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Lithium-sulfur (Li–S) batteries are a promising candidate for renewable next-generation energy storage technologies with low cost and high performance. However, their performances are limited by the “shuttle effect” of polysulfides. Herein, a bifunctional hierarchical structure of three-dimensional titanium nitride (TiN) nanowire array (NA) with exposed (200) facets is prepared as an efficient polysulfide-anchoring center. Benefitting from this chemical tailoring strategy, the TiN-NA-based electrode not only provides stable well-dispersed and highly ordered nanowires to accelerate the efficient transition of redox charge carriers and to further promote the redox kinetics of polysulfide conversion, but also suggests five-coordinated Ti sites on (200) facets to enhance the adsorption ability for polysulfides. With the advances of the newly developed materials, liquid Li2S6-based TiN NA electrodes (area: 2 ​cm2) offer large initial capacities of 1214 and 1150 mAh/g, and hold 856 and 520 mAh/g with 1.0 and 3.0 ​mg/cm2 sulfur loadings at 1.6 ​mA/cm2 after 500 cycles, respectively. Specifically, the Galvanostatic intermittent titration technique suggests a strong adsorption capacity of TiN-NA-based electrodes in artificial strong polysulfide diffusion conditions during discontinuous charging and discharging processes. This work offers a novel concept of tailoring uncoordinated Ti sites and optimizing electron transfer in polysulfide redox reactions to effectively tackle the “shuttle effect”.

Morphological, electrochemical, and photovoltaic stabilities of the poly[benzodithiophene-bis(decyltetradecyl-thien) naphthothiadiazole] (PBDT-DTNT):phenyl-C61-butyric acid methyl ester (PC71BM) solar cells were promoted by the pre-designed supramolecules on the basis of reduced graphene oxide (rGO) nanosheets. Nanostructures consisted of the pristine rGO, grafted-rGO/PBDT-DTNT, rGO-polythiophene (GPTh) electrospun nanofiber, grafted-rGO/PBDT-DTNT electrospun nanofiber and rGO/PBDT-DTNT samples. The reduction in photovoltaic characteristics during air aging was the steepest for the unmodified PBDT-DTNT:PC71BM solar cells. From rGO based photovoltaics towards the rGO/PBDT-DTNT modified ones possessing the well-patterned PBDT-DTNT nanofibers, the slopes of graphs decreased. The most stabilized devices were fabricated on the basis of PBDT-DTNT:PC71BM:rGO/PBDT-DTNT active layers (power conversion efficiency (PCE) from 6.09% for upon-fabricated to 4.87% for 1 month aged systems) for having the most red-shifted and intensified absorbance, the largest phase separation, the lowest impedance responses and the highest photovoltaic characteristics during 1 month air aging (short circuit current density (Jsc) of 12.09 mA/cm2, fill factor (FF) of 63%, open circuit voltage (Voc) of 0.64 V, hole mobility (µh) of 5.3 × 10–5 cm2/V s, electron mobility (µe) of 7.9 × 10–4 cm2/V s, charge transfer resistance (Rtr) of 431 Ω cm2 and PCE of 4.87%). The GPTh/PBDT-DTNT/PC71BM (Jsc = 10.31 mA/cm2, FF = 49%, Voc = 0.55 V, Rtr = 796 Ω cm2 and PCE = 2.78%) and grafted-rGO/PBDT-DTNT/PBDT-DTNT (Jsc = 10.98 mA/cm2, FF = 56%, Voc = 0.60 V, Rtr = 539 Ω cm2 and PCE = 3.69%) electrospun nanofibers also imparted the stabilization of devices within 1 month.

Potassium-ion batteries are regarded as the low-cost alternative to lithium-ion batteries. However, their development is hampered by the lack of suitable electrode materials. In this work, we demonstrate that MoS2 with expanded interlayers represents a promising candidate for the electrochemical storage of potassium ions. Hierarchical interlayer-expanded MoS2 assemblies supported on carbon nanotubes are prepared via a straightforward solution method. The increased interlayer spacing not only enables the better accommodation of foreign ions, but also lowers the diffusion energy barrier and improves diffusion kinetics of ions. When investigated as the anode material of potassium ion batteries, our interlayer-expanded MoS2 assemblies exhibit an excellent electrochemical performance with large capacity (up to ∼ 520 mAhg−1), good rate capability (∼ 310 mAhg−1 at 1,000 mAg−1) and impressive cycling stability, superior to most competitors.

