parameters on controlling the size and shape of Co nanowires is demonstrated. With the amount of capping agent increasing, the aspect ratio of Co nanowires increases remarkably. However, the magnetic measurement of cobalt nanowires shows that the coercivity of the Co nanocrystals does not increase with the increase in aspect ratio monotonously, which suggests that the tip shape and microstructure also play an important role in the magnetization reversal process of the Co nanocrystals, and the aspect ratio plays a much less role as the ratio value exceeds 11. To further understand the effect of size on the magnetic properties in the Co nanowires, micromagnetic simulations were performed, which confirms that the magnetic properties are barely affected by the aspect ratio larger than 10. The highest coercivity of 624 kA·m−1 is obtained for ellipsoid nanowires with a mean length of 200 nm, which also displays a strong magnetic anisotropy. As a result, the highest energy product of the wires reaches 248 kJ·m−3. [ABSTRACT FROM AUTHOR]

This article demonstrates how purging the reaction medium with argon, oxygen, or CO during the liquid-phase synthesis affects the transformation dynamics of the Pt(IV) into Pt(0)x as well as the morphology of the Pt/C obtained. The reaction media studied are typical for the polyol and formic acid synthesis methods. The real-time monitoring of the Pt(0)x formation in these systems has been studied by the potentiometric and colorimetric measurements. The nature of a gas has been shown to affect the size of the small Pt particles formed as well as their different spatial distribution over the carbon support surface. Therefore, a gas is supposed to provide an additional control over both the formation of colloidal Pt and the microstructure of the Pt/C obtained. Moreover, this study illustrates a novel approach to using a platinum indicator electrode for the estimation of the reaction system's redox state during the synthesis of Pt nanoparticles. [ABSTRACT FROM AUTHOR]

A series of GdPO 4 :5%Eu3+ micro/nanomaterials with different morphologies and crystal structures were successfully prepared by the one-step solvothermal method using only the gadolinium source, the phosphoric acid source and ethanol as solvents, without any surfactants or templates, without further calcination and by adjusting only the ratio of phosphoric acid and gadolinium sources. They all have good dispersion and homogeneity. The morphology of the products was mainly regulated by the ratio of H 3 PO 4 to Gd(NO 3) 3 · 6H 2 O, with ratios of 2:1, 8:1, 16:1, 24:1, 32:1, 40:1 and 48:1 mL/g resulting in the formation of square, pillow, star, carambola, hollow cylinder, drum and jujube shaped GdPO 4 :5%Eu3+ micro/nanomaterials, respectively. Ratios of 2:1–24:1 and 32:1–48:1 allow for the direct solvothermal synthesis of monoclinic and hexagonal phase gadolinium phosphate, simultaneously. In addition to their crystal structure and morphology, chemical bonding, thermal stability and specific surface area, their luminescence properties and magnetic resonance imaging (MRI) tracing properties have also been studied in comparison. Interestingly, the GdPO 4 :5%Eu3+ micro/nanoparticles in the carambola shape had a higher photoluminescence intensity and relaxation rate of 0.7709 mM−1 s−1 (r 1) among all the morphologies. The possible mechanisms by which various morphologies of GdPO 4 :5%Eu3+ were prepared in different ratios were analyzed, and the reasons for their effects on the fluorescence and MRI tracer properties were further investigated. This study is of reference significance for the simple-regulated synthesis of rare earth inorganic gadolinium-containing micro/nanomaterials and provides a reliable guarantee for the expansion of their multifunctional applications in UV–Vis luminescence and MRI tracing for implants. [ABSTRACT FROM AUTHOR]

[Display omitted] Owing to considerable energy constraints and global warming phenomenon, to find alternative sources of renewable and affordable energy has become a highly prerequisite in this current era. Use of sustainable technologies in this regard for renewable fuel retention applications has become more beneficial in encouraging the broad usage of clean energy. Conjugated microporous polymers (CMPs) are a distinct family of composites, that merge extensive the π-conjugation with microporous structure. The CMPs have been recognized as an essential subclass of porous composites, ever since their development in 2007. The CMPs have been developed with a number of distinct configurations and characteristics, which allows for the versatility of conjugated framework cellular implementations and mesoporous structure. The exploration of CMPs in sustainable fuel devices is crucial for the development of CMP-based composites and their use in sustainability and environmental design. Numerous network developing processes and synthesized building components provide a huge heterogeneity of CMPs with various characteristics and design patterns. As a consequence, CMPs have been employed here for cathode/anode materials for lithium ion batteries (LIBs), sodium/potassium LIBs, supercapacitors, fuel cell electrode for solar cell, hydrogen storage materials, photocatalytic hydrogen and oxygen production reaction (HER, OER), photocatalytic CO 2 reduction and so on. Due to the large surface areas of these composites, the distinctive charge storage mechanisms found in CMPs are explored, and a synopsis of how CMPs might facilitate ultrafast in desirable variety is presented. In addition, an evaluation between CMPs and linear polymers is presented, which provides further assistance for the synthesis of active materials. The most significant shortcomings experienced by CMPs in the domains of energy production have been evaluated, and potential strategies, synthetic process with reactions, physiochemical properties along with morphology have been demonstrated. Thus, this review is intended to be an entertaining and motivating study in the scientific community of the energy storage experts. [ABSTRACT FROM AUTHOR]

