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Metallic group VIB transition metal dichalcogenides (1T-TMDs) have attracted great interest because of their outstanding performance in electrocatalysis, supercapacitors, batteries, and so on, whereas the strict fabrication conditions and thermodynamical metastability of 1T-TMDs greatly restrict their extensive applications. Therefore, it is significant to obtain stable and high-concentration 1T-TMDs in a simple and large-scale strategy. Herein, we report a facile and large-scale synthesis of high-concentration 1T-TMDs via an ionic liquid (IL) assisted hydrothermal strategy, including 1T-MoS

China has focused on the exploration and development of shale gas resources to reduce its reliance on coal and shift to cleaner energy sources. While significant progress has been made in the Sichuan Basin, unlocking the shale gas potential in other regions of South China has proven challenging due to the complex geology and mountainous terrain. In 2021, Well QSD-1 was deployed in southwestern Guizhou and achieved a daily shale gas flow of 11,011 m3 in the Dawuba Formation, marking the first time an industrial gas flow had been obtained from shale gas drilling in the marine strata of the Upper Paleozoic in China. This breakthrough has deepened the understanding of the southern China Carboniferous marine strata and highlighted key aspects of the formation: (1) Sedimentation occurred in alternating platforms and basins, with most organic-rich shale developed in sloping and basin areas; (2) the formation exhibits favorable static indicators, with a relatively thick section (over 200 m), and an organic carbon content of approximately 1%; (3) the intercalation of argillaceous limestone and shale intervals is conducive to the preservation of shale gas within the formation. These results demonstrate the potential for the Upper Paleozoic in South China to become a significant shale gas producer, which could contribute significantly to China’s energy security. Furthermore, exploring shale gas in the region may have positive economic and environmental impacts, including reducing China’s dependence on coal and decreasing greenhouse gas emissions.

The rational design and construction of noble metal-free electrocatalysts featuring high efficiency and low cost are important for the hydrogen evolution reaction (HER). A significant development in the synthesis of a loofah-like Co

Pore structural characteristics and methane adsorption capacity are two significant aspects affecting shale gas potential, but the impact of deposition and burial processes on these two aspects is not clear. Hence, the shale samples of Taiyuan Formation deposited continuously and experienced multi-stage tectonic uplift in Fuyang-Bozhou area of Southern North China Basin were collected in this study. Based on the total organic carbon content analysis, mineral composition determination, low-pressure CO2 and N2 adsorption, high-pressure methane adsorption and argon ion polishing-field emission scanning electron microscope observation. The impact of depositional and burial processes variation on shale reservoir physical properties and adsorption performance is studied. The results display that the pore types of shale samples which were continues deposited and experienced multi-stage tectonic uplift have no obvious differences, while the pore volume as well as specific surface area (SSA) of micropores and mesopores of shale samples under multi-stage tectonic uplift are larger significantly. Meanwhile, the roughness of shale pores increases also. The decrease of loading pressure caused by multi-stage tectonic uplift may be the main factor for the pore structure changes of shale sample. Compared with the continuous deposited samples, the shale samples under multi-stage tectonic uplift have stronger methane adsorption capacity, which is relevant to the greater SSA of micropores as well as mesopores. This study provides an example and new revelation for the influence of depositional and burial processes on shale pore structure and methane adsorption capacity.

High-entropy perovskite oxides (HEPOs) are attracting significant attention due to their unique structures, unprecedented properties and great application potential in many fields, while available synthetic methods have many shortcomings; so it is still a challenge to develop a simple, low-cost and environment-friendly synthetic strategy for HEPOs. Herein, a novel synthetic strategy is reported for HEPOs using an ionic liquid (IL)-hydroxide-mediated technique at a low temperature and normal atmospheric pressure. The synthesized HEPOs, including Ba(FeNbTiZrTa)O

