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The efficiency of track utilization is one of the important factors for train operation in marshalling stations, and it can not only affect the turnover efficiency of trains, but also determine the capacity of railway stations. This paper presents an optimization method for track utilization in the arrival yard of a marshalling station considering Arrival and Break-up Coordination Operation (ABCO). The interaction between the push operation of trains and track utilization efficiency is investigated. First, the case of crossing the running route for shunting locomotives is analyzed. Whether the shunting route crosses or not can greatly affect the duration of trains occupying tracks in the station. Then, a nonlinear integer programming model (NLPM) is established based on the above analysis. The ultimate goal is to minimize the number of crossovers of the shunting route by adding a constraint condition for ensuring traffic safety. A track assignment algorithm based on ABCO for solving the NLPM is proposed. Train operations in the downlink arrival yard of station A are simulated with the proposed method. The results after applying the optimization method show that the average duration of trains on the tracks is reduced by 49.1%, and the degree to which tracks utilization is balanced is also significantly improved. The proposed method optimizes and extends the current achievements that have been reported in the literature. [ABSTRACT FROM AUTHOR]

A desalination device based on wood-derived aerogel after a simple surface carbonization treatment was reported, which can absorb sunlight to generate steam and resist salt accumulation even in high-concentration brine with a high evaporation rate of 1.40 kg m−2 h−1 and a high evaporation efficiency of 83.4% in seawater. [Display omitted] • A solar interface evaporator derived from wood was designed for steam generation. • The preparation of evaporator only requires simple carbonization on the surface. • The device gains evaporation rate of 1.4 kg m−2 h−1 and efficiency of 83.4%. • The device has excellent salt resistance and self-salt discharge capacity. Interface solar-driven evaporation is a very promising technology used in solar energy harvesting, seawater desalination and water purification. However, salt accumulation is still a serious problem that hinders the long-term stable operation of the evaporator. Herein, we use natural wood with inherent porosity to develop a flexible cellulose aerogel, which can be used as efficient and stable solar evaporator for desalination after simple surface carbonization. This aerogel evaporator achieves a solar steam efficiency of 83.4% and an evaporation rate of 1.40 kg m−2 h−1 under the sunlight intensity of 1 kW m−2. In the simulated evaporation experiment for 7 days, the evaporator shows a stable evaporation rate (about 1.39 kg m−2 h−1), indicating the potential for long-term operation. In addition, the evaporator has the ability to resist salt accumulation and self-cleaning. The low cost, simple preparation and multiple functions make the evaporator promising to be a continuous and stable installation for solar desalination. [ABSTRACT FROM AUTHOR]

The anionic uranyl-organic framework not only effectively adsorbs diquat herbicide through electrostatic and π-π stacking interactions, but also possesses semiconductor-like properties that allow for the harmless and complete removal of diquat by photocatalytic degradation. [Display omitted] • Synthesis of a novel light-sensitive three-dimensional uranyl-organic framework with anionic skeleton was achieved. • The compound can serve as both efficient absorbent and photocatalyst for the removal of diquat. • The adsorption and degradation removal ratio for diquat can reach 100%. • The compound can be regenerated and reused under light irradiation after adsorption of diquat. Adsorption and photocatalysis are generally considered an environmental friendliness and effective methods for eliminating organic pollutants. Developing bifunctional materials that integrate adsorption and photocatalysis can fully leverage the adsorption effect to increase the interaction between herbicides and photocatalysts, thus improving their photocatalytic degradation efficiency. To achieve the absorption and photocatalytic activity on contaminants, a light-sensitive three-dimensional uranyl-organic framework (UOF) named HNU-80 with an anionic skeleton was synthesized in this work. The charge characteristics of its electrostatic attraction with cations and the suitable band structure for producing reactive oxygen endow it with the potential for efficient adsorption and photocatalytic oxidation of the cationic diquat herbicide. The maximum adsorption capacity is up to 97.92 mg·g−1, and the adsorbed diquat could be completely degraded under light irradiation. In addition, the regenerated HNU-80 exhibits high reusability in subsequent adsorption cycle experiments. The adsorption mechanism is attributed to the electrostatic and π...π interaction between HNU-80 and diquat, while the photodegradation mechanism is due to the oxidation and decomposition of diquat by reactive oxygen species generated from the radiation of HNU-80. This work provides a promising candidate for the harmless treatment of organic pollutants, and the combination of photocatalytic property also promotes the regeneration of the UOF adsorbents for continued use. [ABSTRACT FROM AUTHOR]

At present, catalysts play an important role in modern industries, and there are 80 percent of industrial reactions need the participation of catalysts. Noble metal catalysts have significant applications in many fields because of the high selectivity, fine stability and excellent reactivity. However, the large‐scale applications of noble metal are limited by the high price. Preparing noble metal catalysts as small as possible or even in single atom dispersion, can effectively improve the atomic, which partly solves the problem of high price. Nevertheless, this will lead to another problem that the surface free energy increases quickly when the size of noble metal decreases, resulting in the aggregation of noble metal. To address this issue, a suitable support is needed to fix noble metal. CeO2, as an ideal supporting material, has received widespread attention due to the excellent properties including two valences which are easy to interconvert, high oxygen storage capacity and a large number of oxygen deficiencies. So far, the ultra‐small noble metal ceria‐based catalytic materials have been widely developed in many catalysis fields, such as CO oxidation, water‐gas shift reactions, hydrogenation reaction, etc. In this review, the controlled preparations, influence factors and applications of ultra‐small noble metal supported on CeO2 carrier are introduced. Besides, the developments and challenges of this field are proposed. [ABSTRACT FROM AUTHOR]

Abstract Two heteronuclear clusters-based MOFs, CoLi(HL)·4DMA (HNU-23) and CoLi 2 (L)(DMF) 2 ·DMF·H 2 O (HNU-24) (H 4 L = 5- [bis(4-carboxybenzyl) amino] isophthalic acid) were successfully synthesized through a solvent-directed strategy. The luminescence sensing property investigations reveal that HNU-23 and HNU-24 exhibit turn-on luminescence towards the H+ concentration under strong acidic condition, and could be served as potential pH sensors. HNU-23 shows high linear H+ concentration response in the range of 0.02–0.2 M; HNU-24 exhibits similar linear response towards the H+ concentration from 0.1 to 0.2 M. The mechanism of this sensing behavior can be explained through disruption of the HNU-23 and HNU-24 structures under acidic condition to gradually release the fluorophore. Graphical abstract Two fascinated metal-organic frameworks constructed from tetranuclear and hexanuclear heterometallic clusters, respectively, are synthesized by a solvent-directed strategy, which can serve as efficient luminescent pH sensors under strong acidic condition. fx1 [ABSTRACT FROM AUTHOR]

Herein, Cu3P was used as a co-catalyst to improve the separation efficiency of photogenerated carriers in WSe2 photocatalysts. The metallic nature of Cu3P and its noble metal-like properties make it an affordable and efficient co-catalyst. The experimental results revealed that the photocatalytic activity of the WSe2/Cu3P (WP) sample was significantly higher under visible light with an average hydrogen evolution rate (HER) of 616.50 μmol h−1 g−1 and a quantum yield of 23.75%. In contrast, the average HER of the pure WSe2 sample was only 298.46 μmol h−1 g−1. The preparation parameters were optimized by a single-factor test. The optimal preparation parameters were as follows. The loading of Cu3P was 8%, and the calcination time and temperature were 2.0 h and 300 °C, respectively. An innovative exploration of the photocatalytic memory effect of WP photocatalyst was carried out. The analysis of the experimental results displayed that the HER of the WP photocatalyst under dark conditions reached 418.50 μmol h−1 g−1 after 5.0 h post-illumination. [ABSTRACT FROM AUTHOR]

