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Semiconductor-metal heterostructure, especially represented by various inorganic semiconductors-platinum (Pt) hybrids, is widely applied in converting solar power to chemical energy. Given the scarcity of Pt and the availability of coupling, the development of a non-Pt regimen and facile assembly strategy is critical. In this study, CdxZn1-xS/Ti3C2 ultrathin MXene composites were availably prepared with a facile electrostatic assembly strategy. The unique 0D/2D assembly demonstrated remarkably enhanced performance toward photocatalytic hydrogen production compared with bare CdxZn1-xS. Spectroscopic characterization analysis and band theory discussion substantiated the effects of electronic interaction and the Schottky barrier arising from intimate contact of CdxZn1-xS and Ti3C2 MXene on the swift separation of photoinduced electron-hole pairs. Successful application of electrostatic self-assembled CdxZn1-xS with ultrathin MXene opens a new area of utilizing electrical difference and band theory to prepare rational semiconductor/MXene Schottky structure towards various photocatalytic reactions.

N-containing Ce2Si2.5Al0.5O3.5N3.5 (CeSiAlON) melilite was synthesized at 1550 and 1600 °C for 5 h from CeO2, Si, Al, and Al2O3 in nitrogen by using Y2O3 and transition-metal nitrates (Co(NO3)2∙6H2O and Ni(NO3)2∙6H2O) as additives. The effects of Y2O3 and transition-metal nitrates on the phase, microstructures and photoluminescence properties of CeSiAlON melilite were studied. The incorporation of Y2O3 can promote the reaction of raw materials to a low degree, and results in a unit cell shrinkage of CeSiAlON due to the smaller radius of Y atom than that of Ce atom. The transition-metal nitrates can accelerate the reaction clearly and facilitate the formation of CeSiAlON fibers. The photoluminescence (PL) properties of CeSiAlON melilite presents a board violet emission band because of the 5d-4f transitions of Ce3+, and the additives can enhance the PL emission intensities of specimen significantly.

Developing efficient, stable and economical electrocatalyst for oxygen evolution reaction (OER) is a significant pathway to produce clean energy from water splitting. Herein, the promising and highly efficient porous CoCrFeNiMo high entropy alloys (HEAs) were prepared by microwave sintering using Mg space holder. Owing to unique properties of high entropy alloys and abundant active surface area, the porous CoCrFeNiMo-20 Mg exhibits excellent catalytic performance and prominent electrochemical stability with a low overpotential of 220 mV to reach current density of 10 mA cm−2, a small Tafel slope of 59.0 mV dec-1 and long-term durability for 24 h in 1.0 M KOH. The results of microstructure and element states indicate that crystal defects, porous structure and villous hydroxides are the reasons for high OER performance of the CoCrFeNiMo. This work not only provides a new way to prepare electrocatalysts, but also proves the important application of high entropy alloys in functional materials.

In this work, different carbon sources, such as nano-sized carbon black (CB), carbon nanotubes (CNT), carbon fibers (CF) and graphene (GR), were reacted with titanium micro-powders, to synthesise titanium carbide (TiC) in the mixed molten salts of LiCl–KCl–KF at 1100 °C for 6 h. There experiments were performed to investigate the accuracy of “carbon-template-growth” mechanism for the formation of TiC, that was proposed previously using micro-sized titanium and submicro-sized CB powders. The products synthesised from the different carbon sources were observed and characterised by scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy. The results showed that the visual morphologies of the TiC products mainly retained the shapes of the as-received carbon sources, that is, they presented an equiaxed-shape with a grain size of 10–20 nm from CB, a shell layer along the outer surface of the CNTs and CF, and a flake-shape with the GR. These morphologies reveal that the formation of TiC is indeed controlled by the “carbon-template-growth” mechanism.

SiO2-based anodes for lithium ion batteries (LIBs) suffer from low conductivity and volume change in charge/discharge processes. It is reported that reasonable amorphous and nanometric characteristics can effectively improve the activity of SiO2 for Li+ storage. So, highly active SiO2@C nanofibers were prepared by electrospinning. Using X-ray diffraction (XRD), its amorphous characteristics were revealed. The results from scanning electron microscopy (SEM) and transmission electron microscopy (TEM) showed that it was a nanofiber structure. As an anode for LIBs, the SiO2@C nanofibrous electrode showed the discharge capacities of 675 and 188 mAh g−1 at 1 A g−1 (1000the cycle) and 10 A g−1 (5000th cycle), respectively. Even at 50 A g−1, it still maintained 88 mA h g−1 at 60,000 cycles, showing excellent stability and high rate.

