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Reconstruction of sedimentary evolution plays a significant role in the investigation of natural groundwater contamination and stratigraphic mineral resources. In this paper, the variation in sedimentary characteristics and sedimentary evolution were studied by lithology, chronology and organic matter with the high-resolution grain size parameters of boreholes for Quaternary in northern Jianghan Basin. Following more traditional plotting of grain size parameters and summary statistics, visual categorization and analysis of grain size frequency distribution curves provided an effective measure for the identification of sedimentary facies. Combining with the Fisher model, new and highly efficient discriminant formulas were established, and tested for the validity. Additionally, the sedimentary evolution process and the provenance of different sedimentary facies were identified with the help of organic matter and δ13Corg data, provided geological information to explore the natural contamination of reducing arsenic ions and excessive nitrate in strata. The identification results suggest that fluvial and lacustrine sediments are dominant in the area, and the regional sedimentary environment is uniform and not affected by the transgression. The analysis results of grain size with organic matter parameters are consistent for discriminating sedimentary facies, which verified the rationality of grain size analysis and confirmed the use of organic matter content to be effective in identifying the process of fluvial and lacustrine sediments. Based on the chronological results of Optically Stimulated Luminescence dating and sedimentary facies determination, the sedimentary evolutionary process was deduced during the Quaternary for the study area. This research has important significance for the division and correlation of Quaternary borehole strata, underground contamination study, as well as environmental planning and protection.

This paper studies a dissipative heat equation with Delta sources of non-linear strength located on a periodic lattice. The model arises from intracellular waves in continuum excitable media with discrete release sites. Due to the presence of Delta sources, the solution of the model has discontinuous spatial derivatives. We focus on the bistable regime of the model, determined by the decay strength parameter a and the separation distance L between release sites, in which the model admits exactly three L-periodic steady states. We establish the existence of pulsating waves spatially connecting them. For the case of waves connecting two stable L-periodic steady states, the uniqueness and global exponential stability of pulsating waves are shown. Also a new technique is introduced to find the fine structure of the tails of pulsating waves.

Although using elemental powder mixtures may provide broad alloy selection at low cost for selective laser melting (SLM), there is still a concern on the resultant microstructural and chemical homogeneity of the produced parts. Hence, this work investigates the microstructure and mechanical properties of a SLM-produced Ti-35Nb composite (in wt%) using elemental powder. The microstructural characteristics including β phase, undissolved Nb particles and chemical homogeneity were detailed investigated. Nanoindentation revealed the presence of relatively soft undissolved Nb particles and weak interface bonding around Nb-rich regions in as-SLMed samples. Solid-solution treatment can not only improve chemical homogeneity but also enhance bonding through grain boundary strengthening, resulting in ∼43 % increase in tensile elongation for the heat-treated Ti-35Nb compared to the as-SLMed counterpart. The analyses of tensile fractures and shear bands further confirmed the correlation between the different phases and the ductility of Ti-35Nb. In particular, the weak bonding between undissolved Nb and the matrix in the as-SLMed sample reduces its ductility while the β grains in solid-solution treated Ti-Nb alloy can induce a relatively stable plastic flow therefore better ductility. This work sheds insight into the understanding of homogenization of microstructure and phases of SLM-produced alloys from an elemental powder mixture.

Ionic liquids (ILs) play an important role in conducting polymer poly(3,4-ethylenedioxythiophene) (PEDOT) based electronics and thermoelectrics through regulating morphology and electronic properties. Herein, the hole transport and interface electronic coupling properties of three kinds of IL ([BMIM]:[BF4], [BuPhIM]:[BF4], and [BnPhIM]:[BF4]) mediated PEDOT systems have been researched via multiscale molecular mechanics simulations and quantum mechanics calculations, where the cations of the ILs feature gradually extended π-conjugation. It is indicated that [BnPhIM]:[BF4] induces PEDOT to show more ordered π–π stacking than its counterparts, where the chains are oriented with face-to-face alignment. This is attributed to the larger evenness of the net charge distribution at the [BnPhIM]:[BF4]-PEDOT interface. Consequently, the average mobility in [BnPhIM]:[BF4]-PEDOT is 4.01 cm2 V−1 s−1 and the instantaneous maximum reaches 17 cm2 V−1 s−1, far surpassing its counterparts. Although the predicted PEDOT single crystal presents a well-ordered lamellar structure, the one-dimensional orientation causes hole tunneling along the nanowire-like direction, leading to its mobility lagging behind the [BnPhIM]:[BF4] decorated system by one order of magnitude. On the other hand, the interface electronic coupling and doping efficiency in [BnPhIM]:[BF4]-PEDOT is strengthened, confirming that improving the π-conjugation of the cation of the IL can enhance the mobility of PEDOT and interface electronic coupling synergistically. To improve the mobility further, a novel series of cations containing [BnPhIM-oOMe]+, [BnPhIM-mOMe]+, and [BnPhIM-pOMe]+ has been designed based on the outstanding properties of [BnPhIM]+. Combining the novel designed cations with [BF4]− and [B(CN)4]−, it is observed that [BnPhIM-pOMe]:[B(CN)4] causes PEDOT to assemble with well-ordered π–π stacking. Assessments rationalize that it could serve as a potential candidate for application in PEDOT-based electronics, since it shows similar interface electronic coupling and has a 35–43% improvement in PEDOT mobility compared to the excellent reference [BnPhIM]:[BF4].

Rigid electron donors (D) and acceptors (A) have been widely used in recent years for the construction of D–A type thermally activated delayed fluorescence (TADF) materials. However, the chromophore robustness does not always make a positive contribution to the high efficiency of TADF materials. Here, the comparison study of two D–A type red TADF compounds (PT-TPA and PT-Az) demonstrated, for the first time, the positive impact of chromophore flexibility on the efficiency of TADF materials. In PT-Az, the rotation of terminal phenyl groups is restrained by an ethylene linker, leading to its inferior photoluminescence quantum yield (PLQY). In contrast, PT-TPA with free rotation of the phenyl groups showed a low reorganization energy and a large transition dipole moment for the S1 → S0 transition, which resulted in a high fluorescence radiative decay rate. As a result, the optimized devices based on PT-TPA gave a maximum external quantum efficiency (EQE) of 29.7% (632 nm) when doped in a single host and an EQE of 28.8% (648 nm) in an exciplex host. This study provided an insight into the impact of chromophore flexibility on the photophysical properties and device efficiency of TADF materials, and these results may provide valuable guidance for the molecular design of efficient emitters.