The development of three-dimensional (3D) hierarchical mesoporous architectures comprising two-dimensional (2D) thin nanosheets to improve the electrochemical performance of asymmetric supercapacitors (ASCs) is of great significance. Herein, we report a simple ionothermal strategy that uses an ionic liquid (1-butyl-3-methylimidazolium chloride) as the solvent to synthesize a Ni3Se2 3D hierarchical mesoporous nanosheet network (HMNN) in two stages: the formation a one-dimensional (1D) NiSe-nanorod framework and its subsequent transformation to the Ni3Se2 3D HMNN. The as-synthesized Ni3Se2 3D HMNN with a large specific surface area and a well-developed mesoporous structure can provide more active sites for redox reactions and promote electrolytic penetration and charge transfer, thereby achieving excellent electrochemical performance. The Ni3Se2 3D HMNN exhibits a high specific capacitance of 801 F g−1 at 3 A g−1 and superior cycling stability (retaining 80.2% of its specific capacitance after 10 000 cycles at 10 A g−1). Furthermore, the Ni3Se2 3D HMNN-based ASC exhibits a high energy density of 38.4 W h kg−1 at a power density of 794.5 W kg−1 and outstanding cycling stability (retaining 71.4% of its specific capacitance after 10 000 cycles at 2 A g−1). Impressively, two such ASC devices connected in series can light up an LED for ∼50 min, suggesting their great potential in high-performance ASCs.

Due to the lack of effective paleo-geothermometers, it has often been difficult to reconstruct the thermal history of marine carbonate strata, resulting in unreliable conclusions. As emerging paleo-geothermometers, the clumped isotope of carbonate rocks could directly provide the temperature information without relying on the assumed isotopes of paleo-fluids, which has shown excellent potential in the study of the thermal history of carbonate reservoirs. To exclude the interference from late diagenesis, this study examined multiple carbonate samples under minor diagenetic alteration, which were selected from several wells in the Tarim Basin and Sichuan Basin to examine the clumped isotope (measured as Δ47 values). Considering the temperature range and acid fractionation factors of various clumped isotope formulae, the Deflieses formula was selected to calculate the temperature of clumped isotope. By analyzing the experimental results, the meaning of Δ47 temperature in the naturally evolved limestones and dolomites, the reordering rules of 13C–18O solid-state bond in calcite clumped isotope, and the effects of thermal history on clumped isotope in different lithologies have been comprehensively discussed herein. The Shun-Ka area located in the center of the Tarim Basin has been subjected to simple tectonic movements and continuous subsidence, because of which the strata of this area are currently experiencing the highest burial depth and temperature, which provide ideal conditions for studying the influence of temperature on Δ47 values. The measured Δ47 values of 17 samples from the Shun-Ka area were in the range 0.443‰–0.634‰, and the calculated temperatures of the clumped isotope were in the range 49.9–201.7°C. The Δ47 temperatures of these samples were higher than their diagenetic temperatures, indicating that Δ47 was affected by the burial process with the reordering of solid-state 13C–18O bonds. Based on the relationship between the Δ47 temperature and borehole temperature in the Shun-Ka uplift of the Tarim Basin, it was suggested that the "blocking temperature" of 13C–18O solid-state bond reordering in the naturally evolved calcites would not be higher than 120°C and the "equilibrium temperature" would not be lower than 160°C, which was consistent with the foreign laboratory results. Furthermore, to compare the effect of clumped isotope in different lithologies, another 11 dolomite samples were selected from the central uplift of the Sichuan Basin for analyzing the clumped isotope. The measured Δ47 values of dolomites from the Sichuan Basin were in the range 0.423‰–0.537‰, and the calculated temperatures of the clumped isotope were in the range 105.7–233.5°C. Similarly, it is possible that the warming effect associated with increased burial depth resulted in 13C–18O solid-state bond reordering and a higher temperature, which was the result of both diagenesis and burial heating. To investigate the effects of thermal history on clumped isotope, the first-order approximation model was used to simulate the clumped isotope values based on the thermal history reported in previous research. The initial diagenesis temperature was set to 20°C, and it was assumed that the Δ47 temperatures of samples were only affected by diagenesis temperature and thermal history. Results revealed that the Δ47 temperature calculated using the first-order approximation model of limestone samples from the Yingshan Formation of the Tarim Basin exhibited good agreement with the measured temperature, but the calculated Δ47 temperature in the dolomites considerably differed from the actual measured temperature. This conflict could have occurred due to various thermodynamic properties (such as frequency factors and activation energy) and the complex diagenesis process between limestones and dolomites. Therefore, the first-order approximation model could be used more accurately to describe the effect of the basins thermal history on 13C–18O solid-state reordering in calcites. However, further research should be conducted on dolomites to build an inversion model focusing on the thermal history of the basin and clumped isotope.