β-Sialon powder containing nanofibers was synthesized at 1300–1450 °C for 5 h in nitrogen by using transition metals (Fe, Co and Ni) as catalysts. Such synthesis conditions obviously reduced the nitriding temperature (~100 °C) of β-Sialon and increased the degree of nitridation. Observations from the weight gain rates of specimens relative to the content of catalysts suggest that the nitridation process was accelerated sharply via the addition of 0–2.5 wt% metallic catalysts. In addition, the amount of nanofibers of β-Sialon found in the specimens increased with the amount of transition metals, which was governed by the VLS formation mechanism with the help of transition metals. It could be concluded that transition metals not only greatly accelerated the nitridation of Si but also facilitated the formation of β-Sialon nanofibers in the specimens, as the formed metal-containing liquid greatly enhanced the amount of vapor generation.

Synthesis of affordable electrocatalysts with high efficiency at low cost is crucial for large-scale water splitting. Molybdenum carbide (Mo2C) has been suggested to be a promising alternative to noble metal based electrocatalysts for water splitting. In this paper, we fabricated a nanotextured coating of wrinkled Ni-doped Mo2C on carbon fiber paper (CFP) from Ni, Mo and carbon black (CB) via a molten salt method. Such a novel electrocatalyst, denoted as Ni-Mo2CCB/CFP, shows an overpotential of 121.4, 209.3 and 426.4 mV to achieve a current density of 10, 20 and 50 mA cm−2 respectively in acidic medium. The hydrogen evolution reaction (HER) performance of other as-prepared CFP based electrodes (bare CFP, Mo2C/CFP, Mo2CCB/CFP, Ni-Mo2C/CFP and NiCx/CFP) also tested. We found that the addition of carbon black and the doping of Ni could significantly improve the electrocatalytic performance of Mo2C/CFP in terms of overpotential, Tafel slope and exchange current density. This work demonstrates a facile and scalable route using molten salt method for the synthesis of high-performance electrocatalysts from non-precious compounds on carbon materials.

Recently, g-C3N4 has exhibited excellent catalytic performances in photocatalytic water splitting for H2 and O2 generation, degradation of pollutants and CO2 reduction. However, the bulk g-C3N4 demonstrates some disadvantages such as low specific surface area, high defect density, fast recombination possibility of photogenerated electron-hole pairs, and non-recyclable characteristics, leading to low photocatalytic performance and efficiency. The three-dimensional (3D) network-like g-C3N4 composite materials constructed by nanotechnology can effectively improve the adsorption capacity, light response, structure stability and recyclability of photocatalysts, which results in a significant increase in the photocatalytic performance and utilization. It is a novel way to achieve high-efficient separation of photogenerated electron-hole pairs and improve photocatalytic activity. In this review, the recent research progresses especially the synthesis strategy of 3D g-C3N4 composite photocatalysts and their applications for photocatalytic water splitting, degradation of organic pollutants and CO2 reduction are firstly and systematically introduced and discussed. The review and prospect of 3D g-C3N4 composite materials can provide some new ideas and directions for the research and development of 3D g-C3N4 composite photocatalysts with high activity, strong adsorption, facile recyclability, and no secondary pollution.

In order to verify the “Al2O3-template-formation” mechanism of magnesium aluminate (MA) spinel proposed previously using Al2O3 and MgO micro-powders as raw materials, in this work, MA spinel was synthesized by nanograined, plate-like, and fibrous Al2O3 in LiCl molten salt at 1150 °C for 3 h, respectively. The products were characterized by XRD, SEM, TEM, and EDS techniques, and the grain size of the products and raw materials were analyzed. The results showed clearly that the MA spinel was initially nucleated and subsequently developed to octahedral crystal. When the reaction further took place, when using nanograined Al2O3, the newly formed MA spinel seeds initially moved and attached to the surface of the large octahedral MA spinel crystal, and they were subsequently engulfed by the large MA spinel crystal, which further grew via layer-by-layer to become micro-sized crystal. Using plate-like or fibrous Al2O3 raw material, MgO diffused continuously into the interior of Al2O3 to form MA spinel with a gradient growth from surface to depth. These revealed that whatever shape of Al2O3 was used, the synthesis of MA spinel was governed by “Al2O3-template formation mechanism”, i.e., by the reaction of MgO diffusion into the Al2O3 templet in the molten salt.