There is an increasing awareness of the need to pursue energy solutions with a low carbon footprint. The conventional power generation process (e.g. combustion of fossil fuels) is typically accompanied by CO2 emission. It would be very appealing if we can reverse this trend and achieve simultaneous power generation and CO2 valorization. Herein, we demonstrate the first aqueous Al–CO2 batteries using nanostructured Bi2S3 as the cathode electrocatalyst for selectively converting CO2 to formate during discharge. Bi2S3 nanoplatelets are prepared via a facile solvothermal reaction. When measured in a flow cell configuration, they enable CO2 reduction to formate with an excellent activity (current density up to >400 mA cm−2) and selectivity (∼100%). Aqueous Al–CO2 batteries are assembled by pairing the Bi2S3 cathode and the Al anode. They exhibit an impressive power output as well as great formate production rate and selectivity at the cathode. Moreover, we demonstrate that it is possible to use scrap Al from used Al beverage cans for Al–CO2 batteries to further lower the production cost.

Li-S batteries are a promising next-generation battery technology but are confronted with a series of fundamental challenges, in particular the notorious shuttle effect of soluble polysulfide intermediates. Current research efforts are mostly focused on designing proper host materials for the entrapment and immobilization of polysulfides. Herein, we demonstrate that electrocatalysis may play an unexpected role in Li-S batteries. Nanosized tungsten carbide particles dispersed on the carbonaceous support are prepared from the pyrolysis of phosphotungstic acid-functionalized metal-organic frameworks. Both experimental measurements and theoretical calculations demonstrate that they not only have strong affinity toward polysulfide intermediates, but also significantly accelerate the reduction of low-order polysulfides that is otherwise kinetically challenged. Using these supported tungsten carbide nanoparticles as the cathode catalyst, our Li-S batteries achieve large capacity, excellent cycling stability and impressive rate capability.

Photoelectrochemical (PEC) reduction of CO2 to useful chemical feedstocks or fuels is desirable but challenging. Its performance improvement requires not only the development of suitable semiconductors and cocatalysts but also the design of efficient semiconductor–cocatalyst interface to facilitate the rapid charge transfer. Many efforts have been undertaken on the former aspect, whereas less attention is paid on the latter. In this study, we report that Bi3+-assisted chemical etching of Si wafers affords efficient and robust Si–Bi interface for high-performance PEC CO2 reduction. Thus-formed Si/Bi photocathodes exhibit positive onset potential, large photocurrent density (∼10 mA/cm2 under 0.5 sun), and high formate Faradaic efficiency (up to 90%). In addition, we demonstrate that the photocurrent density can be further enhanced to ∼12 mA/cm2 by patterning the photocathode using photolithography to expose one-third of the Si surface without noticeably compromising the formate selectivity.

Electrocatalytic CO2 reduction to formic acid or formate is desirable but challenging due to the lack of effective and selective electrocatalysts. Among the potential candidates, Sn-based materials have attracted wide attention, but most of them, unfortunately, do not achieve high formate selectivity until at very large overpotentials. Herein, we report the self-templated synthesis of mesoporous SnO2 nanosheets as the high-performance electrocatalyst for CO2 reduction. The final product features large surface area, abundant mesoporosity and three-dimensional hierarchical order, which are beneficial for electrochemical applications. When evaluated as the CO2 reduction electrocatalyst, mesoporous SnO2 nanosheets exhibit small onset potential, large cathodic current density, high faradaic efficiency and great stability for formate production. It is most impressive that a high formate faradaic efficiency of 83% is achieved at η ∼ 710 mV, about 150–300 mV less than that discussed in previous literature results. Moreover, we integrate mesoporous SnO2 with a dimensionally stable anode, and achieve battery-driven CO2/H2O splitting to formate/O2 with decent conversion efficiency.

Development of non-precious metal based oxygen electrocatalysts, particularly bifunctional ones for both oxygen reduction and oxygen evolution is at the heart of electrochemical energy research. Layered double hydroxides have great promise, and to fulfill their full potentials requires effective strategies to engineer and stabilize their structures at the nanoscale. In this study, we report the scalable preparation and delamination of atomic-thick CoNi layered double hydroxide nanosheets, and the subsequent flocculation from their colloidal dispersion upon the introduction of negatively charged graphene oxide nanosheets. Thanks to the large surface areas of CoNi layered double hydroxide monolayers and the high electrical conductivity of reduced graphene oxide support, the thus-formed composite exhibits bifunctional activity and stability far more superior to its close competitors for oxygen reduction and oxygen evolution in both 1 M and 6 M KOH. It could also be used as the oxygen electrocatalyst of rechargeable Zn-air batteries to enable remarkable discharge peak power density and stable cycling stability.