Due to the great limitation of glass forming ability, precisely controlling the chemical compositions of metallic glasses (MGs) still dramatically inhibits their widespread applications in wastewater remediation. Here, heterostructured catalysts were exploited by rapid annealing of Fe-based MGs and subsequent ball milling (BM) as advanced alternatives for amorphous counterparts in Fenton-like process. It was found that the surface characteristics tailored by ball milling enable more chemically active sites due to its enlarged specific surface area, surface defects and nanosized amorphous oxide layer that significantly enhance surface-catalyzed reaction in Fenton-like process. On the other hand, high-temperature annealing induced grain growth and electrochemical potential difference induced effect of galvanic cells in multiple crystalline phases (e.g. α-Fe (Si), Fe2B and Fe3Si) further provide an important contribution to high efficiency of electron transfer in heterostructured catalysts. Since the multiphase heterostructure is easily formed by a high-temperature annealing of MGs/amorphous-crystalline composite alloys, this work aims to provide an advanced alternative of MG catalyst without the elemental limitation of glass forming ability for wastewater remediation.

In this paper, shale gas cores from the Lower Silurian Longmaxi Formation in the Zhaotong National Shale Gas Demonstration Area were selected to study the hydration effect of different fluids on the fracture morphology inside the shale, the rock tensile strength and the Brazilian tensile failure mode. Fresh water and slick water were adopted for hydration pretreatments and the CT technique was used to compare the changes of the fabric in the shale. Then, Brazilian tensile tests were carried out to study the tensile strength and tensile failure modes of the shale specimen after hydration pretreatment. Finally, two horizontal wells in the study area were selected to perform pilot tests of hydration pretreatment in their fracturing operation sites. And the following research results were obtained. First, in the process of spontaneous imbibition, the hydration effect of fresh water is superior to that of slick water in promoting the fracture complexity of marine shale in the same hydration duration. Second, fresh water has greater surface tension and lower viscosity and its hydration effect can not only promote the propagation of original fractures but induce new micro-fractures or branches, while the hydration effect of slick water mainly promotes the propagation of original fractures. Third, due to hydration effect, marine shale is damaged and its tensile strength is reduced. After the hydration pretreatment by fresh water and slick water, the tensile strength of the shale specimens are reduced by 35.6% and 18.1%, respectively. Fourth, according to the propagation paths of main fractures, the Brazilian tensile failure modes of hydrated shale can be divided into four types (i.e., step shaped, dog-leg shaped, branching shaped and arc shaped) or their combinations, while the tensile failure mode of unhydrated shale is only a straight line. Fifth, hydration effect can effectively increase the complexity of the hydraulic fractures in marine shale, so if the conditions permit, it is recommended to inject a certain amount of fresh water at a high pumping rate within the limited pressure after perforation and to shut in the well until the hydraulic fracturing operation. And in order to reduce the difficulties of pumping the proppant during the hydraulic fracturing operation, a pumping strategy of “low proppant concentration, large volume of slurries” can be adopted to reach the expected proppant volume.

The shuttling of soluble lithium polysulfides (LiPSs) intermediates bottlenecks practical uses of lithium-sulfur (Li-S) batteries. A commercial organometallic salt, nickel chloride dimethoxyethane adduct (NiDME), is introduced as the homogenous catalyst dissolved in the electrolyte to suppress the shuttle effect. A very small amount of catalyst (only 0.5 wt% additive relative to the electrolyte) brings the battery capacity a big rise from 408 to 784 mAh g−1 over 500 cycles at 1 C. More promisingly, the required amount of electrolyte is greatly reduced, and the battery works well with a lean electrolyte (5 μL(electrolyte)/mg(sulfur)). The improved performance is attributed to the catalyst-accelerated LiPS conversion which is characterized by largely decreased activation energy (Ea) of the sulfur redox reaction, especially for Li2S deposition, and much reduced accumulation of LiPSs intermediates. Specially, the NiDME additive captures LiPSs in the electrolyte, accelerates the redox reactions homogeneously and regulates a uniform and fast deposition of Li2S, all these contributing to a perfect catalytic cycle with less LiPS shuttling. This work deepens our understanding on catalysis in accelerating sulfur redox conversion and indicates homogeneous catalysis as a simple yet fundamental solution to shuttle effect of LiPSs intermediates, which boosts practical Li-S batteries with less electrolyte needs and long working life.

Three new cyclometalated iridium(III) complexes [(cf3piq)2Ir(N∧N)][PF6] (Ir1–Ir3) have been synthesized and characterized. The solid structure of Ir1 has been determined by X-ray crystallography. T...

The Zhaotong National Shale Gas Demonstration Area along the southern margin of the Sichuan Basin is located in the complex marine tectonic area of South China, where shale deformation and reformation are intense and the factors controlling sweet spots are complex, so the preservation conditions have an important impact on the enrichment of shale gas. In order to support the selection and evaluation of shale gas sweet spots in this area and improve the success rate of drilling, this paper carried out a geological survey on field outcrops. Then, based on drilling, mud logging and physical property test data, the structural deformation pattern and the regional deformation characteristics of this demonstration area were analyzed, and the development characteristics of formation joints and fractures, the sealing capacity of shale surrounding rock and the distribution characteristics of gas reservoirs were studied. Finally, the preservation conditions of shale gas in the Wufeng Formation of Upper Ordovician and the Longmaxi Formation of Lower Silurian were discussed. And the following research results were obtained. First, in the Zhaotong National Shale Gas Demonstration Area, three structural deformation patterns are developed from south to north, including trough type, equal amplitude type and baffle type, which are distributed in three major deformation zones, respectively, i.e., the shear deformation zone of Central Guizhou Uplift, the compression–torsion deformation zone of northern Yunnan–Guizhou Depression and the compression deformation zone of Southern Sichuan Depression. Second, three types of joints and fractures whose relationships with the direction of strata are high angle, middle–low angle and bedding intersection are developed in the Wufeng–Longmaxi formations and its overlying strata, and their occurrence characteristics are basically consistent with those of the three major deformation zones. Third, the shale of Wufeng–Longmaxi formations is thick in the north and thin in the south and possesses the preservation conditions of source–reservoir integration and self-sealing hydrocarbon accumulation. And combined with the sealing ability of the overburden strata and the roof and floor, its preservation conditions are overall better. Fourth, from the perspective of shale gas component, this area can be divided into three belts, i.e., methane, methane + nitrogen mixture and nitrogen from north to south. And the preservation conditions of shale gas are generally better in the north and worse in the south. In conclusion, the shale in the central–northern part of Zhaotong National Shale Gas Demonstration Area (compression deformation area and its southern margin) is the most favorable area because of its large shale thickness, weak reformation and deformation, bedding development of joints and fractures, good sealing performance and excellent preservation conditions. The compression–torsion deformation zone of northern Yunnan–Guizhou Depression in the central part is moderate in preservation conditions, and it is the relatively favorable area. The shear deformation zone of Central Guizhou Uplift in the southern part has poor preservation conditions, and it is a prospective area.