Due to various advantages, such as rich resources, sodium (Na) is considered an alternative to replace lithium (Li) for carbon nanomaterials. Na has a larger radius, which largely limits the application. With the analysis and discussion, it found that porous carbon with functional groups benefited for energy storage, so functional porous carbon was obtained by spray drying with subsequent annealing and nitric acid etching. Moreover, the surface was modified by functional groups, which can improve wettability and enhance cycling stability. So, as the anodes for sodium-ion batteries (SIBs), the porous C electrode can remain a discharge capacity of 150 mA h g−1 at 1 A g−1 after 1000 cycles. This study opens a pathway to the design of electrodes and hopes that it can apply in other relevant fields.

Novel g-C3N4/h′ZnTiO3-a′TiO2 (CN/h′ZT-a′T) ternary composites were successfully prepared by combining in-situ precursor-synthesized h′ZnTiO3-a′TiO2 (h′ZT-a′T) nanoparticle with nanoporous g-C3N4 (CN) powders. X-ray diffraction (XRD), Transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) results revealed that the grains of hexagonal-phase ZnTiO3 (h′ZT) were in-situ generated together with anatase-phase TiO2 (a′T), forming a symbiotic structure of tightly bonded interface. Compared with CN and h′ZT-a′T, the absorption edge of CN/h′ZT-a′T exhibited a red-shift and the absorption intensity was obviously enhanced. With increasing CN content, the degradation efficiency of CN/h′ZT-a′T for methylene blue (MB) initially increased and then decreased, reaching the highest value of 99.8% with the CN content of 50 wt% (50CN/h′ZT-a′T). The 50CN/h′ZT-a′T composites exhibited the highest apparent reaction rate constant of 2.92 h−1, which was 37.4 and 3.0 times higher than that of h′ZT-a′T and CN, respectively. Photocurrent response of 50CN/h′ZT-a′T was indicative of the highest photocurrent value and the elongated lifetime of photogenerated charges. The greatly enhanced photocatalytic activity was attributed to the high mobility of photogenerated electrons. H′ZnTiO3 with high electron mobility in the direct Z-scheme heterojunction played a role of electronic transfer station and reduced the recombination probability of photogenerated carriers.

Single-crystal MoO3 micrometer to millimeter even centimeter belts were prepared via a novel route of oxidizing a discarded molybdenum disilicide heating element at 1000 °C for 3 h. The morphology and structure features, and growth mechanism of the products were evidently investigated by X-ray diffraction, Fourier transform infrared spectroscopy, X-ray photoelectron spectroscopy, scanning electron microscopy, and transmission electron microscopy. The results indicated that the powdery and fibrous products were typical α-MoO3 belt-like structures which size could develop from micrometer to several millimeter even centimeter in length and up to 0.5 mm in width. It should be formed preferentially along the [001] direction via layer by layer growth to form 1-D single MoO3 belts by vapor-solid mechanism. Thermal and luminescence properties of the products were revealed by thermogravimetric analysis and differential thermal analysis and photoluminescence spectra that the resultant α-MoO3 belts had good thermal stability and characteristics of luminescence with a central peak at 481 nm. The MoO3 belts are of good potential being applied to luminescent and high temperature devices.

Ca-α-Sialon powders was initially synthesized by carbothermal reduction-nitridation (CRN) of SiO2, AlN, CaF2 and carbon black at 1700 °C, subsequently was used as the raw material to prepare Ca-α-Sialon ceramic by hot-pressed (HP) sintering at 1900 °C. The main intermediate nitridated products were Si2N2O and O-Sialon formed at 1400 °C–1600 °C. The resultant Ca-α-Sialon just had hexagonally short prismatic structure at 1700 °C. In order to obtain its elongated crystals, α-Sialon seeding was introduced during CRN process. The results revealed that the seeding facilitated crystal refinement of Ca-α-Sialon and the increase in its aspect ratios from 2 to 5.45. The resultant HP-sintered Ca-α-Sialon ceramic with seeding at 1900 °C had compact structure with fine and elongated grains, forming a highly interlocked microstructure. They had a Vickers indentation hardness of ∼21 GPa independent of the microstructure. The flexural strength and fracture toughness of the Ca-α-Sialon ceramics drastically increased with increasing the amounts of seeds, which was in accordance with that in grains aspect ratio of α-Sialon crystals synthesized by CRN as function of amounts of seeds. The improved flexural strength and fracture toughness should be ascribed to the development of elongated α-Sialon grains, which could enhance crack deflection and grain pullout.