The semiconductor-like characteristics and light absorption ability of metal-organic frameworks (MOFs) make it have the potential for photoelectrochemical sensing. Compared with composite and modified materials, the specific recognition of harmful substances directly using MOFs with suitable structures can undoubtedly simplify the fabrication of sensors. Herein, two photosensitive uranyl-organic frameworks (UOFs) named HNU-70 and HNU-71 were synthesized and explored as the novel "turn-on" photoelectrochemical sensors, which can be directly applied to monitor the biomarker of anthrax (dipicolinic acid). Both sensors have good selectivity and stability towards dipicolinic acid with the low detection limits of 1.062 and 1.035 nM, respectively, which are far lower than the human infection concentration. Moreover, they exhibit good applicability in the real physiological environment of human serum, demonstrating a good application prospect. Spectroscopic and electrochemical studies show that the mechanism of photocurrent enhancement results from the interaction between dipicolinic acid and UOFs, which facilitates the photogenerated electron transport. The combination of uranyl-organic frameworks with dipicolinic acid will enhance the photocurrent intensity to achieve the photoelectrochemical detection of dipicolinic acid. [Display omitted] • Design and synthesis of two novel light-sensitive three-dimensional uranyl-organic frameworks. • Two compounds can serve as efficient photoelectrochemical probes for dipicolinic acid. • The limit of detection can be as low as 1.035 nM with high selectivity. • The practicability of detection in real environment is further verified by human serum experiment. [ABSTRACT FROM AUTHOR]

The construction of heterojunction photocatalysts is an effective strategy to improve photocatalytic activity. Inspiringly, this is studied by the successful fabrication of new composites of a robust Zr-MOF and low-cost g-C3N4via a simple method of mechanical grinding followed by low-temperature heating. The synthesized composites exhibit characteristics of wide-range visible-light absorption, good long-term stability and significant photocatalytic hydrogen production. The optimal H2 production rate of the Zr-MOF/g-C3N4 (5.0 wt%) heterojunction was 1.252 mmol h−1 g−1, which was 41.7 and 15.7 times higher than that of pure Zr-MOF and g-C3N4, respectively. The Z-scheme charge transfer mechanism in Zr-MOF/g-C3N4 effectively improves charge separation and maintains its high redox ability, thus greatly enhancing photocatalytic hydrogen production activity. This study presents the rational fabrication of heterojunctions for photocatalytic applications and also provides new high-performance and low-cost MOF/g-C3N4 photocatalysts for H2 production. [ABSTRACT FROM AUTHOR]

The magnetic nanocomposite Fe3O4@ZIF-8 was for the first time used as an excellent adsorbent for the fast adsorption and separation of UO22+ ions from aqueous solutions. This material exhibited an unprecedented adsorption capacity of 523.5 mg U per g and a remarkable selectivity towards UO22+/Ln3+ at pH = 3. [ABSTRACT FROM AUTHOR]

Rational selection and modification of rare earth metal centers and photoactive organic linkers enables designable multiphotofunctionality to come to fruition in new hybrid coordination polymer materials. By using a viologen-functionalized diphosphonate linker, two terbium phosphonate compounds ( Tb-1 and Tb-2) have been constructed, which display reversible photochromic reactions in response to UV light and soft X-ray irradiation. In addition, the photo-induced electron-transfer reaction can modulate the luminescent emission to thus realize photoluminescence switching behavior. Furthermore, both terbium phosphonates can serve as highly sensitive sensors to probe Cu2+ in solution through their luminescence. Thus, they represent the first photochromic examples of lanthanide phosphonate-based materials with photomodulated luminescence and sensitive detection of metal ions. [ABSTRACT FROM AUTHOR]

Uranium phosphonates, an important class of actinide-organic coordination polymers, exhibit an exceptionally diverse and broad range of crystal structures. A variety of structure topologies have been identified for hexavalent uranium phosphonates, including cage clusters, chains, ribbons and tubes, sheets, and three-dimensional frameworks. In contrast, only a handful of tetravalent uranium phosphonates are known. This review presents a comprehensive account of the crystal structures of uranium phosphonates and the various building units ( e.g. discrete monomers, polymeric units, infinite chains, and sheets) that result from the numerous coordination modes of phosphonate ligands with uranium. [ABSTRACT FROM AUTHOR]

Reaction of uranyl dications with (2-carboxyethyl)(phenyl)phosphinic acid (CPPA, H2L) under hydrothermal conditions gave two layered isomers (UO2)2(L)2, namely, CPP-U1 and CPP-U2. Both of them feature edge-sharing uranyl dimers as structure-building units, which are ligated by CPP ligands in different ways, thus leading different layered arrangements. With the addition of imidazole derivatives, two three-dimensional structures UO2(L)(dib)0.5 (CPP-U3) and UO2(L)(bbi)0.5 (CPP-U4) were generated, in which the similar uranyl-phosphinate layers are connected by two different imidazole derivatives by means of the U-N connection [dib = 1,4-di(1 H-imidazol-1-yl)benzene; bbi = 1,1′-(1,4-butanediyl)bis(imidazole)]. The syntheses, structure, as well as the IR spectra, and luminescent and photocatalytic properties of these uranyl organophosphinates are reported in this paper. [ABSTRACT FROM AUTHOR]

Spent catalysts of selective catalytic reduction (SCR) contain a high content of TiO 2 (>70 wt%). The effective recovery of TiO 2 from spent SCR catalysts and its reuse in photocatalytic hydrogen production is of great importance for environmental protection. In this study, the recovered TiO 2 from the spent SCR catalyst was recovered by the alkali washing method, and the purity of the recovered TiO 2 reached 94.7%. g-C 3 N 4 as a co-catalyst and enhanced the separation efficiency of the photogenerated electron-hole pairs of the TiO 2 photocatalyst. The composite photocatalyst R–TiO 2 /g-C 3 N 4 prepared by directly mixing the recovered TiO 2 with g-C 3 N 4 significantly improved the photocatalytic activity. The experimental design of the photocatalyst synthesis was optimized using the Design Expert software. The results showed that the recovered TiO 2 was 0.334 g when the g-C 3 N 4 was 0.046 g and the ultrasonic time was 163 min. Moreover, the hydrogen production rate reached 443.105 μmol g−1 h−1 within 4 h. [Display omitted] • Successfully and effectively recovered TiO 2 from the spent SCR catalyst. • The addition of g-C 3 N 4 increased the H 2 production rate of the recovered TiO 2 (421.445 μmol g−1 h−1). • The optimum preparation conditions of TiO 2 /g-C 3 N 4 catalyst were determined by using Design Expert software. [ABSTRACT FROM AUTHOR]