FeCrNi/CBN cored wire is prepared by use of the pull-type flux cored wire machine (FCWM50 type), FeCrNi/CBN composite coating is made by high velocity arc spraying. The special properties of the composite coating can be improved by adding Cr, Ni and small amounts of rare earth elements to adjust the coating composition. The Tribological properties of FeCrNi/CBN composite coating with high velocity arc spraying is studied. Images and components and cross-section microstructure of coatings are analyzed by means of SEM, and EDS, etc. This research indicated that FeCrNi/CBN composite coatings have typical layered structure feature and high bond strength and hardness. Friction of coatings at near room temperature or higher has “Run-up” period. With the increase of temperature, friction coefficient of coatings becomes low and wearing capacity of coatings high. The adding of CBN powder highly improved the wearing capacity of coatings. Keywords: FeCrNi/CBN, Tribological properties, Structure feature, Wearing capacity

There is an increasing interest in the development of surface-enhanced Raman scattering (SERS) sensors for rapid and accurate on-site detection of hidden explosives. However, portable SERS methods for trace explosive detection in real systems remain scarce, mainly due to their relatively poor reliability and portability. Herein, we present the first demonstration of a portable silicon-based SERS analytical platform for signal-on detection of trace trinitrotoluene (TNT) explosives, which is made of silver nanoparticle (AgNP)-decorated silicon wafer chip (0.5 cm × 0.5 cm). In principle, under 514 nm excitation, the Raman signals of p-aminobenzenethiol (PABT) modified on the AgNP surface could be largely lit up due to the formation of electronic resonance-active TNT-PABT complex. In addition, the surface of AgNPs and silicon substrate-induced plasmon resonances also contribute the total SERS enhancement. For quantitative evaluation, the as-prepared chip features ultrahigh sensitivity [limit of detection is down to ∼1 pM (∼45.4 fg/cm

Two new platinum(II) complexes 7a and 7b with methyl hydrazinecarbodithioate derivatives of indolin-2-one have been prepared and characterized by single-crystal X-ray diffraction, NMR spectroscopy and mass spectrometry. Antiproliferative activity of the two complexes and their ligands 6a and 6b against HCT-116, MCF-7 and MDA-MB-231 cell lines was determined by the MTS assay. Complexes 7a and 7b exhibited stronger antiproliferative activity against three cell lines than compounds 6a and 6b (IC50, 1.89-5.60 versus 6.52-35.13 μM). Moreover, treatment of HCT-116 cells with the complexes resulted in an obvious sub-G1 peak by cell cycle profile analysis, and an increase of cleaved PARP1 and caspases 3, 7, and 9 by immunoblotting analysis. Live cell imaging showed that nucleus shrinkage and condensation started to appear when MCF-7 cells were treated with 7a for 8 h. Fluorescent spectrophotometric analysis revealed that the complexes physically associated with calf thymus DNA. Competitive DNA binding assays uncovered that the complexes non-covalently bind to DNA. Taken together, our results indicated that the two new platinum(II) complexes 7a and 7b non-covalently bind to DNA with high affinity and exhibit cytotoxicity against cancer cells by inducing apoptosis.

Formic acid (or formate) is suggested to be one of the most economically viable products from electrochemical carbon dioxide reduction. However, its commercial viability hinges on the development of highly active and selective electrocatalysts. Here we report that structural defects have a profound positive impact on the electrocatalytic performance of bismuth. Bismuth oxide double-walled nanotubes with fragmented surface are prepared as a template, and are cathodically converted to defective bismuth nanotubes. This converted electrocatalyst enables carbon dioxide reduction to formate with excellent activity, selectivity and stability. Most significantly, its current density reaches ~288 mA cm−2 at −0.61 V versus reversible hydrogen electrode within a flow cell reactor under ambient conditions. Using density functional theory calculations, the excellent activity and selectivity are rationalized as the outcome of abundant defective bismuth sites that stabilize the *OCHO intermediate. Furthermore, this electrocatalyst is coupled with silicon photocathodes and achieves high-performance photoelectrochemical carbon dioxide reduction., Carbon dioxide can be electrochemically reduced to form valuable chemical feedstocks, but efficiency of electrocatalysts should be improved. Here the authors report nanotube-derived bismuth for electrocatalytic reduction of carbon dioxide to formate, with performance that is enhanced by defects.