Reconstructing the evolution of paleofluid pressure in carbonate reservoirs is a challenging problem, particularly when no oil-bearing fluid inclusions are available to provide barometric constraints on the fluid system. To recover the paleofluid pressure in the Sinian Dengying Formation (Z2dn) and the Cambrian Longwangmiao Formation (Є1l) of the central paleo-uplift of the Sichuan Basin, we conducted a comprehensive analysis combining the inclusion pressure-volume-temperature simulation, inclusions in situ Raman shifts, and basin modeling. The results showed that the evolution of the pore pressure could be divided into four stages. Prior to the end of the late Triassic, the whole central paleo-uplift was in a normal pressure state. During the Jurassic, a moderate overpressure prevailed in the dolomitic reservoirs of the Gaoshiti-Moxi area and decreased in the adjacent units. At the end of the early Cretaceous, the overpressure reached a maximum in the whole region and was strongest in the Longnusi area, decreasing to the west. From the late Cretaceous to the present day, the central area of the basin has uplifted rapidly with the overpressure significantly decreasing. Z2dn has been restored to normal pressure during the Neogene, while Є1l remains moderately overpressurized. Based on an analysis of the structural background and preservation conditions, the types of sedimentary facies, the preservation condition of the traps, and the differential weathering process are the primary reasons for the different pressure states in Z2dn and Є1l during the last stages.

The Sichuan Basin is among the basins with the most abundant oil and gas resources in China. The Sinian and Cambrian strata are the most important source rocks. Previous studies of the thermal history of the central Sichuan Basin have focused on the Late Paleozoic and studies of the Early Paleozoic thermal history are not available in literature and the thermal evolution of the Sinian and Cambrian source rocks are yet to be examined. A new thermal history was reconstructed using integrated thermal indicators, including apatite and zircon (U-Th)/He, zircon fission tracks, and equivalent vitrinite reflectance. The modeled results indicated that the heat flow was relatively low (

Recently, trillions of cubic meters gas resources have been found in Sinian reservoirs of Gaoshiti-Moxi region in the central uplift of Sichuan Basin, which is the first commercial discovery of primary gas field in Precambrian anywhere in the world. To obtain a great breakthrough in Precambrian hydrocarbon exploration, it is necessary to find out the evolution process of temperature and pressure. Reconstructing the thermal history and pore pressure evolution in carbonate reservoirs are challenging problems, especially in deep-old layers without available samples and methods. To study the temperature and pressure system, we conducted a comprehensive analysis combining the paleo-thermal indicators and inclusions Pressure-Volume-Temperature (PVT) simulation with basin modeling. The results showed that the thermal history of the Gaoshiti-Moxi area could be divided into three stages. From the Late Sinian to Late Paleozoic, the thermal regime was stable with low heat flow value (

The construction of graphene-based composites is a novel electrode material design strategy and has become a promising field in new energy material research. However, the rational design principle is still poorly understood, and the synthetic technology urgently needs to be expanded. Here, a novel strategy for the synthesis of a reduced graphene oxide (rGO)/VS4 nanoparticle (NP) composite is reported using an ionic liquid (IL)-assisted hydrothermal method. The synergistic effects of graphene and IL, which include the π–cation/anion interactions of graphene, the capping agent effect of IL, and their π–π stacking interaction, are responsible for the synthesis of the composite, achieving delicate tailoring of VS4 NPs as well as their homogeneous dispersal on the surface of rGO nanosheets. The superior nanostructure of the composite results in enhanced lithium-ion storage performance, such as improved cyclic stability (1009 mA h g–1 at 0.1 A g–1 after 150 cycles and 788 mA h g–1 after 240 cycles even at 1 A g...

