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Solar energy is a key sustainable energy resource, and materials with optimal properties are essential for efficient solar energy‐driven applications in photocatalysis. Metal–organic frameworks (MOFs) are excellent platforms to generate different nanocomposites comprising metals, oxides, chalcogenides, phosphides, or carbides embedded in porous carbon matrix. These MOF derived nanocomposites offer symbiosis of properties like high crystallinities, inherited morphologies, controllable dimensions, and tunable textural properties. Particularly, adjustable energy band positions achieved by in situ tailored self/external doping and controllable surface functionalities make these nanocomposites promising photocatalysts. Despite some progress in this field, fundamental questions remain to be addressed to further understand the relationship between the structures, properties, and photocatalytic performance of nanocomposites. In this review, different synthesis approaches including self‐template and external‐template methods to produce MOF derived nanocomposites with various dimensions (0D, 1D, 2D, or 3D), morphologies, chemical compositions, energy bandgaps, and surface functionalities are comprehensively summarized and analyzed. The state‐of‐the‐art progress in the applications of MOF derived nanocomposites in photocatalytic water splitting for H2 generation, photodegradation of organic pollutants, and photocatalytic CO2 reduction are systemically reviewed. The relationships between the nanocomposite properties and their photocatalytic performance are highlighted, and the perspectives of MOF derived nanocomposites for photocatalytic applications are also discussed. The state‐of‐the‐art progress in the production of metal–organic framework (MOF) derived nanocomposites with various dimensions (0D, 1D, 2D, or 3D), morphologies, chemical compositions, energy bandgaps, and surface functionalities are comprehensively summarized and analyzed. The photocatalytic applications of those MOF derived nanocomposites in photocatalytic water splitting for H2 generation, photodegradation of organic pollutants, and photocatalytic CO2 reduction are systemically reviewed.

Revolutionary changes in energy storage technology have put forward higher requirements on next‐generation anode materials for lithium‐ion battery. Recently, a new class of materials with complex stoichiometric ratios, high‐entropy oxide (HEO), has gradually emerging into sight and embracing the prosperity. The ideal elemental adjustability and attractive synergistic effect make HEO promising to break through the integrated performance bottleneck of conventional anodes and provide new impetus for the design and development of electrochemical energy storage materials. Here, the research progress of HEO anodes is comprehensively reviewed. The driving force behind phase stability, the role of individual cations, potential mechanisms for controlling properties, as well as state‐of‐the‐art synthetic strategies and modification approaches are critically evaluated. Finally, we envision the future prospects and related challenges in this field, which will bring some enlightening guidance and criteria for researchers to further unlock the mysteries of HEO anodes. The ideal elemental adjustability and appealing synergistic effects have led high‐entropy oxide (HEO) to attract growing scientific interest as anode for Li‐ion batteries. This article provides some enlightening guidelines and criteria for further unlocking the mystery of HEO anodes through an overview of their current status and specific descriptions regarding material design and electrochemical behavior.

The rational design of nanomaterials with distinct exposed facets is of great importance for improving the physicochemical properties of these materials and for the study of structure–activity relationships. This work describes the first synthesis of lanthanum titanate (La2Ti2O7, LTO) with dandelion-like nanostructures via the molten salt method. The lowest synthesis temperature of 700 °C is at least 200 °C lower than that required by other methods. The dandelion structure consists of well-crystallized LTO nanorods (NRs) with sizes of less than 100 nm in the radial direction and 300–500 nm in the axial direction, which is different from the widely accepted two-dimensional form. LaOCl microplates were formed as an intermediate substrate for LTO NR growth outwards to the basal surfaces of the LaOCl crystallites. DFT calculation results showed that the strong LiCl adsorption on the (100) surface led to distinct growth of the (100) and (020) planes, thus promoting the rod-like growth of LTO along the [010] axis. In addition, the photocatalytic performance of as-prepared LTO was evaluated by determining the degradation of rhodamine B. The results suggested that the as-prepared LTO could markedly enhance the photocatalytic activity as a result of the surface heterojunction of coexposed 100 and 002 facets in LTO NRs.Nanomaterials: photocatalysts take a cue from dandelionsA catalyst that uses light irradiation to decompose organic pollutants can become more active by being fabricated into rod-like nanostructures resembling dandelion seeds. Zhong Huang from the Wuhan University of Science and Technology in China and co-workers have developed a method for synthesizing lanthanum titanate, a ceramic that excels at separating positive and negative photogenerated charges so they can be employed for catalytic reactions. The team’s approach quickly prepares lanthanum titanate nanocrystals using a bath of molten lithium and potassium salts. By optimizing the molten salt concentrations, the researchers isolated tiny aggregates of nanorods that have a high number of exposed crystal facets for charge separation. Experiments showed the nanorods could degrade model pollutants such as rhodamine dyes several times faster than conventional plate-shaped lanthanum titanates.