Five novel zinc uranyldiphosphonates have been hydrothermallysynthesized by using a series of flexible diphosphonate ligands, includingethane-1,2-diyldiphosphonic acid (H4EDP), propane-1,3-diyldiphosphonicacid (H4PDP), and butane-1,4-diyldiphosphonic acid (H4BDP). Compound Zn(H2tib)(UO2)2(EDP)(HEDP)(H2EDP)0.5·3H2O(EDP-ZnU1, tib = 1,3,5-tri(1H-imidazol-1-yl)benzene)comprises dimeric U2O12unit condensed by twoUO7pentagonal bipyramids, which are further connectedby Zn-centered polyhedra and EDP ligands resulting in a 3-dimensionalframework. Compound [Zn(bipy)(H2O)](UO2)(PDP)(PDP-ZnU1, bipy = 2,2′-bipyridine) also featuresU2O12dimers and Zn-centered polyhedra, buta layered arrangement is formed. Different from that in PDP-ZnU1, the uranium exists in the form of UO6tetragonal bipyramidand is surrounded by four PDP ligands to generate the layered structureof Zn(bipy)(UO2)(PDP) (PDP-ZnU2). ZnO2N2tetrahedra are connected on both sides of thelayers. Both Zn2(phen)4(UO2)3(BDP)(HBDP)2·4H2O (BDP-ZnU1, phen = 1,10-phenanthroline) and Zn2(bipy)2(UO2)3(HBDP)2(H2BDP)2(BDP-ZnU2) contain U2O12dimers and UO6tetragonal bipyramids. In BDP-ZnU1, uranyl centers are bridged by BDP to form a 2-dimensional structure,on which Zn(phen)2are decorated. Whereas in BDP-ZnU2, uranyl phosphonate layers are connected by bridging ZnO3N2to produce framework structure. All of these compoundshave been investigated by IR and photoluminescent spectroscopy. Theircharacteristic green light emissions have been attributed to transitionproperties of uranyl dications. [ABSTRACT FROM AUTHOR]

Three ZnII metal-organic frameworks (Zn-MOFs), [Zn2(tib)(HL1)(H2L1)0.5]⋅2H2O ( 1), [Zn2(tib)(L2)]⋅H2O ( 2) and [Zn3(tib)(L3)2(H2O)6]⋅2 H2O ( 3), have been prepared by reactions of 1,3,5-tris(1-imidazolyl)benzene (tib), and biphenyl-3,3′,4,4′-tetracarboxylic acid (H4L1), 4,4′-oxydiphthalic acid (H4L2), or benzene-1,3,5-tricarboxylic acid (H3L3) with corresponding ZnII salts, respectively. Single crystal structure analyses reveal that 1 and 2 are constructed by Zn-centered polyhedra, tib and multidentate tetracarboxylate ligands to form 3-dimensional frameworks. In contrast, when the tetracarboxylate ligands were replaced by tricarboxylate ligand, layered structure of 3 is produced. These compounds are further characterized by powder X-ray diffraction, element analyses, thermogravimetric analyses and photoluminescent spectroscopy. The luminescent properties of three Zn-MOFs dispersed in different solvents have been investigated systematically, demonstrating high sensitivity for the detection of nitro compounds via a fluorescence quenching mechanism. [ABSTRACT FROM AUTHOR]

Solvothermal assembly of Co(II) ion, a semirigid tetrahedralcarboxylateligand tetrakis[(4-carboxyphenyl)oxamethyl]methane acid (H4L), and rigid linear bidentate linker 1,4-di(1H-imidazol-1-yl)benzene(dib) or 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl(dibp) yields four novel metal–organic frameworks (1–4) with different topological connections. [Co2(L)(dib)]·3DMF (1) is a 2-fold interpenetrating sqc422 network and contains 3-dimensional interconnectedchannels along [100], [010], and [110] directions; [Co4(L)2(dib)3(H2O)4]·4H2O (2) is a three-dimensional 3,4,4-connectednew topology with 5-fold interpenetration; [Co2(L)(dibp)]·5DMF(3) and Co2(L)(dibp)2(4) are formed in the presence of dibp linker; they feature three-dimensionalnovel topologies based on 4,6-connection and 4,4-connection, respectively,and no interpenetration is observed. It is demonstrated that interpenetrationis accessible simply by changing auxiliary ligands and solvents. Magneticstudies reveal that complexes 1and 3exhibitantiferromagnetic behavior. [ABSTRACT FROM AUTHOR]

Photo-functionalized metal–organic frameworks (PMOFs) have attracted extensive attention recently because of their intrinsic structures and rich fluorescent components, showing unique advantages and broad application prospects in optical anti-counterfeiting. This review introduces the latest progress of PMOFs for different levels of anti-counterfeiting applications. The construction strategies of PMOFs are summarized, and the different levels of optical anti-counterfeiting based on PMOFs under various stimulation modes are discussed. In addition, we briefly discuss the existing challenges and prospects of PMOFs in anti-counterfeiting applications. It is hoped that this review will provide new insights and guidance for optical anti-counterfeiting. [ABSTRACT FROM AUTHOR]

Hydrothermal reactions of zinc uranyl acetate and 1-hydroxyethylidenediphosphonicacid (H4L) with 1,10-phenanthroline (phen), 2,2′-bipyridine(bipy), 1H-benzo[d]imidazole (bi),or 1-phenyl-1H-imidazole (pi) resulted in the formationof four new zinc uranyl compounds, namely, [Zn2(phen)2(UO2)2(L)2(H2O)3]·3H2O (ZnUP-1), Zn2(bipy)2(UO2)2(L)2(H2O)2(ZnUP-2), (Hbi)[Zn0.5(UO2)2(L)(H2L)(H2O)3]·3H2O (ZnUP-3), and (Hpi)[Zn(UO2)2(H2O)4(L)(HL)]·H2O (ZnUP-4). These four structures all compriseuranyl diphosphonate layers formed by UO7pentagonal bipyramidsand PO3C tetrahedra. Such layers are further connectedby Zn-centered polyhedra by sharing oxygens from phosphonate groups.For ZnUP-1and ZnUP-2, the zinc atoms areterminally coordinated by phen and bipy molecules, respectively, resultingin two-dimensional (2-D) hybrid materials. In ZnUP-3and ZnUP-4, the uranyl phosphonate layers are joined togetherby Zn–O polyhedra forming three-dimensional (3-D) frameworks.The structures of ZnUP-3and ZnUP-4containlarge channels along the a-axis with apertures around3.4 × 13.3 and 4.4 × 12.2 Å2, respectively.Protonated templates exist in the channels, filling the space andcompensating the negative charge of the anionic frameworks. Photoluminescentstudies reveal that ZnUP-1and ZnUP-2exhibitthe characteristic vibronically coupled charge-transfer based UO22穨겲⨧. [ABSTRACT FROM AUTHOR]

Abstract: Three new isostructural organo-templated transition metal borophosphates, (C3H12N2)[MnB2P3O12(OH)] (denoted MnBPO-CJ30), (C3H12N2)[FeB2P3O12(OH)] (denoted FeBPO-CJ30A) and (C4H12N2)[FeB2P3O12(OH)] (denoted FeBPO-CJ30B) were hydrothermally synthesized by using 1,2-diaminopropane and piperazine as the template, respectively. Single-crystal X-ray diffraction analyses reveal that the framework of MBPO-CJ30 (M=Mn, Fe) is constructed from the connection of infinite loop-branched borophosphate [B2P3O12(OH)4−] chains and MO6 octahedra, giving rise to three-dimensional (3-D) intersecting 8-, 8- and 9-ring channels along the [011], [01] and [100] directions, respectively. The negative charge of the framework is compensated by the diprotonated 1,2-diaminopropane or piperazine cations located in the 9-ring channels. These compounds are further characterized by powder X-ray diffraction, ICP, CHN, TGA, IR, and magnetic measurement. Structural analyses reveal that the organic amines that have the similar structure-directing ability but differing in size and shape have an influence on the crystal symmetry as well as the pore shapes of the 9-ring channels of these isostructures. Magnetic studies reveal that MnBPO-CJ30 exhibit antiferromagnetic behavior with weak ferromagnetic component to the magnetic interactions. [Copyright &y& Elsevier]