The development of cheap, efficient and high activity non-noble-metal oxygen evolution reaction (OER) electrocatalysts is of great interest in promoting the application of water splitting. Herein, the flower-like phosphates were grown in situ on a porous microwave sintered CoCrFeNiMo high entropy alloy (HEA) by the hydrothermal–phosphorization method. The metal phosphates can promote the formation of hydroxides with high catalytic activity on the surface of the catalyst. The obtained porous HEA phosphates exhibit a low overpotential of 220 mV at 10 mA cm−2, a small Tafel slope of 30.3 mV dec−1 and superior stability in 1.0 M KOH. Especially, after continuous cyclic voltammetry (CV) 5000 cycles, the catalyst only requires the overpotential of 210 mV at 10 mA cm−2. The enhanced OER performance of this porous HEA is be attributed to 3D internal connected nanoporous structure, high conductivity, abundant metal (oxy)hydroxide nanosheets and the presence of phosphonates, that provides a sufficiently large surface exposure and allows the acceleration of the electron transfer rate between various species.

Nanohybrids of graphene-decorated carbon-coated LiFePO4 nanospheres are prepared using a ball milling-assisted rheological phase method combined with a solid-state reaction. The hybrids are characterized by XRD, SEM, TEM, HRTEM, XPS, Raman and TGA, and their electrochemical properties are studied by CV, EIS and galvanostatic charge-discharge. The experimental results exhibit that multilayer graphene films are decorating carbon-coated LiFePO4 nanospheres without stacking, which results in an abundance of mesopores constituting a unique 3D “sheets-in-pellets” and “pellets-on-sheets” conducting network structure. This structure highlights the improvements of the rate and cyclic performance as a cathode material for lithium-ion batteries, because the highly conductive and plentiful mesopores promote electronic and ionic transport. As a result, the hybrids with approximately 3 wt% graphene exhibit an outstanding rate capability with an initial discharge capacity of 163.8 and 147.1 mA h g−1 at 0.1 C and 1 C, and the capacity is retained at 81.2 mA h g−1 even at 20 C. Moreover, the composites also reveal an excellent cycling stability with only an 8% capacity decay at 10 C after 500 cycles.

Graphitic carbon nitride (g-C 3 N 4 ) prepared by traditional methods has various disadvantages, e.g., small specific surface area, low band gap, high photo-generated carriers recombination and low exfoliation efficiency, which limits its practical application. In this study, folded nano-porous graphene-like g-C 3 N 4 (abbreviated as FNPGLCN) was prepared by a simple but quite effective method of calcining urea in water. The effects of calcination temperature on crystal structure, energy band and microstructure of g-C 3 N 4 were investigated. The photocatalytic activity for methylene blue (MB) degradation under visible-light was evaluated. The results revealed that the FNPGLCN had higher specific surface area (197 m 2 /g) and larger band gap (2.87 eV) than bulk g-C 3 N 4 . With calcination temperature rising from 450 to 500 °C, the pore size and specific surface area of FNPGLCN increased. However, the pore structure almost disappeared and the thickness of g-C 3 N 4 became thinner at 550 °C. Compared with bulk g-C 3 N 4 , the photocatalytic degradation rate of FNPGLCN for MB increased from 0.131 to 1.298 h −1 . The significant enhancement of visible photocatalytic activity was mainly attributed to folded nano-porous structure, which simultaneously improved visible-light absorption range and strength, and enlarged the band gap and specific surface area of g-C 3 N 4 .