As the lightest family member of the transition metal disulfides (TMDs), TiS 2 has attracted more and more attention due to its large specific surface area, adjustable band gap, good visible light absorption, and good charge transport properties. In this review, the recent state-of-the-art advances in the syntheses and applications of TiS 2 in energy storage, electronic devices, and catalysis have been summarized. Firstly, according to the physical presentation of the TiS 2 synthesis reaction, it can be divided into a solid phase synthesis, a liquid phase synthesis and a gas phase synthesis. Secondly, we summarize the applications of TiS 2 in energy storage, electronic devices and catalytic: (1) The applications of TiS 2 nanostructure in energy storage direction from the aspects of Li-ion battery (LIB), Li–S battery (LSB), Na-ion battery (NIB), K-ion battery (KIB), Mg-ion battery (MIB), solar cells and hydrogen storage; (2) The applications of TiS 2 nanostructures in various electronic devices from thermoelectric devices, high power lasers and flexible devices; (3) Applications based on energy catalysis and environmental catalysis. Based on the various synthetic technologies and wide applications of TiS 2 , we firmly believe that the challenges of TiS 2 will be solved and become a hot star material in the future. Finally, we discuss the future scope and the current challenges arising from this fascinating material. [ABSTRACT FROM AUTHOR]

[Display omitted] The ability to tune size and morphology of self-assemblies is particularly relevant in the development of delivery systems. By tailoring such structural parameters, one can provide larger cargo spaces or produce nanocarriers that can be loaded by hydrophilic and hydrophobic molecules starting ideally from the same polymer building unit. We herein demonstrate that the morphology of block copolymer-based pH-triggered nanoplatforms produced from poly (2 - methyl - 2 - oxazoline) m - b -poly[2-(diisopropylamino)-ethyl methacrylate] n (PMeOx m - b -PDPA n) is remarkably influenced by the overall molecular weight of the block copolymer, and by the selected method used to produce the self-assemblies. Polymeric vesicles were produced by nanoprecipitation using a block copolymer of relatively low molecular weight (M n ∼ 10 kg.mol−1). Very exciting though, despite the high hydrophobic weight ratio (w PDPA > 0.70), this method conducted to the formation of core–shell nanoparticles when block copolymers of higher molecular weight were used, thus suggesting that the fast (few seconds) self-assembly procedure is controlled by kinetics rather than thermodynamics. We further demonstrated the formation of vesicular structures using longer chains via the solvent-switch approach when the "switching" to the bad solvent is performed in a time scale of a few hours (approximately 3 hs). We accordingly demonstrate that using fairly simple methods one can easily tailor the morphology of such block copolymer self-assemblies, thereby producing a variety of structurally different pH-triggered nanoplatforms via a kinetic or thermodynamically-controlled process. This is certainly attractive towards the development of nanotechnology-based cargo delivery systems. [ABSTRACT FROM AUTHOR]

Using copper chloride as the Cu source, glucose as the reducing agent, hexadecylamine and octadecylamine as capping agent, a series of Cu nanowires was prepared via hydrothermal reduction route. The configuration relationships among reaction temperature, reaction time, reductant ratio and capping agent molar ratio on Cu nanowires morphology (length-diameter ratio) were investigated. Result showed that the optimum conditions: reductant ratio 0.5, capping agent molar ratio 0.4/0.8,reaction temperature 110 ℃,and reaction time 6 h. The product cleaning method for settlement-layered-hydrothermal washing. The mean aspect ratio of the Cu nanowires prepared under the optimal process exceeds 95, with the mean diameter of 26 nm and the nanowire proportion of more than 90%. [ABSTRACT FROM AUTHOR]

Expectations for the sensing of very small amounts of gases and odors are increasing in many fields such as medicine, healthcare, and mobility. In recent years, nanomaterials with various forms such as needle-like, beltlike, sheet-like, and dendrite-like have been developed. These nanomaterials have been used to detect very small amounts of gas with a semiconductor gas sensor. In addition, detection of various gases and odor molecules has been realized using these gas sensors. In particular, in the field of ceramics, which requires high-temperature firing at several hundred degrees Celsius, the realization of “cold crystallization”, which has been a longstanding issue, has had a great impact. Nanomaterials with high surface area, unique shape, metastable crystal facets, etc. have been developed with cold crystallization of ceramics. These nanomaterials have improved the low-concentration gas detection characteristics of gas sensors and odor sensors. In this review, I would like to introduce the fabrication of new SnO2 nanomaterials and the development of gas and odor sensors using the SnO2 nanomaterials. [ABSTRACT FROM AUTHOR]

Abstract Two different shaped Ni‐based metal–organic framework (MOF) nanosheets are prepared from hexagonal nickel hydroxide monolayer nanosheets under the variable reaction conditions. The hexagonal shaped MOF with similar lateral size to Ni(OH)2 nanosheet is obtained on flat Si substrate but the thickness increased from 1 to 2 nm. Another rectangular MOF nanosheet is obtained when a similar reaction is carried out in a solution in which Ni(OH)2 is dispersed. The difference in the shape of the Ni‐MOF nanosheets is related to the degree of dissolution of the Ni(OH)2 nanosheets during the reaction.