Uranium is one of the main crude materials for nuclear reaction, but the total uranium content on land is far from meeting the long-term needs of nuclear energy for the human being. How to enrich uranium from seawater with high reserves but extremely low uranium concentration and a great quantity of competitive ions has become a key project. In this work, we report the synthesis of aminooxime functionalized ZIF-90 by grafting 4-aminobenzamidoxime, named ZIF-90-ABOA , which exhibits outstanding adsorption performance benefitting from the high chelating ability of amidoxime towards uranium. The maximum adsorption capacity of uranium is 353.4 mg g−1 from aqueous solution, which is much higher than the original ZIF-90. Additionally, the adsorption capacity can reach 2.8 mg g−1 in 7 days from natural seawater, proving the potential enrichment of uranium in real application. Aminooxime functionalized ZIF-90 was successfully synthesized by covalent modification, which can efficiently extract uranium from natural seawater. [Display omitted] • ZIF-90 was functionalized by 4-aminobenzamidoxime groups via covalent modification. • Functionalized ZIF-90 shows superior adsorption performance compared with pristine one. • Functionalized ZIF-90 demonstrates a good prospect in real seawater application. [ABSTRACT FROM AUTHOR]

MOF-76 exhibits not only high sensitivity for the detection of U(vi), but also high adsorption capacity of 298 mg g−1 at a low pH value of ∼3.0. Furthermore, the high selectivity for uranium adsorption over a series of competing metal ions is also illustrated. [ABSTRACT FROM AUTHOR]

A series of novel ternary Ln–Ru–W hybrids constructed by metalloligands ([RuII(bpy)2(4,4′-dcbpy)](PF6)2, m-H2LRu) and high-nuclear lanthanide clusters have been successfully synthesized using an efficient “metalloligand” strategy for the first time. Slow magnetic relaxation has been observed within the Dy-based hybrid. [ABSTRACT FROM AUTHOR]

As an important metal element, aluminium has a significant impact on the environment and human health, and thus the detection of Al3+ has become the subject of much research. We synthesized a Ni(II)‐based metal–organic gel (Ni‐MOG), which can serve as an Al3+ fluorescence sensor with high selectivity and sensitivity, the limit of detection being calculated to be 0.5 μM. In addition, a composite film was further fabricated by hybridization of this Ni‐MOG with poly(vinyl alcohol). The composite film produced a rapid fluorescence response to Al3+ solutions at concentrations above 5 × 10−5 M in 5 min. The Ni‐MOG composite film can also be successfully applied for the sensitive detection of Al3+ in real samples of tap water and seawater. The effective detection of Al3+ described in this contribution provides a new insight into water quality monitoring and has promising application value. [ABSTRACT FROM AUTHOR]

Recently, highly porous metal–organic frameworks (MOFs), with excellent porosity and abundant functional groups, have represented a new addition to the area of capturing uranium ion pollutants. To achieve high adsorption capacity and removal efficiency of uranium, it is significant to modify the morphology of MOF-based adsorbents. In this contribution, two hollow structured ZIF-8 adsorbents were used for the adsorptive separation of uranium from aqueous solution. Both of them showed faster adsorption rate and larger adsorption capacity than pristine ZIF-8, providing the prospect of hollow MOF materials to the application of uranium extraction. [ABSTRACT FROM AUTHOR]

Owing to their highly predictable porous structures, facile synthesis, and the presence of functional open metal sites, metal–organic frameworks (MOFs) are extensively employed in various fields, including energy storage, catalysis, adsorption, and separation. Nevertheless, the limited hydrolytic stability exhibited by numerous MOFs poses a significant challenge to their practical application. In the present study, we present the synthesis and characterization of a uranyl organic framework (TCPP‐U1) with a highly porous structure, which is constructed by assembling cobalt, uranyl, and the porphyrin ligand 5,10,15,20‐tetra(4‐carboxyphenyl)porphyrin (TCPP). However, TCPP‐U1 demonstrates poor hydrolytic stability when exposed to water (the structure can be destroyed even after 2 min of exposure to water), greatly impeding its potential applications that would benefit from its high surface area. To address this limitation, we developed a hybrid composite by incorporating acid‐treated multi‐walled carbon nanotubes (CNTs) into the TCPP‐U1 framework via a solvothermal method designated as CNTs@TCPP‐U1. Remarkably, the obtained CNTs@TCPP‐U1 composite possesses an identical crystal structure and morphology to the original TCPP‐U1 yet exhibits significant enhancements in hydrolytic stability (the structure remains stable even after 3 days of immersion in water). Furthermore, CNTs@TCPP‐U1 demonstrates a significant photocatalytic effect on the degradation of tetracycline hydrochloride in aqueous solutions. The reaction rate constant (k) for the pseudo‐first‐order kinetic model is 0.0059 min−1. Our findings present a novel perspective for enhancing the stability and expanding the performance of MOFs materials. [ABSTRACT FROM AUTHOR]

Single‐atom catalysts are one of the most energetic frontier research fields of catalysis, which exhibit distinctive performance for diverse chemical reactions due to the unique coordination environment, high atomic utilization, high activity and selectivity. Nevertheless, the size decrease of catalyst particles is accompanied with the sharply increased surface energy, thus ultra‐small particles are easy to form aggregation of nanoclusters and cannot maintain the atomic level dispersion. The key factor to protect catalytic sites is to regulate and control the interaction between single atoms and the substrate. As one of the most promising two‐dimensional supports to stabilize the isolated metal atoms, graphitic carbon nitride has been widely studied owing to the existence of abundant pyridine‐like nitrogen atoms for strongly anchoring metal centers and the distinct structure originating from electron rearrangement caused by the interaction between carbon and neighbor nitrogen atoms. In this review, we systematically generalize the controllable syntheses, theoretical calculations, characterizations and applications of graphitic carbon nitride supported isolated single‐atom catalysts, and finally, the prospects and challenges in this emergent field are featured on the basis of current experimental and computational efforts. [ABSTRACT FROM AUTHOR]

An tetraphenylethylene-based MOF (HNU-49) has been synthesized, which exhibits interesting piezofluorochromic behavior. Additionally, rhodamine B (RhB) can be successful encapsulated in HNU-49, to emit the characteristic dual-emission of RhB and the framework. The combination of host–guest interaction and piezofluorochromism can precisely modulate the luminescence to achieve near white-light. [ABSTRACT FROM AUTHOR]

One of the challenges to sustainability is to efficiently and conveniently remove organic dyes from wastewater. Herein, a light ZIF-8@chitosan (CS) composite sponge with bulk density of 0.18 g cm−3 was prepared by an in situ method. The composite sponge possesses a three-dimensional porous structure with abundant chelating sites, which can efficiently and selectively remove congo red (CR). The maximum adsorption capacity (987.01 mg g−1) is higher than most chitosan-based adsorbents. High selective adsorption towards CR over other dyes is also demonstrated. Over 90% adsorption capacity was retained after five adsorption–desorption cycles. In addition, a column-mounted equipment for fixed-bed cycle wastewater treatment was assembled with a freestanding ZIF-8@CS sponge, which exhibited high CR removal efficiency of 99%. Based on the systematic spectroscopy characterization, the dominant role in the superior adsorption performance is attributed to the electrostatic interactions, hydrogen bonds, π–π stacking and metal coordinating interaction between the ZIF-8@CS sponge and CR. [ABSTRACT FROM AUTHOR]