The application of a porous silica (PS) transition layer in an inorganic-organic aeronautic laminated glass can effectively solve the material failure caused by the performance difference of the inorganic-organic materials. The effect of porous silica transition layer thickness on the mechanical and optical properties of laminated glass was investigated. The microstructure of the porous silica transition layer was analyzed by scanning electron microscopy. The film thickness was verified using a step profiler. The failure strength of laminated glass with the porous silica transition layer was tested by a universal testing machine. Finite element modeling of laminated glass with the porous silica transition layer was performed by ANSYS software. Tensile stress between the porous silica and the polyurethane was simulated for different porous silica film thicknesses. Experimental and theoretical results indicated that with the increasing the thickness of the transition film, the failure stress of the laminated glass increased. Improvements in the mechanical properties of the laminated glass are saturation at a PS thickness of approximately 3.8 μm. Keywords: Aeronautic laminated glass, Porous silica transition layer, Mechanical properties, Simulation

Carbon source precursors for high-grade, clean, and low-carbon refractories were obtained by in situ exfoliation of flake graphite (FG) and phenol&ndash, formaldehyde resin (PF) composites with three-roll milling (TRM) for the fabrication of graphite nanoplatelets. In addition, by using Ni(NO3)2&middot, 6H2O as a catalyst in the pyrolysis process, multidimensional carbon nanostructures were obtained with coexisting graphite nanoplatelets (GNPs), glassy carbon (GC), and carbon nanotubes (CNTs). The resulting GNPs (exfoliated 16 times) had sizes of 10&ndash, 30 &mu, m, thicknesses of 30&ndash, 50 nm, and could be uniformly dispersed in GC from the PF pyrolysis. Moreover, Ni(NO3)2&middot, 6H2O played a key role in the formation and growth of CNTs from a catalytic pyrolysis of partial PF with the V&ndash, S/tip growth mechanisms. The resulting multidimensional carbon nanostructures with GNPs/GC/CNTs are attributed to the shear force of the TRM process, pyrolysis, and catalytic action of nitrates. This method reduced the production costs of carbon source precursors for low-carbon refractories, and the precursors exhibited excellent performances when fabricated on large scales.

Electrochemical water splitting is considered to be one of the most potential strategies to achieve the hydrogen economy. In this paper, the porous NiMo alloys used as efficient electrocatalysts were designed and synthesized by microwave sintering powder metallurgy method. The as-prepared porous NiMo alloys as good electrocatalysts exhibit excellent hydrogen evolution reaction (HER) performance and outstanding durability in alkaline electrolyte (1.0 M KOH). Especially, the porous Ni6Mo4 alloy shows smaller overpotential of 37 mV at current density of 10 mA cm−2 and a low Tafel slope of 82.1 mV dec−1. The efficient electrocatalytic performance of Ni6Mo4 alloy can be attributed to the synergies of Ni, Mo and NiMo intermetallic compound, more active sites and quicker charge transfer rate.

While lithium-ion batteries (LIBs) have been widely used in commercial devices, finding suitable anode materials for alkali metal batteries is still challenging. Therefore, Ni3S2/Ni@N-doped carbon composite electrode was fabricated as the anode for alkali metal batteries. It was found that the Ni3S2/Ni@N-doped carbon electrode achieved a capacity of 742 mAh g−1 at the 1500th cycle at the current density of 1000 mA g−1 for LIBs, and obtained 275 mAh g−1 at the 250th cycle during 500 mA g−1 for Na+ storage. Moreover, it showed 52 mAh g−1 after 50 cycles at 100 mA g−1 for K+ storage. The excellent performances of this electrode is likely due to the combined effect of Ni and C layer. This work provides a simple approach approach for the design of high-performance materials that can be applied to commercial production as a potential substitute for the current alkali ion battery anodes.

Rational design of the photocatalysis is of vital importance to mediate many important photocatalytic reactions such as water splitting, pollutant degradation and CO2 reduction. In this work, we employed a solvent evaporation induced self-assembly method to prepare a novel S-scheme heterojunction composite by combining sulfur-doped porous graphite carbon nitride (S-pCN) with tungsten oxide (WO2.72) semiconductors which manifest effective interface contact and excellent photocatalytic performance. During the formation of the heterojunction, the electron defect state of surface oxygen vacancies on WO2.72 can be filled by the lone pair electrons of sulfur and nitrogen elements on S-pCN. Through the adjustment of composite ratios, appropriate surface oxygen vacancies were retained on WO2.72, thereby fascinate the migration of electrons and the generation of free radicals. The internal electric field (IEF) and the band bending effects accelerate the transfer of photogenerated charges at the interface, thereby promotes the recombination of useless photogenerated carriers, retains photogenerated electron (e−) and hole (h+) with the higher redox potentials, improves the separation and utilization efficiency of the photogenerated carriers and enhances the photocatalytic activity of the system. This work provides new insights for the design of a novel S-scheme heterojunction photocatalyst for highly efficient simultaneous photocatalytic degradation and hydrogen evolution activity.