As an important pilot target for shale gas exploration and development in China, the Longmaxi Formation shale in the Dianqianbei Area is characterized by high content of nitrogen, which severely increases exploration risk. Accordingly, this study explores the genesis of shale gas reservoir and the mechanism of nitrogen enrichment through investigating shale gas compositions, isotope features, and geochemical characteristics of associated gases. The high-nitrogen shale gas reservoir in the Longmaxi Formation is demonstrated to be a typical dry gas reservoir. Specifically, the alkane carbon isotope reversal is ascribed to the secondary cracking of crude oil and the Rayleigh fractionation induced by the basalt mantle plume. Such a thermogenic oil-type gas reservoir is composed of both oil-cracking gas and kerogen-cracking gas. The normally high nitrogen content (18.05%–40.92%) is attributed to organic matter cracking and thermal ammoniation in the high-maturity stage. Specifically, the high heat flow effect of the Emeishan mantle plume exacerbates the thermal cracking of organic matter in the Longmaxi Formation shale, accompanied by nitrogen generation. In comparison, the abnormally high nitrogen content (86.79%–98.54%) is ascribed to the communication between the atmosphere and deep underground fluids by deep faults, which results in hydrocarbon loss and nitrogen intrusion, acting as the key factor for deconstruction of the primary shale gas reservoir. Results of this study not only enrich research on genetic mechanism of high-maturity N2 shale gas reservoirs, but also provide theoretical guidance for subsequent gas reservoir resource evaluation and well-drilling deployment in this area.

Uniform light fluence distribution for patients undergoing photodynamic therapy (PDT) is critical to ensure predictable PDT outcomes. However, current practice when delivering intrapleural PDT uses a point source to deliver light that is monitored by seven isotropic detectors placed within the pleural cavity to assess its uniformity. We have developed a real-time infrared (IR) tracking camera to follow the movement of the light point source and the surface contour of the treatment area. The calculated light fluence rates were matched with isotropic detectors using a two-correction factor method and an empirical model that includes both direct and scattered light components. Our clinical trial demonstrated that we can successfully implement the IR navigation system in 75% (15/20) of the patients. Data were successfully analyzed in 80% (12/15) patients because detector locations were not available for three patients. We conclude that it is feasible to use an IR camera-based system to track the motion of the light source during PDT and demonstrate its use to quantify the uniformity of light distribution, which deviated by a standard deviation of 18% from the prescribed light dose. The navigation system will fail when insufficient percentage of light source positions is obtained (

Based on exploration and development results and evaluation of marine shale gas in South China in the past ten years, in view of the features of “high maturity, strong tectonic reformation and high shear stress” of the shale in Zhaotong exploration zone in the Yunnan and Guizhou Plateau, as well as the key issues of long time diffusion and leakage of shallow shale gas, and the preservation conditions, the factors controlling shallow shale gas sweet spot and key zone selection evaluation technology of shale gas are investigated. From 2017 to 2018, the first significant exploration breakthrough was made in the Taiyang anticline at a buried depth of 700 to 2 000 m, discovering large-scale proved geological reserves of shallow shale gas. By examining the accumulation conditions and sweet spot control factors of the shallow shale gas in this area, it is found that the accumulation and productivity potential of shale gas in the mountainous area with complex structure outside basin are controlled by five factors: (1) The gas-rich area has weak tectonic reformation and good preservation conditions on the whole, taking on typical anticline trap occurrence mode. (2) The gas-rich area is in over-pressure state and high in shale gas content. (3) The gas-rich area has high quality shale and thus superior source rock condition. (4) The gas-rich area has high quality reservoirs dominated by class I. (5) The shale gas reservoir in the gas-rich area has high content of brittle minerals and small difference between maximum and minimum horizontal stresses which are conducive to hydraulic fracturing. The innovative practice and core technologies formed during the exploration and production capacity construction of shallow shale gas in the Zhaotong demonstration zone have great reference significance for shallow shale gas exploration and development in other areas. Key words: shallow shale gas, Silurian Longmaxi Formation, Ordovician Wufeng Formation, exploration breakthrough, Taiyang anticline area, Zhaotong area, anticline

The presented study evaluates the effect of water-table depth on groundwater evaporation (Eg) and recharge (Rg) when they occurred alternately. A lysimeter experiment incorporating a 1-year-long bromide tracer test was conducted under conditions with a range of maintained water-table depths. The results revealed that both the Rg and Eg decreased as the water table fell, until it was down to the extinction depth of groundwater evaporation (EDGE, 2.4 m). The annual quantity of Rg started to be stable at 100 mm when the water table was below the EDGE, since the maximum soil-water deficit no longer increased. When the water table was above the EDGE, Rg and Eg restricted each other and thus occurred alternately; in the wet season, >68% of the annual Rg occurred, with only

In this work, two novel electron-deficient groups phenanthrothiadiazole (PT) and triphenylenobisthiadiazole (TBT) are utilized to construct donor–acceptor–donor (D–A–D) type hole-transporting materials (HTMs). The electronic, optical and charge transport properties are evaluated by performing quantum chemical calculations. Our results show that, in comparison with that of the benzothiadiazole (BT, SM-1) unit, the newly designed SM-2 and SM-3 display more deep highest occupied molecular orbital (HOMO) energy levels. Meanwhile, the blue-shifted light absorption spectra are also obtained, which will be helpful in enhancing the absorption of the perovskite layer. Unfortunately, the hole mobilities of SM-2 and SM-3 are slightly lower than that of SM-1 due to the weak intermolecular electronic coupling. In addition, we also find that better solubility and stable dimeric configuration are obtained for the new HTMs. Overall, this work provides some useful clues for designing new acceptor structures in D–A–D-type HTMs, and a potential HTM SM-3 is proposed.