A composite membrane was prepared by in‐situ synthesis of ZIF‐8 on cellulose matrix in alkali/urea system. SEM revealed that ZIF‐8 particles are uniformly dispersed and tightly wrapped around the regenerated cellulose membrane which features a three‐dimensional porous structure. XRD, XPS and IR demonstrated the successful synthesis of ZIF‐8 on cellulose. Dye filtration experiments revealed high rejection rate (96 %) and selectivity for rhodamine B. Moreover, the composite membrane exhibited good cycling behavior with the rejection rate staying over 84 % after five cycles. The finding in this work provides a strategy for the rational design and fabrication of composite materials of cellulose and MOFs with promising application for wastewater purification. [ABSTRACT FROM AUTHOR]

The capture and recycle uranium from wastewater is very important for the environmental protection and sustainable nuclear energy development. In this work, functionalized hollow mesoporous silica nanospheres bearing aminopropyl and Schiff base groups, abbreviated as HMSNs‐NH2 and HMSNs‐SA, respectively, were prepared for the removal of U(VI) from aqueous solution. The effects of solution pH, adsorption kinetics, thermodynamics and isotherms, as well as the presence of competing metal ions on the uranium adsorption onto the two adsorbents were investigated in detail. It was found that both adsorbents showed largely enhanced adsorption capacity and good selectivity towards U(VI) than unfunctionalized HMSNs. The maximum adsorption capacities reach 499.72 mg/g for HMSNs‐NH2 and 317.29 mg/g for HMSNs‐SA, which are at a high level compared with the reported functionalized mesoporous silica materials. Furthermore, both adsorbents can rapidly remove uranium with the removal rate more than 97% from tap water and 85% from seawater with injected uranium of 5 ppm. The findings of the present work provide new actinide adsorbents by combining organic ligands with hollow mesoporous matrixes. [ABSTRACT FROM AUTHOR]

Highlights • A ZnO@ZIF-8 core-shell microsphere material was synthesized by the self-template method. • The core-shell microspheres exhibit much higher response, selectivity and stability than pure pristine ZnO towards ethanol than other VOCs. • This material is a promising gas sensor for ethanol detection. Abstract The ZnO@ZIF-8 (ZIF-8 = zeolite imidazolate framework-8) core-shell material was synthesized by the self-template method. The positive effects of the structure and morphology of ZIF-8 pre-concentrator on the sensing property of ZnO microsphere were investigated by FTIR, XRD, SEM and TEM characterizations, as well as gas detection measurement. The synthesized ZnO@ZIF-8 core-shell material exhibited much higher sensor response (35.90), selectivity and stability compared with pure hollow ZnO microsphere (14.54) at an optimal temperature of 160°C when exposed to ethanol than other volatile organic compounds (VOCs). The obtained results suggested that ZnO@ZIF-8 core-shell material is efficient in sensing ethanol than pristine ZnO microsphere, showing potential application as a selective ethanol detector. [ABSTRACT FROM AUTHOR]

Review: 78 refs. [ABSTRACT FROM AUTHOR]

Due to low cost and abundance, direct seawater splitting to produce hydrogen is an encouraging strategy to alleviate the consumption of fossil energy, while also avoiding freshwater stress. However, when natural seawater is utilized as the electrolyte, the catalysts on the cathode and anode of water splitting should not only have high activity to promote energy efficiency, but also have good stability and durability to resist the corrosion of chloride ions. Herein, a hierarchical carbon-based catalyst for hydrogen and oxygen evolution, ZIF-67/CF-1, was prepared by annealing a composite of ZIF-67 and carbon fiber (CF). It exhibits good electrocatalytic activity and stability for overall splitting in natural seawater and neutral PBS solution. Impressively, when an electrolyzer consisting of ZIF-67/CF-1||ZIF-67/CF-1 is applied to overall seawater splitting, the current density of 10 mA/cm2 is achieved with a drive voltage of 2.46 V, which is only 0.28 V higher than precious metal-based electrolyzer (Pt/C||IrO 2). Meanwhile, ZIF-67/CF-1 shows outstanding catalytic ability for oxygen reduction (E 1/2 = 0.84 V, Tafel slope = 66.9 mV/dec), also demonstrating its application potential in rechargeable batteries and fuel cells. A hierarchical carbon-based electrocatalyst (ZIF-67/CF-1) were developed for oxygen evolution on the anode and hydrogen evolution/oxygen reduction on the cathode. It owns good activity, stability and durability for hydrogen and oxygen evolution in natural seawater, and has been used as a bifunctional catalyst for overall seawater splitting in a two-electrode electrolyzer. Additionally, ZIF-67/CF-1 exhibits the high half-wave potential and small Tafel slope value for oxygen reduction in 0.1 M KOH. [Display omitted] • The hierarchical carbon-based catalysts for HER, OER and ORR were prepared. • ZIF-67/CF-1 exhibits good electrocatalytic ability for overall seawater splitting. • The current density of 10 mA/cm2 is achieved with a cell voltage of only 2.46 V. • The ORR catalytic performance of ZIF-67/CF-1 is comparable to that of Pt/C. • N-doped hierarchical carbon is beneficial to the electrocatalytic performance. [ABSTRACT FROM AUTHOR]

[Display omitted] Photocatalytic decomposition of water for hydrogen production using semiconductor photocatalysts in visible light is considered one of the most promising environmentally friendly ways to produce hydrogen. In this work, the calcination method was adopted to prepare an efficient Cu 3 P/WSe 2 /CNTs composite photocatalysts. Cu 3 P and carbon nanotubes (CNTs) were used as co-catalysts to reduce the composite rate of the photogenerated supports of the photocatalyst. The unique metallic properties of Cu 3 P as a transition metal phosphide makes it a cost-effective alternative to noble metal co-catalysts. CNTs can serve both as co-catalysts and as a suitable carrier to accelerate the transfer rate of photogenerated electrons. The experimental results showed that the Cu 3 P/WSe 2 /CNTs composite photocatalyst exhibited stronger activities in photocatalytic hydrogen production than pure WSe 2. In particular, a higher quantum yield of 30.27% at the range 400–700 nm was achieved with a loading of 4% CNTs, a calcination temperature of 300 °C and a calcination time of 2.0 h. In contrast, the quantum yield of pure WSe 2 was only 14.01%. The highest hydrogen production rate was 6.987 mL in 4.0 h, and the average hydrogen production rate was 712.985 μmol·h-1g−1, which was 2.39 times higher than that of pure WSe 2.The catalytic memory performance of the composite samples was also examined. The results indicated that the best catalytic memory performance was achieved under the pre-illumination condition of 5.0 h. The amount of hydrogen produced under darkness for 4.0 h was up to 4.934 mL and the average hydrogen production rate was 503.454 μmol·h-1g−1. The average hydrogen production rate was 1.69 times higher than the average hydrogen production rate of pure WSe 2 under light conditions. [ABSTRACT FROM AUTHOR]