Ni metal was directly used as raw materials to prepare Ni-gadolinia doped ceria (GDC) anode. In order to overcome the problems of agglomeration and oxidation of Ni particles in sintering, modified heterogeneous precipitation method and fast sintering technique were employed to prepare GDC coated Ni powders and Ni-GDC cermets. XRD, TG-DTA, SEM and AC impedance spectra measurements were applied to examining phase composition, oxidation, microstructure, and electrical property of GDC coated Ni powders and Ni-GDC composites. The results showed that GDC coated Ni powders were successfully synthesized by modified heterogeneous precipitation at pH = 7.7. Overhigh pH value resulted in the homogeneous precipitation (self-nucleation) of GDC that uncoated on Ni core. After coating, the oxidation temperature of sample was increased by 200 °C and the oxidation weight gain was decreased from 26.3% to 12.5% at 800 °C. With fast sintering at 1200 °C, Ni-GDC cermets sintered with 40 °C/min exhibited finer grains, lower impedance and larger hardness than that sintered with 10 °C/min and 80 °C/min.

γ-aluminium oxynitride (AlON) has an excellent thermal and chemical stability, which makes AlON an attractive candidate for a wide range of applications. Production of transparent AlON is extremely challenging because residual porosity must be reduced to an absolute minimum. This can be achieved by spark plasma sintering (SPS) and introducing sintering additives. This article provides a review of research activities that concentrate on the development of spark plasma reaction sintering of AlON ceramics with and without sintering additives. Influence of the most important operating parameters (atmosphere, temperature, processing time, heating rate, etc) on product characteristics and process dynamics is reviewed for AlON ceramics. Comparison of SPS over conventional methods including pressureless sintering, hot pressing sintering and others is demonstrated. Recent advances and challenges in the synthesis of AlON ceramics by SPS are also discussed.

One-dimensional SiO2@SiC shell–core nanowire was fabricated on a SiC substrate without any catalyst using a laser sintering method. Based on a solid–liquid–vapor–solid (SLVS) in situ growth mechanism, the as-synthesized SiO2@SiC nanowires of about 60 nm diameter with a shell thickness of about 13 nm were grown. Varying the power density of laser sintering allowed the final SiC particle morphology to be controlled from grainy to whisker-like. High power density or high temperature benefited the nucleation probability of SiC whiskers. The isothermal oxidation test showed that the SiO2@SiC nanowires have good thermodynamic stability at high temperature. The photoluminescence (PL) property of SiO2@SiC nanowire was also investigated. The observed emission peaks were composed of an UV peak centered at 365 nm (3.40 eV) and a blue peak centered at 453 nm (2.74 eV). The theory behind the PL property and the growth mechanism of the SiO2@SiC nanowire were also discussed.

Aluminum oxynitride (AlON) ceramic was fabricated by in-situ hot pressing sintering (HPS) from Al 2 O 3 and AlN doped with Y 2 O 3 and La 2 O 3 as well as without dopant for comparison. Dense AlON ceramic with a relative density of 99.7% was obtained by HPS doped with 0.4 wt% Y 2 O 3 and 0.1 wt% La 2 O 3 at 1700 °C for 4 h. The maximum fracture toughness of AlON ceramic with and without dopant was 3.74 MPa m 1/2 and 2.27 MPa m 1/2 , respectively. The maximum Vickers hardness of AlON ceramic with and without dopant was 18.3 GPa and 16.5 GPa, respectively. Compared with those of undoped AlON ceramic, the relative density and the fracture toughness of Y 2 O 3 -La 2 O 3 co-doped AlON ceramic were obviously improved. Overlarge grain size would reduce the Vickers hardness of AlON. The sintering activation energy of Y 2 O 3 -La 2 O 3 co-doped AlON was about 57% of that of undoped AlON. The sintering activity of AlON was highly improved by co-doping with Y 2 O 3 and La 2 O 3 .