Reasonable design of non-precious metal electrocatalysts with high catalytic activity plays a crucial role in promoting the sustainable development of hydrogen energy. Herein, to improve both the active sites and intrinsic conductivity of molybdenum disulfide (MoS2), a facile ionic liquid-assisted hydrothermal method and subsequent phosphorization treatment are fabricated for advanced electrochemical hydrogen evolution reaction (HER) performance. The obtained P-CoS1.097@MoS2/CC heterostructure exhibits a low overpotential of 98 mV and 88 mV at the current density of 10 mA cm−2 in 0.5 M H2SO4 and 1 M KOH, respectively. The remarkable performance is due to the synergistic effects of the constructed heterogeneous interface between CoS1.097 and MoS2 as well as sulfur vacancies generated by the phosphorus doping. Therefore, fast electron transfer and large number of catalytic active sites can be achieved by means of such advantageous strategy. This research paves the way for the development of MoS2-based catalysts through the cooperative design of doping and interface engineering toward efficient HER process.

The application of hybrid materials with well-designed composition and morphology is an effective approach towards enhanced electrochemical performance of asymmetric supercapacitors (ASCs). Here a facile two-step growth-annealing strategy to construct a NiSe/MoSe2/MoO2 three-dimensional (3D) hierarchical hollow architecture comprising two-dimensional (2D) thin nanoflakes is reported. The reaction time and Ni/Mo mole ratio of precursor are crucial for the construction of NiSe/MoSe2/MoO2 3D hierarchical hollow microsphere (HHM). The as-synthesized NiSe/MoSe2/MoO2 3D HHM with large specific surface area and well-developed mesoporous can increase contact area between active material and electrolyte, and shorten the path and time for electrolyte ions transport, thereby achieving outstanding electrochemical performance. The NiSe/MoSe2/MoO2 3D HHM shows a high specific capacitance of 1061 F g−1 at a current density of 2 A g−1, exceptional rate capability (maintaining 57% of its initial capacitance at 20 A g−1) and stable long-term cycling performance (retaining 93.9% of its initial capacitance after 10,000 cycles at 3 A g−1). Moreover, the NiSe/MoSe2/MoO2 3D HHM-based ASC provides a high energy density of 48.1 Wh kg−1 at a power density of 428 W kg−1, and still maintains 20.4 Wh kg−1 even at a high power density of 7.3 kW kg−1, suggesting its great potential in superior-performance ASCs.

A simple and effective red phosphorus self-templated wet-chemical method was proposed to fabricate hierarchical nanoporous metal phosphides, whose pore sizes and porosities can be easily modulated by changing the addition of ionic liquids (ILs). The resultant products possess large specific surface areas (206.8 m2 g−1) and big pore volume (0.7145 cm3 g−1 nm−1), which endowed the as-synthesized nickel phosphides with outstanding electrocatalytic activities for OER in terms of Tafel slopes (46 mv dec−1), the operating potential at the benchmark current density of 10 mA cm−2 (246 mV) and long term electrocatalytic stability. These interesting results will promote the use of ILs as controlling agent for the preparation of porous catalysts in the electrocatalytic OER and the development of synthesis of porous nanomaterials.

The paper analyzed the methods of extracting information from the network traffic, among which the information extraction based on the Tag marker was studied in depth. Tags, which contain specific core words, can be considered as markers of different types of information. Due to the non-standardized nature the Tag marker, a Tag often has lots of interference characters and the traditional pattern matching algorithm may leads to mismatch or poor performance. After analyzing the network service tag characteristics, we presented the Tag word segmenting method and the concept of Tag semantic distance. By introducing the tag semantic distance concept, we improved the Aho-Corasick algorithm to identify the tags which we concerned in extracting network service information. This improved algorithm, SemAC, is based on tag words segmenting and semantic distance calculation by dual-way scanning on words-map. Using this improved AC algorithm based on pre-defined core words, we successfully identified the tags and extracted what we need from the packets stream of web sites. At the end of this paper time complexity is analyzed.

Identification of Chinese coding type is a major and challenging issue in Chinese web content audit and analysis. In this paper we develop a novel algorithm based on the theory of Kolmogorov complexity to identify the coding type of Chinese characters of a given text segment. An array of text compressors are used as filters to evaluate the information distance of text under examination and the training corpus coded in different coding type. The information distance can be used to decide the coding type according to the Kolmogorov theory. In this paper a particular compressing algorithm is used to minimize computing complexity by separating coding book training stage and compressing stage. Finally, we present the experimental results through which the accuracy and performance of the algorithm is confirmed. The result also proves that this algorithm is especially efficient when short text segment is under examination comparing with the n-gram algorithms.