Space-confined growth of nanoscale MOFs in hollow mesoporous silica nanospheres was achieved by a general "stepwise vacuum evaporation" strategy, the Pd functionalized of which showed excellent activity in the catalytic reduction of 4-nitrophenol. [Display omitted] • Space-confined growth of nanoscale MOFs in hollow mesoporous silica was achieved. • A general "stepwise vacuum evaporation" strategy is proposed. • UiO-66-NH 2 @HMSN can further modify Pd to form functionalized materials. • UiO-66-NH 2 /Pd@HMSN exhibits excellent activity in the catalytic reduction of 4-nitrophenol. The development of confined growth of metal-organic frameworks (MOFs) in a nano-space remains a challenge mainly due to the spatial size randomness and inhomogeneity of host materials and the limitation of MOF species. In this study, we developed a general "stepwise vacuum evaporation" strategy, which allows the nano-confined growth of MOFs in hollow mesoporous silica nanospheres (HMSN) by the vacuum forces and the capillary effect. A series of nanoscale MOFs including ZIF-8, ZIF-90, HKUST-1, MIL-53(Cr) and UiO-66-NH 2 were confinely synthesized inside the cavities of HMSN, resulting in hierarchically porous composites with core-shell structures. Further functionalization was studied by anchoring Pd to obtain UiO-66-NH 2 /Pd@HMSN catalyst, which exhibited excellent activity in the catalytic reduction of 4-nitrophenol to 4-aminophenol under ambient condition. [ABSTRACT FROM AUTHOR]

[Display omitted] • The CNQDs/CN/CNTs photocatalyst was obtained by a microwave hydrothermal method. • The CNQDs/CN/CNTs has higher separation efficiency of photogenerated carriers. • CNQDs and CNTs together enhanced the photocatalytic performance of g-C 3 N 4. • The CNQDs/CN/CNTs generated 1109.388 μmol∙g−1∙h−1 hydrogen with QY of 52.08%. Utilizing solar energy to facilitate photocatalytic hydrogen production holds great promise in addressing the energy crisis. One material that shows tremendous potential in this field is two-dimensional graphitic carbon nitride (2D g-C 3 N 4). However, the fast recombination rate of photogenerated carriers and the limited specific surface area impede its photocatalytic activity. This research endeavors to address these limitations by developing a ternary composite photocatalyst, CNQDs/g-C 3 N 4 /CNTs, by employing the microwave hydrothermal method. g-C 3 N 4 was co-modified with zero-dimensional g-C 3 N 4 quantum dots (0D CNQDs) and one-dimensional carbon nanotubes (1D CNTs). Incorporating CNQDs and the g-C 3 N 4 interface facilitates the separation of photogenerated carriers, while the tubular channel of CNTs provides favorable conditions for transferring photogenerated electrons. Additionally, the introduction of CNQDs and CNTs significantly increases the specific surface area of the sample, thereby enhancing the number of reaction active sites available for the photocatalytic production of hydrogen. The hydrogen generation rate of the CNQDs/g-C 3 N 4 /CNTs is 1109.388 μmol⋅g−1⋅h−1, surpassing that of the single g-C 3 N 4 specimen by 3.62 times. The application of density functional theory (DFT) calculations reinforces the enhanced performance of the composite through the synergistic effect of CNQDs and CNTs. This effect optimizes the adsorption behavior of the active intermediate (H*) and reduces the Gibbs free energy ΔG(H*) associated with the photocatalytic hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

• The photothermal film with Janus structure was prepared by one step method. • The photothermal film can realize self-floating and avoid salt accumulation. • Polydopamine has excellent adhesion and stability to mixed cellulose membrane. A variety of photothermal materials have been developed and applied in photothermal seawater desalination. As a conjugated polymer, Polydopamine (PDA) has excellent light absorption properties in the UV–visible region, and is widely used as a solar energy material. In this work, Polydopamine-mixed cellulose membrane (PDA@MCE) with Janus structure was prepared by a one-step method for water evaporation at the interface between PDA and mixed cellulose membrane (MCE). PDA@MCE has good thermal stability. When the reaction time is 6 h, the evaporation rate of the composite is twice that of MCE, and the photothermal conversion efficiency is about 62 %. PDA@MCE, as a kind of photothermal material with simple preparation method and friendly to the environment, has excellent application potential in solar driven interfacial water evaporation. [ABSTRACT FROM AUTHOR]

Utilizing in-situ hydrothermal synthesis, the integration of MIL-88A with self-made PVA sponge was achieved, forming MIL-88A/PVA composite, which demonstrates effective performance in degrading tetracycline antibiotics during water treatment. [Display omitted] • The MIL-88A/PVA sponge composite achieves a high removal rate within 4 min. • MIL-88A/PVA treats 2160 L wastewater in 24 h in fixed-bed column experiments. • The composite's bulk morphology is customized to meet specific industrial requirements. • This approach expands the application of MOF materials in antibiotic wastewater treatment through sulfate radical-advanced oxidation processes. MIL-88A is a metal–organic framework (MOF) material known for its excellent performance in advanced oxidation processes (AOPs). However, due to its powdery nature, MIL-88A may undergo loss during catalytic degradation in flowing solutions, making continuous degradation removal challenging. Herein, we report the synthesis of MIL-88A/PVA sponge composite material by the in-situ integration of MIL-88A with PVA sponge. The composite sponge exhibits excellent removal efficiency of tetracycline antibiotics under the conditions of sulfate radical-advanced oxidation processes (SR-AOPs), achieving a degradation rate exceeding 99.0% within 2 min. Additionally, through fixed-bed column experiments, 1 kg of MIL-88A/PVA can treat 2160 L of wastewater within 24 h, indicating promising industrial applicability. It's worth noting that this material can be customized into any desired block shape as needed. This work offers a highly promising solution for the application of MOF-based bulk-type catalysts in the treatment of antibiotic pollution using SR-AOPs. [ABSTRACT FROM AUTHOR]

Green hydrogen is widely recognized as one of the most promising new renewable energy sources that can replace traditional fossil fuels. At the same time, the photocatalytic decomposition of water to produce hydrogen is also considered a renewable and sustainable process of converting solar energy into chemical energy. Herein, in this paper, a high-performance MoP/SiC composite photocatalyst was synthesized by a facile low-temperature hydrothermal method. Notably, we used a solid-state low-temperature phosphating method to prepare MoP with amorphous properties and quantum dot size (2–3 nm) as a photocatalytic hydrogen production co-catalyst, which affords an effective way of alternating precious metal co-catalysts. The results of H 2 production studies display that amorphous MoP quantum dots can dramatically strengthen the photocatalytic hydrogen production performance of SiC. Especially, as the loading of MoP is up to 2.5%, it has the optimal hydrogen production performance, the hydrogen production rate is so high that it reaches 589.23 μmol h−1 g−1 with a quantum yield (QY 400–700 nm) 27.66%, which is 25 folds compared with that of pure SiC. The brilliant co-catalytic behaviour of the amorphous MoP quantum dots is ascribed to their unique amorphous structure and ultra-small particle size, which substantially enhances the photogenerated charge separation efficiency of the main catalyst SiC, as well as reveals plenty of hydrogen-producing active sites, which further facilitates the reaction over the catalyst surface. This work unlocks a new and unprecedented strategy for SiC-based composite photocatalysts in the field of photocatalysis. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • An efficient turn-on fluorescent sensor is constructed from copper-functionalized zinc-based CP. • Cu@Zn-CP exhibits ultrafast response and trace detection ability towards thiol compounds. • The sensor displays general ability towards thiol compounds. • The sensor demonstrates excellent sensing and recovery capability for thiol compounds in real water samples. As a kind of commonly-used synthetic materials for many pesticides, thiol compounds, once being leaked, can cause serious harm to the environment and humans. Therefore, the efficient detection of thiol compounds is essential. In this study developed a turn-on fluorescent probe (Cu@Zn-CP) for the highly sensitive fluorescence detection of thiol compounds. The probe was constructed based on a zinc coordination polymer (Zn-CP), whose fluorescence was quenched through the effective doping of Cu2+ ions. After the introduction of methyl thioglycolate (MTC), a rapid fluorescence turn-on response was generated within 90 s with a low detection limit of 23 ppb. Even after being reused for five cycles, the sensor maintains excellent detection performance and demonstrates good recyclability. It can also detect MTC in river water, with a spike recovery rate between 98–103 %. Furthermore, the designed Cu@Zn-CP exhibits good universality for detecting multifarious thiol compounds, including L-cysteine, glutathione, monothioglycerol, and 2-hydroxy-1-ethanethiol. This result provides a potential recyclable fluorescent sensor for thiol compounds. [ABSTRACT FROM AUTHOR]