Promoting in-situ growth on the Ni foam to form an integrated electrode could prove useful for improving the area-specific capacity and adhesion between the collector and active material. Here, a NiO/NiS2 nanosheet integrated electrode was designed and obtained by a hydrothermal method. The integrated electrode consisted of a mixture of NiS2 and NiO and was in the form of a nanosheet. The electrode showed high area-specific capacities as the anode for alkaline ion batteries and could achieve 1.51 (150th cycle), 0.93 (100th cycle), and 0.11 mAh•cm−2 (30th cycle) for Li+/Na+/K+ storage.

Due to the high price of noble metal catalysts, there is an urgent demand for the development of inexpensive and earth-abundant electrocatalysts for the oxygen evolution reaction (OER). It is known that a hierarchical structure can effectively increase the catalytic area and improve the charge transfer of the OER electrocatalyst, while Ni foam is known to be an advantageous substrate. Therefore, in this work a hierarchical Mn–CoO@Fe(OH)3 nanofiber array was prepared by the hydrothermal reaction and immersion at room temperature, and X-ray diffraction and transmission electron microscopy measurements were carried out to characterize the microstructure of the nanofiber array. X-ray photoelectron spectroscopy was used to analyze the valence states of the array, demonstrating the successful synthesis of the Mn–CoO@Fe(OH)3 nanofiber. As the catalyst for OER, the Mn–CoO@Fe(OH)3 nanofiber array showed a low overpotential of 195 mV at a current density of 10 mA cm−2 as well as high stability (80 h) in the durability test. This work demonstrates the feasibility of the design of hierarchical nanostructure electrodes with high electrochemical performance for catalytic reactions and various battery applications.

The spatial charge separation and explosion of high-active facets were considered as a pair entwined tactics for photocatalyst material with high ability. Herein, Ag3PO4/BiVO4 was controllably fabricated by selectively deposited Ag3PO4 on the high-active (0 4 0) facets of BiVO4. The photocatalytic activities of Ag3PO4/BiVO4 in degradation TCH was approximately 8.8 and 5.7 times than that of BiVO4 and Ag3PO4, accordingly. Furthermore, the mineralization rate of TCH over Ag/Bi4 (0 4 0) could reach to 91% after irradiated 180 min. After systematic characterization, the built-in electric field in Ag3PO4/BiVO4 was produced by the interfacial interaction between Ag3PO4 and BiVO4, which served as a charge carrier space that facilitated the transfer and separation of photogenerated carriers. Therefore, the spatial charge separation, explosion of high-active facets of BiVO4 and interfacial effects between Ag3PO4 and BiVO4 were in favor of high catalytic activity.

Reduced graphene oxide modified black phosphorus quantum dots (rGO@BPQDs) were obtained through surface modification of BPQDs with rGO via an ultrasound-assisted liquid phase method. The rGO@BPQDs could effectively enhance the chemical and structural stability of BPQDs. Zero-dimension rGO@BPQDs were firmly anchored on mesoporous g-C3N4 (CN) via a self-trapping pore confinement effect and π-π interactions to form CN/rGO@BPQDs, which remarkably improved the photoelectric properties of CN. The responsive wavelength of CN/rGO@BPQDs could be extended to 800 nm. The kinetic constant of Rhodamine B and tetracycline degradation reached 0.183 and 0.0194 min−1, respectively. The H2O2 production rate of CN/rGO@BPQDs was 2.6 times that of porous CN. The improved photocatalytic performance and remarkable increase in free radicals are attributed to the formation of n-n type high-low junctions as well as the internal electric field based on different Fermi levels between CN and BPQDs. These collectively promote spatial separation of photogenerated carriers.

In this work, the effect of MgO addition on the sinterability and crystallization of sintered glass–ceramics prepared from powder mixtures of waste glass and fly ash was investigated. The bulk density of the glass–ceramics decreased with increasing the MgO content, reaching the maximum value at the sintering temperature of 1000 °C. The amounts of the glass-ceramic crystalline phases, i.e., pyroxene and forsterite, increased with the MgO content. Furthermore, when the MgO content increased from 5 to 25 wt%, the crystallization mechanism changed from bulk to surface crystallization. The flexural strength was significantly influenced by three factors, i.e., porosity, crystallinity, and crystal shape anisotropy, and reached the maximum value of 78 MPa for a 10 wt% content of MgO. Fast sintering promoted the densification process, thus increasing the glass-ceramic flexural strength. As a result, owing to their high strength and relatively low density, these sintered glass–ceramics appear promising for potential applications in lightweight construction tiles.