The design of new molecules with theoretical chemistry methods and further obtaining a fundamental understanding of the structure-property relationship are important for the development of high-efficiency hole-transporting materials (HTMs). Herein, the effect of semi-locked and fully-locked cores was systematically investigated based on two conformation-tunable tetrathienylethene (TTE) and tetraphenylethylene (TPE) units. Our results show that the highest occupied molecular orbital (HOMO) levels of the locked TTE-2 and TTE-3 are clearly down-shifted compared with that of the unlocked TTE-1, which is due to the decreased electronic conjugation between the locked cores and the triphenylamine (TPA) arms, whereas the same situation is not found for TPE-3 due to the twisted core configuration. Compared with the TTE-series, the TPE-series exhibits less optical absorption in the visible light region and enhanced stability. Meanwhile, the hole mobility of the designed HTMs displays an increased trend from the unlocked core to the semi-locked and fully-locked cores due to the gradually increasing hole transfer integral with enhanced molecular planarity. In addition, we also found that the reorganization energy of the locked TTE cores is obviously lowered compared to that of the unlocked one, which plays an important role in increasing the hole mobility. In summary, this work can provide some useful clues for designing high-efficiency two-dimensional HTMs, and two potential promising candidates (TTE-3 and TPE-3) are proposed.

Exploration of cost-efficient and high-performance photocatalyst for H2 evolution by using a facile approach is of great importance. In this manuscript, a facile one-pot method was employed to fabricate MoS2/CdS heterostructures with MoS2 intimately grown on the surface of CdS resulting in the formation of well-defined heterostructures. Screen experiment reveals the optimized photocatalytic H2 evolution performance of MoS2/CdS is far exceeding that of pristine CdS by a factor of more than 162. The outstanding performance can be ascribed to the formation of heterostructures which accelerate charge transportation and separation, and the MoS2 serving as a cocatalyst for the decrease of H2 overpotential. Moreover, the photocatalytic mechanism of the MoS2/CdS was carefully investigated, which contributes to the deep understanding of the photocatalytic process and the designation of other low-cost and high-efficient photocatalyst.

In this paper, we propose a novel gravity-tailored absorber to achieve two different absorption peaks at two different frequencies, whose improvement is based on the traditional sandwich structure. It is unusual that two dug grooves inside are filled with the liquid dielectrics. Since existing the gravity field, rotating this absorber in the xy plane will make the absorption peak change. In addition, this gravity-tailored absorber has a good stability of the incidence angle. The discussion of the power flow, the electric field, and structure parameters are also given to explain the physical mechanism. Compared with the existing manners of regulation, this regulation of presented absorber might be more convenient to achieve.

This is Part 2 of our work aimed at classifying the long-time behavior of the solution to a free boundary problem with monostable reaction term in space–time periodic media. In Part 1 (see [2] ) we have established a theory on the existence and uniqueness of solutions to this free boundary problem with continuous initial functions, as well as a spreading-vanishing dichotomy. We are now able to develop the methods of Weinberger [15] , [16] and others [6] , [7] , [8] , [9] , [10] to prove the existence of asymptotic spreading speed when spreading happens, without knowing a priori the existence of the corresponding semi-wave solutions of the free boundary problem. This is a completely different approach from earlier works on the free boundary model, where the spreading speed is determined by firstly showing the existence of a corresponding semi-wave. Such a semi-wave appears difficult to obtain by the earlier approaches in the case of space–time periodic media considered in our work here.

Hydrogen generation from photocatalytic water-splitting is a promising approach of renewable energy storage and has the potential to ease energy shortage. During the past few decades, various materials have been developed as photocatalysts. But most especial single photocatalytic systems still suffer from low efficiency and poor stability. Constructing heterostructures is considered as a good strategy to address those issues, but some drawbacks of safety hazard, time-consuming and energy-intensive still restrict its further application. In this manuscript, we successfully synthesized Ni2P/CdS nanohybrids by using a green and facile method. The as-synthesized Ni2P/CdS with Ni2P grown in-situ on CdS can remarkably inhibit electron–hole recombination, and thus renders more generated electrons involving in the reaction of H+ reduced into H2. As a result, the optimized Ni2P/CdS heterostructure exhibits high photocatalytic performance with H2 evolution rate of 44.65 mmol g−1 h−1, far exceeding that of pristine CdS by a factor of 127. This green synthesized strategy will inspire the fabrication of other photocatalytic systems and may low-cost, high efficient, and eco-friendly photocatalysts be obtained.

With intrinsically disordered atomic structure, metallic glasses (MGs) have been extensively studied as advanced catalysts. Although the nature of widely tunable atomic composition in MGs facilitates accommodation in different catalytic environments, it may also induce the decline of catalytic activity due to surface effect. The role of surface of MGs is still not fully understood. In this work, an Fe50Ni30P13C7 (FeNiPC) glassy ribbon was found to have a strong-binding surface layer with the superior anticorrosion but low catalytic ability. Nevertheless, an effective elimination of surface layer by chemical dealloying could highly promote the catalytic ability of FeNiPC glassy ribbons from 20 min to only 10 min for brilliant black BN dye degradation. Further investigation revealed that chemical dealloying could effectively dissolve the surface layer of FeNiPC glassy ribbons induced reactivation of surface that was previously buried under the strong oxide layer, instead of generating nano-porous structured surface. The reactivation of ribbon surface effectively optimized active reaction sites and the re-exposure of Fe, Ni and P with zero-valent state formed galvanic cells by atomic clusters leading to the acceleration of catalysis. The insight and revelation of intrinsic surface activity in this work provide an effective way to highly promote the catalytic ability of MGs.

In this article, we demonstrate a tunable ultra-broadband metamaterial absorber (TUMA) in terahertz (THz) band which is based on the multilayered structure composed of an Au reflective layer, polyimide dielectric layers, and vanadium dioxide (VO2) periodic structures, respectively. We gain the tunable absorption spectra because of the room temperature phased-changed character of VO2. The relative bandwidth reaches to 81.2% and the absorption rate is over 90% at the frequency range of 1.63–3.86 THz when the temperature (t1) is 350 K, but when t1 = 300 K, the presented absorber is acted as a reflector whose absorption is small besides the frequency points of 9.75 THz and 9.81 THz. For the sake of comprehending the physical mechanism in-depth, the electric field (E-field) diagrams, the surface current distributions and the power loss density (PLD) of the TUMA are investigated. The influences of structural arguments and incident angle (θ) on the absorption are also analyzed. The emulated consequences show that the absorption spectrum can be regulated by changing structural parameters and incident angle and the tunable absorption regions can be obtained by altering the external temperature.