The photocatalytic reduction of uranium from nuclear wastewater represents a promising method for both uranium extraction and environmental remediation. This approach facilitates the recovery of uranium resources for the nuclear industry while addressing environmental pollution. Despite significant research advancements, there remains a need for cost-effective and environmentally friendly catalytic materials. In this context, we present a two non-metal O, P co-doped g-C 3 N 4 (OPCN) synthesized via a simple one-step thermo-polymerization in air. OPCN demonstrates a high uranium reduction efficiency of 94.9 % under white LED light illumination. Even after five cycles, OPCN maintained a reduction efficiency of 81.7 %, highlighting its stability and reusability. Additionally, OPCN also performs effectively in uranium reduction under natural sunlight and exhibits impressive antimicrobial properties. These features position OPCN as a promising candidate for practical environmental applications. O, P-doped g-C 3 N 4 (OPCN) was synthesized by one-step thermal polymerization in the air. The hexavalent uranium was effectively reduced to tetravalent uranium under white LED irradiation. And it has good stability and reusability. Additionally, OPCN showed excellent catalytic performance for uranium reduction under natural sunlight and exhibited notable antimicrobial properties, making it a potential candidate for practical environmental applications. [Display omitted] • One kind of two non-metal O, P co-doped g-C 3 N 4 (OPCN) is easily synthesized by one-step thermo-polymerization in the air. • OPCN shows a high uranium-reduction efficiency of 94.9 % under white LED light illumination. • After five cycle experiments, the favorable reduction ability (81.7 %) is till obtained, demonstrating the favorable stability and reusability of OPCN. • The good catalytic result of uranium reduction under real sunlight and its fine antimicrobial properties makes OPCN a potential photocatalytic material applied in practical environments. [ABSTRACT FROM AUTHOR]

The luminescent properties of a family of lanthanide metal-organic frameworks LnL ( Ln=Y, La-Yb, except Pm; L=4,4′-({2-[(4-carboxyphenoxy)methyl]-2-methylpropane-1,3-diyl}bis{oxy})dibenzoic acid) have been explored, and the energy-transfer process in the compounds has been carefully analyzed. The visible-emitting Tb0.08Gd0.92L and the near-infrared (NIR)-luminescent Yb0.10Gd0.90L show excellent optical performances and can be considered as fluorescent probes for acetone sensing based on luminescence quenching effects arising from host-guest interactions. Moreover, GdL exhibits a strong second harmonic generation (SHG) signal 6.1 times that of potassium dihydrogen phosphate (KDP) and an outstanding phase-matchable effect. These lanthanide compounds combining fluorescent and nonlinear optical (NLO) properties could meet further requirements as multifunctional materials. [ABSTRACT FROM AUTHOR]

Solvothermal reactions of hexa[4-(carboxyphenyl)oxamethyl]-3-oxapentane (H6L) with rigid coligands, 2,2′-bipyridine (bipy), 1,4-bis-(1-imidazolyl)benzene (dib), and 4,4′-bis(1-imidazolyl)biphenyl (bibp) in the presence of manganese salts produce four porous Mn(ii) metal–organic frameworks (Mn–MOFs), namely, Mn3(L)(bipy)2 (1), Mn3(L)(dib) (2), Mn3(L)(dib)(H2O)2 (3), and Mn6(L)2(bibp)1.5(H2O)54. Single crystal X-ray diffraction analyses reveal that 1–4 consist of trinuclear MnII subunits, which are further connected into four interesting nets, 4,4-connected pts net for 1, 4,6-connected fsc net for 2, and two novel nets for 3 and 4, by the synergistic effect of carboxylate groups and functionally complementary N-donor ligands. They exhibit high potential solvent accessible volumes of 35.0%, 33.5%, 45.1%, and 56.5% for 1–4, respectively. Magnetic studies indicate the presence of weak antiferromagnetic interactions between MnII centers in these compounds. [ABSTRACT FROM AUTHOR]

[Display omitted] • • The melamine sponge@covalent organic framework composite (MS@TpTt) was prepared. • • MS@TpTt prepared via a one-pot method by "reactive seeding" strategy. • • MS@TpTt has better photocatalytic activity for tetracycline degradation than TpTt. • • MS@TpTt shows excellent recyclabilit, which can be recycled more than 10 times. Covalent organic frameworks (COFs), have been used as potential photocatalysts for the degradation of antibiotics, but their poor recyclability limits the application in practical environment. In this paper, a novel melamine sponge@COF composite sponge was successfully prepared via a one-pot method by "reactive seeding" strategy. Such strategy enables the uniform and sturdy growth of small-sized COF-TpTt on the melamine sponge (MS) fibers. The composite sponge (MS@TpTt) effectively overcomes the difficulty of recycling for the powder character of general COFs, and shows excellent photocatalytic activity towards the degradation of tetracycline antibiotics under visible light. The finding in this work provides a simple strategy for the preparation of COF-based composite monolithic materials with high degradation performance, easy circulation and high stability for desired catalytic applications. [ABSTRACT FROM AUTHOR]

In this work, a non-steady electrochemical model for assessing stress corrosion cracking (SCC) of 2205 duplex stainless steel (DSS) under applied polarization potentials was proposed, and the SCC mechanism was revealed. With the negative shift of potentials, hydrogen enhances SCC susceptibility by deteriorating passive film, inhibiting repassivation and causing serious damage. In particular, at −850 mV (vs. SCE), the synergetic effect of anodic dissolution (AD) and hydrogen embrittlement (HE) causes severe pitting and SCC. The negative shift of applied potentials changes the preferential pit/SCC initiation site due to high hydrogen concentration in austenite. • A non-steady electrochemical model for assessing SCC of 2205 duplex stainless steel was proposed. • The direct evidence was provided that the synergy of anodic dissolution and hydrogen embrittlement controls SCC. • The negative shift of potentials varies the initiation sites of pits and SCC because of hydrogen enrichment in austenite. [ABSTRACT FROM AUTHOR]