Corundum-spinel based purging plugs are extensively employed in steel ladle refining processes. Traditionally, these plugs are manufactured through a high-temperature firing process that not only demanded substantial energy consumption but also resulted in a dense microstructure with higher strength; however, they often led to undesirable consequences such as fracture and thermal spalling, significantly impeding the enhancement of their service life. In recent years, the steel industry has witnessed the emergence of unfired purging plugs as an alternative solution. Unfortunately, there are some shortcomings including low strength at intermediate-temperature and poor volume stability, which easily lead to a short life and lower blowing rate of the unfired purging plug, thereby restricting their utilization. Aiming to improve the intermediate-temperature properties of the unfired purging plug, the effect of Zn(OH)2 on the properties of the castables was investigated. The results show that the cold strength of the specimens sintered at different temperatures remarkably increased with rising Zn(OH)2 content, for instance, CMOR values of the specimens sintered at 800 °C escalated from 3.19 MPa to 14.98 MPa. Furthermore, the incorporation of Zn(OH)2 led to a reduction in permanent linear change and a marked increase in hot strength. The remarkable improvement in intermediate-temperature strength can be attributed to the formation of ZnCr2O4 and ZnAl2O4 spinel phases originating from the reaction between ZnO derived from the decomposition of Zn(OH)2, and the existing Cr2O3 or Al2O3. These spinel phases create a reinforcing effect, thereby substantially enhancing the mechanical properties of the specimens after firing at intermediate temperatures.

Corundum–MgAl2O4 spinel-based castables bonded with calcium aluminate cement (CAC) and hydratable alumina (HA) were studied to evaluate their performance as gas purging plugs in steel ladles. The thermomechanical properties and corrosion behavior of the as-prepared castables were investigated. The results indicate that the cold crushing strength and modulus of rupture of castables bonded with CAC and HA after firing at 1600 °C are in the same levels of 160 and 32 MPa, respectively. The sample bonded with HA showed lower permanent change of − 0.23 pct and slag infiltration index of 0.07 compared with CAC-bonded samples (> 0.34 pct and > 0.36, respectively), suggesting the better volume stability and corrosion and slag infiltration resistance to CaO–SiO2–Fe2O3–Al2O3-based slag of HA-bonded castable. The in situ-formed MgAl2O4 spinel changed the corrosion and infiltration indices of CAC-bonded castable to 0.09 and 0.39, respectively, compared with castable without in situ MgAl2O4 spinel, indicating that the corrosion resistance was improved but the infiltration resistance was reduced by the in situ-formed MgAl2O4 spinel.

Frequent offshore oil spill accidents, industrial oily sewage, and the indiscriminate disposal of urban oily sewage have caused serious impacts on the human living environment and health. The traditional oil-water separation methods not only cause easily environmental secondary pollution but also a waste of limited resources. Therefore, in this work, three-dimensional (3D) graphitic carbon sphere (GCS) foams (collectively referred hereafter as 3D foams) with a 3D porous structure, pore size distribution of 25–200 µm, and high porosity of 62vol% were prepared for oil adsorption via gel casting using GCS as the starting materials. The results indicate that the water contact angle (WCA) of the as-prepared 3D foams is 130°. The contents of GCS greatly influenced the hydrophobicity, WCA, and microstructure of the as-prepared samples. The adsorption capacities of the as-prepared 3D foams for paraffin oil, vegetable oil, and vacuum pump oil were approximately 12–15 g/g, which were 10 times that of GCS powder. The as-prepared foams are desirable characteristics of a good sorbent and could be widely used in oil spill accidents.