Exploration of low-cost and earth-abundant photocatalysts for efficient photocatalytic H2 evolution from water is an attractive solution to the global energy and environmental problems. Although MoS2 has been proved as an efficient co-catalyst for the H2 evolution reaction (HER), controllably and accurately constructing MoS2-hybridized photocatalysts at where the electrons extracted still remains a challenge. Here, a facile two-step approach of photoetching-photodeposition has been developed to prepare MoSx/etched-CdS (Mo-Cd(e)-S) with heterostructure accurately constructed on the CdS surface defects. This structure can significantly accelerate photo-induced charge separation and transportation owing to the place of heterostructure construction matching well with that of electrons extracted, numerous active sites introduced, and shorter charge transfer path from bulk to surface. Therefore the charge recombination is significantly retarded. As a result, the Mo-Cd(e)-S exhibits outstanding photocatalytic performance with a state-of-the-art H2 generation rate of 22.5 mmol g−1 h−1 under visible light irradiation (λ ≥ 420 nm) which is 70 times higher than that of pristine CdS. This work opens a new avenue for the low-cost but high efficient photocatalysts development.

Photocatalytic water splitting is considered to be a green H2 generation approach and has potential to be applied in the future. As a photocatalytic active material for H2 evolution, CdS is a good candidate. However, the pristine CdS still suffers from low efficiency and poor stability. To address those issues, we developed noble-metal-free CdS@MoS2 core-shell nanoheterostructures which exhibit outstanding photocatalytic H2 evolution performance thus far with rate of 62.55 mmol g−1 h−1, which exceeds that of pristine CdS by a factor of 148. Meanwhile, the photocatalytic stability can be well retained with no deterioration of activity in 24 h reaction. The excellent performance can be reasonably attributed to the low crystallinity of MoS2 with numerous active sites provided, and the band alignment of CdS and MoS2 as determined by valence band-XPS and Mott-Schottky plots analysis, which significantly promotes charge transportation and separation. The enhanced photocatalytic stability here should be ascribed to the intimate growth of MoS2 shells which significantly passivate the surface trap states of CdS cores and thus the photocorrosion is remarkably retarded. This novel strategy will inspire the fabrication of other photocatalytic systems, and may high-efficient photocatalysts be obtained.

Very recently, crystallization of metallic glasses (MGs) has presented promising properties in the catalytic field. This work has investigated enhanced catalytic performance of crystallized Fe78Si9B13 ribbons for fast activating persulfate (PS) with assistance of UV-vis light and heat. The ribbons were obtained by annealing at 750°C (Fe-A750) and cibacron brilliant yellow 3G-P (BY 3G-P) dye was used as pollutant. The results indicated that UV-vis light had limited capability to enhance PS activation efficiency by crystallized ribbons while the reaction rate using heat at 65°C was 7.5 times higher than at 25°C, suggesting an advanced performance with heat assistance of Fe-A750 ribbons. Activation energy ∆E for Fe-A750 was measured as 44.5 kJ mol-1. In addition, 5 times reusability could be achieved for Fe-A750 ribbons under 45°C without catalytic decay. The surface morphologies of glassy ribbons, as-annealed Fe-A750 ribbons, HCl-treated Fe-A750 ribbons and after-reused Fe-A750 ribbons have also been systematically studied. This work provides a novel clue to promote applicability of novel crystallized ribbons from MGs.

Loofah sponge (LS) was used as carrier for high ammonia wastewater treatment with a sequencing batch biofilm reactor (SBBR), aimed at evaluating its nitrogen removal performance and durability to changeable pH and microbial corrosion. The results indicate that the average removal for COD, NH 4 + -N and total nitrogen (TN) accounted for more than 80%, 90%, and 70%, respectively, in 203 days. After SBBR operation for 108 days, the average weight loss of the loofah sponge was 49.1%. Yet, the main structure of utilized loofah sponge remained unaffected (proved by scanning electron microscopy). Moreover, based on attenuated total reflection-infrared spectroscopy (ATR-IR) and X-ray diffraction (XRD) measurements, cellulose, and hemicelluloses in the loofah sponge were reduced significantly obviously causing the proportion of lignin to increase. During the 108th to 203 days, the removal efficiencies of COD (81.6 ± 7.05%), NH 4 + -N (79.4 ± 8.82%), and TN (79.9 ± 2.85%) remained at a high level. PRACTITIONER POINTS: Loofah sponge had good durability to high ammonia and changeable pH. Lignin was the protective material of loofah sponge for resisting pH fluctuation and microbial corrosion. SBBR maintained a steady nitrogen removal performance with a low COD/N ratio.

In the present work, nitrogen-doped mesoporous carbon nanosheets (NMCNs) are prepared and extensively investigated for the oxygen reduction reaction. Initially, by using dual templates, viz. graphene oxide and a cationic surfactant, silica films (thickness: 1.0 nm) are synthesized and characterized using transmission electron microscope (TEM), nitrogen adsorption-desorption (N2 ad/des) measurements, and small-angle X-ray diffraction (SA-XRD). Morphology and structure of silica evolve along with graphene oxide concentration, while the co-operative assembly and the final structure are determined by the electrostatic interaction between the dual templates. The effect of silica template on the resultant NMCNs is investigated physicochemically by photoelectron spectroscopy (XPS), TEM, N2 ad/des and electrochemically by cyclic voltammetry (CV), and linear sweep voltammetry (LSV). NMCNs are featured of a high content of nitrogen dopant, high specific surface area (SSA) and ultrathin thickness (1.5 nm), favoring catalysis and facilitating the mass transport of the reactive species. From the electrochemical tests, it is confirmed that NMCNs yield a high oxygen reduction reaction (ORR) electrocatalytic activity in acid and alkaline environment; this activity is similar or even better as compared with the one measured over carbon supported platinum commercial catalyst (40 wt % Pt/C).

Marine shales of the Lower Cambrian Qiongzhusi and Lower Silurian Longmaxi formations are extensively distributed in the Yangtze Platform. Detailed depositional and tectonic analyses and regional mapping indicated that the organic-rich Qiongzhusi-equivalent shale was deposited in an intra-shelf low-slope environment in a passive margin setting. The Longmaxi-equivalent shale was mainly deposited in a widely-distributed intra-shelf low setting in the Upper and Middle Yangtze, and in a distal foredeep area away from clastic dilution in the Lower Yangtze Platform. The transgressive and early highstand system tracts in both Qiongzhusi and Longmaxi shales produced the best-quality shale reservoirs, with high total organic matter (TOC) content (>2%) and high quartz content (>45%). Tectonics has substantial effects on coeval deposition of organic-rich shale and its hydrocarbon accumulation and production. Later tectonism deformed the shales and disrupted early shale gas accumulation. Recent shale gas resource exploration and geologic analysis suggested that the high rate of shale gas production is due to overpressured marine shale reservoirs with high TOC and high gas content in the tectonically-stable area. Shale gas production occurred at reduced rates in slightly underpressured shale reservoirs with lower gas content in the syncline of the tectonically-transitional area deformed by three tectonic movements. There was no gas production from shales in the tectonically-active area disrupted by at least four tectonic movements and complex faults. The results of this analysis indicate that local tectonically-stable areas in the Middle and Lower Yangtze platforms may have shale gas accumulation and production potential.