Parkinson's disease (PD) is a progressive age-related movement disorder caused by dopaminergic neuron loss in the substantia nigra. Diffusion-based magnetic resonance imaging (MRI) studies—namely, diffusion tensor imaging (DTI)—have been performed in the context of PD, either with or without the involvement of sleep disorders (SDs), to deepen our understanding of cerebral microstructural alterations. Analyzing the clinical characteristics and neuroimaging features of SDs in early PD patients is beneficial for early diagnosis and timely invention. In our present study, we enrolled 36 early PD patients (31 patients with SDs and 5 patients without) and 22 healthy controls. Different types of SDs were assessed using the Rapid Eye Movement Sleep Behavior Disorder Questionnaire—Hong Kong, Epworth Sleepiness Scale, International Restless Legs Scale and PD Sleep Scale-2. Brain MRI examinations were carried out in all the participants, and a region-of-interest (ROI) analysis was used to determine the DTI-based fractional anisotropy (FA) values in the substantia nigra (SN), thalamus (Thal) and hypothalamus (HT). The results illustrate that SDs showed a higher prevalence in the early PD patients than in the healthy controls (86.11% vs. 27.27%). Early PD patients with nighttime problems (NPs) had longer courses of PD than those without (5.097 ± 2.925 vs. 2.200 ± 1.095; p < 0.05), and these patients with excessive daytime sleepiness (EDS) or restless legs syndrome (RLS) had more advanced Hoehn and Yahr stages (HY stage) than those without (1.522 ± 0.511 and 1.526 ± 0.513, respectively; both p < 0.05). Compared with the early PD patients without probable rapid eye movement sleep behavior disorder (pRBD), those with pRBD had longer courses, more advanced HY stages and worse motor and non-motor symptoms of PD (course(years), 3.385 ± 1.895 vs. 5.435 ± 3.160; HY stages, 1.462 ± 0.477 vs. 1.848 ± 0.553; UPDRS, 13.538 ± 7.333 vs. 21.783 ± 10.766; UPDRS, 6.538 ± 1.898 vs. 7.957 ± 2.345; all p < 0.05). In addition, the different number of SD types in early PD patients was significantly inversely associated with the severity of damage in the SN and HT. All of the early PD patients with various SDs had injuries in the SN, in whom the damage was more pronounced in patients with NP than those without. Moreover, early PD patients with NP, RLS or pRBD had worse degrees of HT damage than those without. The current study demonstrated the pathophysiological features and neuroimaging changes in early PD patients with various types of sleep disorders, which will help in early diagnosis and therapy. [ABSTRACT FROM AUTHOR]

Abstract: Erbium oxide has been successfully incorporated into SBA-15 and different types MCM-41 mesoporous materials via thermal diffusion methods. A series of characterizations were used to characterize the prepared materials. In the prepared host–guest materials, the frameworks of the host materials were kept intact, and the guest erbium oxide mainly located inside the pores of the host materials. The host–guest composite materials showed the luminescent properties, and the luminescent intensities were excellent. Luminescence studies also revealed that the different particle size of the host materials have biggish influence to the luminescence characters. Moreover, the luminescence intensity and luminescence lifetime could be increased by the modification of the mesoporous materials surface. The better luminescent performances made these prepared materials show potential applications in optical amplification, laser systems, or medical diagnostics. [Copyright &y& Elsevier]

Electrochemical water splitting, metal-air batteries and fuel cells are the representatives of energy storage/conversion technology, which can solve the shortage of traditional fossil energy and environmental issues. However, under neutral conditions, especially in natural seawater, there is still a lack of catalysts with efficient catalytic activity and stability, which hinders the development of hydrogen production. We herein designed a facile strategy to fabricate an efficient and stable multifunctional carbon-based electrocatalyst, PMA@ZIF-67-C-AT, by carbonization and acid treatment of H 3 PMo 12 O 40 @ZIF-67 precursor. It not only performs good catalytic activity for oxygen evolution in 0.2 M phosphate buffer solution (PBS) and actual seawater, but also exhibits hydrogen evolution overpotential of 650 mV (j = 3 mA/cm2) in PBS and even as low as 570 mV (j = 10 mA/cm2) in seawater. Besides, it also displays excellent catalytic performance for oxygen reduction (E 1/2 at 0.83 V and the Tafel slope of 63 mV/dec). By investigating the composition and morphology of the materials, it was found that acid treatment changed the active components and carbon matrix of the catalysts, thus affecting the catalytic performance. A multifunctional carbon-based electrocatalyst, PMA@ZIF-67-C-AT, was successfully prepared by carbonization and acid treatment of H 3 PMo 12 O 40 @ZIF-67 precursor. It not only exhibits excellent catalytic performance for ORR in alkaline solution, but also has efficient catalytic activity and stability for HER and OER actual seawater. [Display omitted] • Multifunctional carbon-based catalyst derived from polyoxometalates and MOFs. • Efficient bifunctional catalyst for hydrogen and oxygen evolution in seawater. • Excellent ORR catalytic ability with a Tafel slope smaller than that of Pt/C. • The performance of catalyst is affected by active components and carbon matrix. [ABSTRACT FROM AUTHOR]

It is of great significance to develop efficient platforms for the detection of hypertoxic Hg2+. Colorimetric probes have received much attention for the detection of Hg2+ in the last decades. In this work, a colorimetric probe composed of MnO2 nanosheets and monothioglycerol (MTG) was rationally designed for Hg2+ detection, which was facially prepared via one‐step reaction at room temperature. The formation of Hg−S bond between Hg2+ and MTG inhibited the decomposition ability of MTG toward MnO2 nanosheets, thus resulting in a color change from colorless to brown. On this basis, the probe quantified Hg2+ in the concentration range from 2 to 60 μM with a low detection limit of 0.75 μM. The probe was applied to the detection of Hg2+ in tap water successfully, and was further fabricated into test strips for the convenience of use. Thereby, a simple and sensitive colorimetric probe for Hg2+ is developed in this work, which holds future promise for monitoring Hg2+ in the environment. [ABSTRACT FROM AUTHOR]

Green and clean energy technologies, including fuel cells, metal-air batteries, water splitting et al., are becoming more significant for our lives. Oxygen reduction reaction (ORR), hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) are key reaction processes for fuel cells, metal-air batteries and water splitting. Therefore, it is highly desirable to design a multifunctional catalyst, which owns catalytic performance under a widely applied range. Herein, we demonstrate a novel multifunctional catalyst (Co/Co 3 O 4 @C) by carbonizing a composite material constructed of zeolite imidazolate framework and carbon fiber paper (ZIF-L-Co@CP). It is a carbon-based material containing metallic Co and Co 3 O 4 as a low-cost and effective catalyst toward the ORR and overall water splitting. For ORR, the Co/Co 3 O 4 @C catalyst shows high half-wave potential in both alkaline and acidic media, 0.823 V for 0.1 M KOH and 0.672 V for 0.1 M HClO 4. More importantly, it exhibits good catalytic activities of hydrogen and oxygen evolutions to perform overall splitting in actual seawater. The Co/Co 3 O 4 @C catalyst was prepared by using a composite of ZIF-L-Co nanosheets grown on CP as the precursor, which not only shows excellent activity for ORR in both alkaline and acidic solutions, but also has good ability for overall actual seawater splitting. Image 1 • E 1/2 (0.823 V) of Co/Co 3 O 4 @C catalyst is close to Pt/C in 0.1 M KOH for ORR. • Co/Co 3 O 4 @C catalyst shows excellent ORR performance in 0.1 M KOH and 0.1 M HClO 4. • Co/Co 3 O 4 @C is a good catalyst for overall water splitting in actual seawater. [ABSTRACT FROM AUTHOR]