Ionic liquids (ILq) have attracted large interest among researchers due to their green nature and lower costs compared to organic solvents. Herein, we theoretically investigated the effects of changing the cationic and anionic combination of the ILqs to exfoliation of two-dimensional layer of molybdenum disulfide (MoS2). Density functional theory (DFT) and the Atoms in Molecules (AIM) analysis were performed for calculation of interaction energies and nature of interactions of ILqs with MoS2 nanosheet. Based on our results, we suggest that the intermolecular associations in the form of molecular networks in the various ILq compounds may be crucial to the solvent's intercalation and exfoliation ability. Our calculations reveal that among the nine examined ILq compounds, the highest clustering ability belongs to [Bpy][X] pairs ([X] = BF4, PF6, and Tf2N). Our results also show that the [Bpy][X] were the most efficient compounds for exfoliation of MoS2 nanosheet. As the solvent clustering increases, diffusion into the galleries of the bulk MoS2 becomes more efficient and exfoliation efficiency increases appreciably. Moreover, the calculated binding energies showed that the clustering between [Bpy][X] pairs decreased by increasing the anion size. The results found in the present study provide a framework for rational manipulation of the compositions of the ILqs for the exfoliation of the two-dimensional materials.

Three Pb(II)-edta complexes, [Pb3(edta)(H2O)Cl2]n·(H2O)3n (1), [Pb5(edta)2(H2O)2X2]n·(H2O)2n (X = Cl (2), Br (3)) (H4edta = ethylenediaminetetraacetic acid) have been synthesized by the reaction of PbX2 and H4edta under hydrothermal conditions, and were characterized by elemental analysis, thermal analysis, luminescence, powder X-ray diffraction and single-crystal X-ray diffraction. The results of X-ray crystallographic analysis reveal that these complexes are the first bilayer two-dimensional (2D) Pb-edta coordination polymers with 1D channels. The bilayers of complexes 1, 2 and 3 are linked by [Pb2Cl4], [PbCl2] and [PbBr2] clusters with carboxylate groups respectively. They are 3D supramolecular structures which are resulted from different halogenide anions. The emission spectra of 1–3 are dominated by intense and broad emission bands which are resulted from the [PbX2] clusters. Optical absorption spectra indicate that theses complexes have wide optical band-gaps and can be probably used as wide optical band-gap semiconductor materials.

There currently exists increasing concerns on the development of a kind of high-performance SERS platform, which is suitable for sensing applications ranging from the molecular to cellular (e.g., bacteria) level. Herein, we develop a novel kind of universal SERS chip, made of graphene (G)-silver nanoparticle (AgNP)-silicon (Si) sandwich nanohybrids (G@AgNPs@Si), in which AgNPs are in situ grown on a silicon wafer through hydrofluoric acid-etching-assisted chemical reduction, followed by coating with single-layer graphene via a polymer-protective etching method. The resultant chip features a strong, stable, reproducible surface-enhanced Raman scattering (SERS) effect and reliable quantitative capability. By virtues of these merits, the G@AgNPs@Si platform is capable for not only molecular detection and quantification but also cellular analysis in real systems. As a proof-of-concept application, the chip allows ultrahigh sensitive and reliable detection of adenosine triphosphate (ATP), with a detection limit of ∼1 pM. In addition, the chip, serving as a novel multifunctional platform, enables simultaneous capture, discrimination, and inactivation of bacteria. Typically, the bacterial capture efficiency is 54% at 10

Oxide monolayers supported or intermixed with an oxide support are potential nanocatalysts whose properties are determined by the interplay with the support. For fundamental studies of monolayer oxides on metal oxide supports, well-defined systems are needed, but so far, the synthesis of monolayer oxides with long-range order on single-crystal oxide surfaces is rare. Here, we show by a combination of scanning tunneling microscopy, photoemission spectroscopy, and density functional theory (DFT)-based computational analysis that the rutile TiO2(011) surface supports the formation of an ordered mixed FeTiO3 monolayer. Deposition of iron in a slightly oxidizing atmosphere (10(-8) Torr O2) and annealing to 300 °C results in a well-ordered surface structure with Fe in a 2+ charge state and Ti in a 4+ charge states. Low-energy ion scattering suggests that the cation surface composition is close to half Fe and half Ti. This surface is stable in ultrahigh vacuum to annealing temperatures of 300 °C before the iron is reduced. DFT simulations confirm that a surface structure with coverage of 50% FeO units is stable and forms an ordered structure. Although distinct from known bulk phases of the iron-titanium oxide systems, the FeTiO3 monolayer exhibits some resemblance to the ilmenite structure, which may suggest that a variety of different mixed oxide phases (of systems that exist in a bulk ilmenite phase) may be synthesized in this way on the rutile TiO2(011) substrate.