The theory of the principal eigenvalue is established for the eigenvalue problem associated with a linear time-periodic nonlocal dispersal cooperative system with time delay. Then we apply it to a Nicholson's blowflies population model and obtain a threshold type result on its global dynamics.

Spontaneous solar-driven water splitting to generate H2 with no pollution discharge is an ideal H2 generation approach. However, its efficiency remains far from real application owing to the poor light-harvesting and ultrafast charge recombination of photocatalysts. To address these issues, herein, we employed a novel but simple chemical bath deposition (CBD) method to construct CdS/SrTiO3 nanodots-on-nanocubes at room temperature (ca. 25 °C). The as-synthesized nanohybrids not only expand light absorption from ultraviolet (UV) to visible light but also significantly retard charge recombination owing to the well-defined heterostructure formation. As a result, the CdS/SrTiO3 exhibits high photocatalytic performance with H2 evolution rate of 1322 μmol g−1 h−1, which is 2.8 and 12.2 times higher than that of pristine CdS and SrTiO3, respectively. This work provides a universal approach for the heterostructure construction, and inspired by this, higher efficient photocatalysts for H2 evolution may be developed in the near future.

Ni(II) coordination polymer nanosheets (Ni-CPNS) were prepared via a top-down liquid ultrasonication exfoliation method. For the first time, Ni-CPNS was used as a co-catalyst (Ni-CPNS@CdS) via a mechanical grinding strategy. The optimized Ni-CPNS@CdS catalyst reached a super high visible-light photocatalytic hydrogen production activity of 10 210 μmol h−1 g−1, exceeding that of bare CdS nanoparticles by 1480%. Our work can open new avenues towards the design of stable and cheap CPNS co-catalysts to replace expensive and rare noble metals for photocatalysis processes.

Vanadium pentoxide (V2O5), as one of the most important electrode materials for lithium ions batteries, attracts tremendous attention. Here, carbon supported V2O5 hollow nanotubes are synthesized using carbon fibers as templates through solvothermal reaction with subsequent annealing treatment. Morphological features of the samples are investigated by field-emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). X-ray diffraction (XRD) patterns confirm the formation of phase-pure structure. Elemental mapping and XPS studies are used to confirm the existence of carbon and V4+ in nanotubes. Electrochemical Li insertion behavior of nanotubes are explored as cathode in half cell configuration (vs. Li) using cyclic voltammetry, galvanostatic charge-discharge studies and rate tests. The V2O5 hollow nanotubes display a good cycling performance with a specific capacity of 237 mA h g−1 after 50 cycles at 100 mA g−1 in the voltage range of 2.0-4.0 V. Moreover, the nanotubes cathode delivers specific capacities of 165.8, 140.3 and 109.6 mA h g−1 at 1000, 2000 and 5000 mA g−1, respectively, indicating a desirable rate capability. The good electrochemical performance of carbon supported V2O5 hollow nanotubes can be attributed to the unique hollow nanotubes and the existence of carbon and V4+.

In this paper, we present a novel type of tunable gravity tailored metamaterial absorber (TGTMA) which can obtain a broadband absorption. Both seawater and oil are filled in the grooves inside the glass structures, which are the resonators of an absorber. The proposed absorber can be regulated by the gravity field, which is a brand new one compared with the previous designs. When the operating state of such a TGTMA is adjusted from one to another, a marvelous alteration of absorption can be achieved. For TM wave, the absorption band runs from 5.6 to 7.91 GHz which is over 90%, while the absorption keeps larger than 90% from 4.32 to 5.83 GHz when this absorber is rotated 180° in xy plane. The larger incident angle is the better performance of this TGTMA can be achieved. Further, the simulation results of the structure parameters are discussed. The surface current distributions, the power flows, and the power loss densities are also given to expound the physical mechanism of the proposed absorber. Importantly, compared with most of current tailoring approaches of the absorbers, the proposed method is more convenient.

N-Octyl-β-valienamine (NOV) 1 and N-octyl-4-epi-β-valienamine (NOEV) 2 are potent chemical chaperone drug candidates for the therapy of lysosomal storage disorders. Novel stereoselective syntheses of NOV 1 and NOEV 2 starting from naturally abundant (−)-shikimic acid are described in this article. The common key intermediate compound 5 was first synthesized from readily available (−)-shikimic acid via 9 steps in 50% yield. Compound 5 was then converted to NOV 1 via 5 steps in 61% yield, and it was also converted to NOEV 2 via 8 steps in 38% yield. In summary, NOV 1 was synthesized via 14 steps in 31% overall yield; and NOEV 2 was synthesized via 17 steps in 19% overall yield.

Photoacoustic (PA) imaging is an emerging biomedical imaging modality that combines the advantages of optical and ultrasound imaging. Carbon monoxide (CO), which is a vital endogenous cell-signaling molecule in the human body, exerts critical physiological functions such as anti-inflammatory, antiapoptotic, and antiproliferative. The imbalance of CO homeostasis is also associated with numerous diseases. Therefore, it is critically important to noninvasively monitor the steady-state changes of CO in vivo. However, the activatable photoacoustic (PA) probes for detecting CO-associated complicated diseases have not yet developed. In this work, we developed the first turn-on PA probe (MTR-CO) to visualize the CO level in the lipopolysaccharide (LPS)-induced acute inflammation murine model through PA imaging technology. MTR-CO is composed of a near-infrared absorption cyanine-like dye (MTR-OH) and allyl formate, showing a 10.2-fold PA signal enhancement at 690 nm upon activation by CO. Furthermore, the results revealed that MTR-CO has high sensitivity, excellent specificity, and good biocompatibility for CO in vivo. MTR-CO was then applied for PA imaging of CO in cells and for monitoring the development of acute inflammation in the murine model by tracking the changes of the CO level. These findings provide a promising strategy for accurately detecting the steady-state changes of CO in living organisms.