In this work, carbon nanotubes (CNTs) were synthesized by catalytic pyrolysis from waste polyethylene in Ar using an in-situ catalyst derived from ferric nitrate and nickel nitrate precursors. The influence factors (such as temperature, catalyst content and Fe/Ni molar ratio) on the formation of CNTs were investigated. The results showed that with the temperature increasing from 773 to 1073 K, the carbon yield gradually increased whereas the aspect (length-diameter) ratio of CNTs initially increased and then decreased. The optimal growth temperature of CNTs was 973 K. With increasing the Fe/Ni molar ratio in an FeNi bimetallic catalyst, the yield of CNTs gradually increased, whereas their aspect ratio first increased and then decreased. The optimal usage of the catalyst precursor (Fe/Ni molar ratio was 5:5) was 0.50 wt% with respect to the mass of polyethylene. In this case, the yield of CNTs reached as high as 20 wt%, and their diameter and length were respectively 20–30 nm, and a few tens of micrometers. The simple low-cost method developed in this work could be used to address the environmental concerns about plastic waste, and synthesize high value-added CNTs for a range of future applications.

Loading a noble metal on Bi4Ti3O12 could enable the formation of the Schottky barrier at the interface between the former and the latter, which causes electrons to be trapped and inhibits the recombination of photoelectrons and photoholes. In this paper, AgPt/Bi4Ti3O12 composite photocatalysts were prepared using the photoreduction method, and the effects of the type and content of noble metal on the photocatalytic performance of the catalysts were investigated. The photocatalytic degradation of rhodamine B (RhB) showed that the loading of AgPt bimetallic nanoparticles significantly improved the catalytic performance of Bi4Ti3O12. When 0.10 wt% noble metal was loaded, the degradation rate for RhB of Ag0.7Pt0.3/Bi4Ti3O12 was 0.027 min−1, which was respectively about 2, 1.7 and 3.7 times as that of Ag/Bi4Ti3O12, Pt/Bi3Ti4O12 and Bi4Ti3O12. The reasons may be attributed as follows: (i) the utilization of visible light was enhanced due to the surface plasmon resonance effect of Ag and Pt in the visible region; (ii) Ag nanoparticles mainly acted as electron acceptors to restrain the recombination of photogenerated electron-hole pairs under visible light irradiation; and (iii) Pt nanoparticles acted as electron cocatalysts to further suppress the recombination of photogenerated electron-hole pairs. The photocatalytic performance of Ag0.7Pt0.3/Bi4Ti3O12 was superior to that of Ag/Bi4Ti3O12 and Pt/Bi3Ti4O12 owing to the synergistic effect between Ag and Pt nanoparticles.

Titanium carbide ultrafine powders were prepared from tetrabutyl titanate and sucrose by sol–gel and microwave carbothermal reduction. The influences of reaction temperature and molar ratio of Ti to C on the synthesis of titanium carbide were studied. The results show that excess amount of carbon plays a positive effect on the carbothermal reduction of TiO 2 at low temperature. The inceptive carbothermal reduction temperature of TiO 2 and formation of titanium oxycarbide was below 900 °C, and pure TiC can be prepared at 1,200 °C, which was considerably lower compared to that by conventional carbothermal reduction using a mixture of TiO 2 and carbon powders as raw materials. The morphology and particle size of synthesized TiC powder were examined by field emission-scanning electron microscopy (FE-SEM) and the quantities of the phases of the powders were analyzed by Rietveld refinement method, the particle sizes of the TiC powders synthesized at 1,300 °C distribute over 0.1–0.5 μm.

Recently, developing a cost-effective and high-performance catalyst is regarded as an urgent priority for hydrogen generation technology. In this work, ISOBAM-104 stabilized Co/Fe colloidal catalysts were prepared via a co-reduction method and used for the hydrogen generation from KBH4 hydrolysis. The obtained ISOBAM-104 stabilized Co10Fe90 colloidal catalysts exhibit an outstanding catalytic activity of 37,900 mL-H2 min−1 g-Co−1, which is far higher than that of Fe or Co monometallic nanoparticles (MNPs). The apparent activation energy (Ea) of the as-prepared Co10Fe90 colloidal catalysts is only 14.6 ± 0.7 kJ mol−1, which is much lower than that of previous reported noble metal-based catalysts. The X-ray photoelectron spectroscopy results and density functional theory calculations demonstrate that the electron transfer between Fe and Co atoms is beneficial for the catalytic hydrolysis of KBH4.