We propose an efficient scheme for generating spin-squeezed states at steady state in a spin-mechanical hybrid system, where an ensemble of SiV centers are coupled to a strongly damped nanomechanical resonator. We show that,there exists a collective steady state in the system, which is exactly formed by the collective spin states plus the zero excitation state of the mechanical mode. The generation of the steady spin-squeezed state is based on a dissipative quantum dynamical process in which the mechanical dissipation plays a positive role but without destroying the target state. We demonstrate that the spin-squeezed steady state can be deterministically prepared via dissipative means, with the optimal spin squeezing up to 4/N in the ideal case, where N is the number of spins. This work provides a promising platform for quantum information processing and quantum metrology., Comment: 11 pages, 8 figures

Hybrid quantum systems involving solid-state spins and superconducting microwave cavities play a crucial role in quantum science and technology, but improving the spin-photon coupling at the single quantum level remains challenging in such systems. Here, we propose a simple technique to strongly couple a single solid-state spin to the microwave photons in a superconducting coplanar waveguide (CPW) cavity via a magnetic microsphere. We show that, strong coupling at the single spin level can be realized by virtual magnonic excitations of a nearby micromagnet. The spin-photon coupling strength can be enhanced up to typically four orders of magnitude larger than that without the use of the micromagnet. This work can find applications in quantum information processing with strongly coupled solid-state spin-photonic systems., Comment: 11 pages, 5 figures

We predict a set of unusual quantum acoustic phenomena resulting from sound-matter interactions in a fully tunable solid-state platform, in which an array of solid-state spins in diamond are coupled to quantized acoustic waves in a one-dimensional (1D) optomechanical crystal. We find that, by a spatially varying laser drive that introduces a position-dependent phase in the optomechanical interaction, the mechanical band structure can be tuned in situ, consequently leading to unconventional quantum sound-matter interactions. We show that quasi-chiral sound-matter interactions can occur, with tunable ranges from bidirectional to quasi-unidirectional, when the spins are resonant with the bands. When the solid-state spins'frequency lies within the acoustic band-gap, we demonstrate the emergence of an exotic polariton bound state, which can mediate long-range tunable, odd-neighbor and complex spin-spin interactions. This work expands the present exploration of quantum phononics and can have wide applications in quantum simulation and quantum information processing., Comment: 8+11 pages, 4+9 figures, accepted for publication in PRL

Gyroporusspecies with cyanescent oxidation reactions were investigated, based on morphology and phylogenetic analysis of DNA sequences from the nuclear ribosomal large subunit (nrLSU), the nuclear ribosomal internal transcribed spacer (ITS) and the mitochondrial adenosine triphosphate ATP synthase subunit 6 (atp6). Three species, including two new species, namelyG. alpinusandG. flavocyanescensand one previously-described species, namelyG. brunneofloccosus, are revealed from China. Collections formerly reported from China as “G. cyanescens” are eitherG. alpinusorG. flavocyanescens. The new species are documented and illustrated in detail, while the concept ofG. brunneofloccosusis refined with additional recently-collected materials. Additionally, the cyanescent speciesG. pseudomicrosporus, previously described from China, is shown to be a member of the genusGyrodon, based on re-examination of the type specimen. A key to the cyanescentGyroporusspecies from China is provided.

Based on an actual engineering case, this study focused on the limit support pressure, instability mechanism, and instability failure mode of the excavation face in the sand pebble stratum...

Metallic glasses (MGs) with superior catalytic performance have recently been recognized as attractive candidates for wastewater treatment. However, further improving their performance will require knowledge of how to precisely regulate their electronic structures via compositional control. Here, two Fe-based MGs (Fe

Six new zinc(II) complexes were prepared by the reaction of ZnBr2 or ZnI2 with 4&prime, (substituted-phenyl)-2,2&prime, 6&prime, 2&prime, &prime, terpyridine compounds, bearing p-methylsulfonyl (L1), p-methoxy (L2) and p-methyl (L3), which were characterized by elemental analysis, FT-IR, NMR and single crystal X-ray diffraction. The antiproliferative properties against Eca-109, A549 and Bel-7402 cell lines and the cytotoxicity test on RAW-264.7 of these compounds were monitored using a CCK-8 assay, and the studies indicate that the complexes show higher antiproliferative activities than cisplatin. The interactions of these complexes with CT-DNA and proteins (BSA) were studied by UV-Vis, circular dichroism (CD) and fluorescent spectroscopy, respectively. The results indicate that the interaction of these zinc(II) complexes with CT-DNA is achieved through intercalative binding, and their strong binding affinity to BSA is fulfilled through a static quenching mechanism. The simulation of the complexes with the CT-DNA fragment and BSA was studied by using molecular docking software. It further validates that the complexes interact with DNA through intercalative binding mode and that they have a strong interaction with BSA.

Identifying the provenance of information posted on social media and how this information may have changed over time can be very helpful in assessing its trustworthiness. Here, we introduce a novel mechanism for discovering "post-based" information cascades, including the earliest relevant post and how its information has evolved over subsequent posts. Our prototype leverages multiple innovations in the combination of dynamic data sub-sampling and multiple natural language processing and analysis techniques, benefiting from deep learning architectures. We evaluate its performance on EMTD, a dataset that we have generated from our private experimental instance of the decentralised social network Mastodon, as well as the benchmark Microsoft Research Paraphrase Corpus, reporting no errors in sub-sampling based on clustering, and an average accuracy of 92% and F1 score of 93% for paraphrase identification.

Poly(3,4-ethylenedioxythiophene) (PEDOT) has aroused great interest in organic electrics because of its high electrical conductivity and mechanical flexibility. To improve the charge transport, it can act as an ionic liquid (IL) additive due to its ion characteristics and high electrical conductivity. Herein, we investigated the hole-transport performance of PEDOT treated by ILs featuring specific ion ratios (4 : 1, 3 : 1, 2 : 1, 1 : 1, 1 : 2, 1 : 3, and 1 : 4) of the cation and anion through classical dynamics simulations and quantum mechanics computations. The hole mobility of the amorphous PEDOT, constituting nine EDOT monomers, could be improved to 16.81, 18.03, and 10.14 cm2 V−1 s−1 when synergistically regulating the ion ratio to 2 : 1, 3 : 1, and 4 : 1. Consequently, these ratios potentially achieved nearly a 100-fold improvement in the electrical conductivity with respect to the pristine system. The improvements mainly stemmed from the fact that decreasing the amount of anions in ILs and prolonging the chain length of PEDOT yielded an ordered face-to-face π–π stacking. The electronic coupling and charge excitation further confirmed that the anions play an active role in tunneling the hole transport in ILs/heterogeneous PEDOT, and the highest occupied molecular orbital (HOMO) energy level of PEDOT was up-shifted significantly after treatment by the ratios of 2 : 1, 3 : 1, and 4 : 1, which favored the electron-donating ability and was in line with the extraordinary enhancement of the hole mobility. Our results imply that regulating the ion ratio in ILs is a novel strategy for modulating the electronic properties and π-stacked morphology of PEDOT.

Multiple absorbers that function in different absorption regions (near infra-red (NIR) and UV-Visible (UV-Vis)) have been widely used in solar cell applications to enhance the light-harvesting. Herein, two special co-sensitizing Models 1 and 2, which feature either saturated dye IQ21 or saturated co-sensitizer S2, have been added to a TiO2 surface to explore the effect of the altered sensitizing sequence, namely the co-sensitizing ratio of IQ21/S2 and S2/IQ21 on the electrostatic potential variation (ΔV), electron injection efficiency (ηinj′), and Forster resonance energy transfer (FRET), using density functional theory and first-principle molecular dynamics simulations. The ΔV related to the open-circuit voltage (Voc) is insensitive in both Models 1 and 2. However, the absorption (λabs) and ηinj′ associated with the short-circuit density (Jsc) display a significant deviation (the λabs for 1 is red-shifted compared to that of 2, and the ηinj′ for 1 is improved by 56%). Meanwhile, Model 1 manifests a suppressed FRET and potentially favors co-sensitizer S2 functioning as the electron-injector and not the energy-donor. Another two possible Models 3 and 4 that feature a reduced adsorption of IQ21 and S2 relative to 1 and 2 were considered further, and the result mirrors the main trend in 1 and 2, except for the ηinj′. Overall, it implies that sensitizing a larger absorber with NIR features to saturate it first, then introducing a smaller absorber with UV-Vis features, can potentially improve the electron injection and diminish electron–hole recombination considerably. Our results provide a comprehensive analysis of the active role of an optimized sensitizing sequence to improve the conversion efficiency.

A series of CdCl2 complexes (1a-1f and 2a-2c) with 4'-(substituted-phenyl)-2,2':6',2″-terpyridine compounds bearing hydrogen (L1a), p-methyl (L1b), p-phenyl (L1c), p-tolyl (L1d), p-carboxyl (L1e), p-fluoro (L1f), p-hydroxyl (L2a), m-hydroxyl (L2b) or o-hydroxyl (L2c), were prepared and characterized by 1H NMR, IR, elemental analysis and single crystal X-ray diffraction. All the compounds display interesting photoluminescent properties and different maximal emission peaks due to the difference of the substituent groups. The in vitro antiproliferative activities against four human carcinoma cell lines, A549, Bel-7402, Eca-109 and MCF-7, were investigated and cell viability studies indicate that the compounds have excellent results with the lowest IC50 values of 0.372 (1c), 1.003 (1c), 1.161 (1b) and 0.231 (1c) μM, respectively. The DNA interaction was studied by fluorescence titration, circular dichroism spectroscopy and molecular modeling methods. Spectrophotometric results reveal that the compounds have strong affinity binding with DNA as intercalators and molecular docking studies indicate that the binding is contributed by the π…π stacking and hydrogen bonds.

Fe-based metallic glasses have been demonstrated as effective heterogeneous catalysts in Fenton-like processes for dye degradation. Yet, currently corresponding studies have limitations due to the limited study object (dyes) and the correlation between metallic glasses and dye pollutants in Fenton-like processes is still not comprehensively studied. Accordingly, this work intensively investigated the thermal catalytic behavior correlations between two Fe-based metallic glasses (Fe78Si9B13 and Fe73.5Si13.5B9Cu1Nb3) and eight different dyes. Results indicated a lower activation energy in the more active metallic glass and a dependence of the activation energy of Fe-based metallic glasses in dye solutions. In addition, a high H2O2 concentration led to a declined catalytic efficiency but a photo-enhanced Fenton-like process overcame this limitation at high concentration of H2O2 due to the decrease of pH and enhancement of irradiation. Furthermore, the average mineralization rates of Fe78Si9B13 and Fe73.5Si13.5B9Cu1Nb3 have been measured to be 42.7% and 12.6%, respectively, and the correlation between decolorization and mineralization revealed that a faster decolorization in a Fenton-like process contributed to a higher mineralization rate. This work provides an intrinsic viewpoint of the correlation between Fe-based metallic glasses and dyes in Fenton-like processes and holds the promise to further promote the industrial value of metallic glasses.

The aim of this study was to investigate the in vivo degradation mechanism and the mechanical properties of poly(lactide-co-glycolide)/beta-tricalcium phosphate (PLGA/β-TCP) composite anchors. Anchors composed of PLGA and β-TCP were implanted in the dorsal subcutaneous tissue of beagle dogs for 6, 12, 16, and 26 weeks. The degradation of the materials was evaluated by measuring the changes in thermal behavior, crystallinity, and mechanical properties. Scanning electron microscope (SEM) was used to observe the surface and longitudinal section of the material. The evaluation of mechanical strength retention and degradation properties suggest that the addition of β-TCP particles efficiently enhances their mechanical properties and thermal characteristics and delays their degradation rate. By analyzing the results of SEM, X-ray diffraction, and differential scanning calorimetry, we can infer that after 12 weeks, the connection between β-TCP and PLGA becomes less compact, which accelerates the decline of mechanical strength.

Quality of interfaces is a key factor determining photoexcited charge transfer efficiency, and in turn photocatalytic performance of heterostructure photocatalysts. In this paper, we demonstrated CdS-MoS2/RGO-E (RGO-E: reduced graphene oxide modified by ethylenediamine) nanohybrid synthesized by using a facile one-pot solvethermal method in ethylenediamine, with CdS nanoparticles and MoS2 nanosheets intimately growing on the surface of RGO. This unique high quality heterostructure facilitates charge separation and transportation, and thus effectively suppressing charge recombination. As a result, the CdS-MoS2/RGO-E exhibits a state-of-the-art H2 evolution rate of 36.7 mmol g−1 h−1 and an apparent quantum yield of 30.5% at 420 nm, which is the advanced performance among all the same-type photocatalysts (see Table S1), and far exceeding that of bare CdS by higher than 104 times. This synthesis strategy gives an inspiration for the synthesis of other compound catalysts, and higher performance photocatalyst may be obtained.

With an intrinsically disordered atomic structure and a widely tunable atomic constituent, metallic glasses (MGs) have been extensively studied as promising catalysts in different catalytic fields. Particularly, Fe-based MGs with high catalytic activity, relatively low material cost, and environmental friendly compatibility also emerge as advanced catalysts. This review systematically discusses the recent advances of Fe-based MGs in catalytic applications, including wastewater remediation based on reductive degradation by multicomponent Fe-based MGs, oxidative degradation by introduction of advanced oxidation processes (AOPs) and nanocrystallization applied in Fe-based MGs up to date, and renewable energy conversion, with purposes of revealing Fe-based MG catalysts in the further improvement of catalytic performance and exploiting their promising catalytic abilities in a widely catalytic field.