Fluorescent imaging techniques for visualization of nuclear structure and function in live cells are fundamentally important for exploring major cellular events. The ideal cellular labeling method is capable of realizing label-free, in situ, real-time, and long-term nucleus labeling in live cells, which can fully obtain the nucleus-relative information and effectively alleviate negative effects of alien probes on cellular metabolism. However, current established fluorescent probes-based strategies (e.g., fluorescent proteins-, organic dyes-, fluorescent organic/inorganic nanoparticles-based imaging techniques) are unable to simultaneously realize label-free, in situ, long-term, and real-time nucleus labeling, resulting in inevitable difficulties in fully visualizing nuclear structure and function in live cells. To this end, we present a type of bioinspired fluorescent probes, which are highly efficacious for in situ and label-free tracking of nucleus in long-term and real-time manners. Typically, the bioinspired polydopamine (PDA) nanoparticles, served as fluorescent probes, can be readily synthesized in situ within live cell nucleus without any further modifications under physiological conditions (37 °C, pH ∼7.4). Compared with other conventional nuclear dyes (e.g., propidium iodide (PI), Hoechst), superior spectroscopic properties (e.g., quantum yield of ∼35.8% and high photostability) and low cytotoxicity of PDA-based probes enable long-term (e.g., 3 h) fluorescence tracking of nucleus. We also demonstrate the generality of this type of bioinspired fluorescent probes in different cell lines and complex biological samples.

Li-CO2 batteries represent an attractive solution for electrochemical energy storage by utilizing atmospheric CO2 as the energy carrier. However, their practical viability critically depends on the development of efficient and low-cost cathode catalysts for the reversible formation and decomposition of Li2 CO3 . Here, the great potential of a structurally engineered polymer is demonstrated as the cathode catalyst for rechargeable Li-CO2 batteries. Conjugated cobalt polyphthalocyanine is prepared via a facile microwave heating method. Due to the crosslinked network, it is intrinsically elastic and has improved chemical, physical, and mechanical stability. Electrochemical measurements show that cobalt polyphthalocyanine facilitates the reversible formation and decomposition of Li2 CO3 , and therefore enables high-performance Li-CO2 batteries with large areal capacity and impressive cycling performance. In addition, the elastic and reprocessable property of the polymeric catalyst renders it possible to fabricate flexible batteries.

Taking Changguang high-sulfur coal and Yanzhou low-sulfur coal as experimental coal types, carrying out the experiment of Q-phase cement clinker co-generated from coal on two-stage polyphase reaction setup and conducting XRD analysis on the mineral composition in co-generation clicker sample, the result shows that the major mineral species in compositions of co-generation clinker are 2CaO•SiO2 and Q-phase. Taking one 330MW machine set 1004 (t.h-1) pulverized coal combustion boiler as analysis object, this paper carries out the preliminary analysis of the economic benefits that it may bring to power plant and cement enterprise by using co-generation technology. The analysis indicates that the objective boiler adopting belite Q-phase cement clinker technology, on the whole estimate of the resourceful benefit of coal fly ash and SO2 emission reduction benefit, the economic benefit of power plant obtained is 25,870 thousand yuan per year. The economic benefit cement enterprise obtained by using Belite Q-phase cement clinker to advance capacity is 40,581 thousand yuan per year.

Rayon precursors marinated by mixture aqueous solution containing NaCl and H3PO4 are activated by steam for manufacture of activated carbon fibers (ACF) in this work. It is interesting to find that mesopores (2 nm 50 nm) are greatly developed on ACF surface, which indicates that NaCl + H3PO4 aqueous solution is an effectual pore size-enlarging impregnant. The influences of the concentrations of NaCl and H3PO4 on the pore distribution and morphology of the resulting ACFs are respectively examined by scanning electron microscopy (SEM), revealing that the pore structure can be controlled through an appropriate ratio of NaCl and H3PO4 impregnation. As it has been demonstrated that the adsorptivity of the ACF is related to the fractal characteristics of the pore structure, the fractal structure of the meso/macropores in the ACF is analyzed by the small angle X-ray scattering (SAXS) method, providing the characteristics of volume, size distribution and fractal dimension (D) of the pores, Finally BET analysis has confirmed that ACFs with abundant mesopores/macropores indeed exhibit highly effective adsorption capacity.

A series of quinazolin-4(3H)-one derivatives bearing dithiocarbamate side chain at the C2-position were synthesized and evaluated for their antiproliferative activities against A549, MCF-7, HeLa, HT29 and HCT-116 cell lines. Most of the synthesized compounds exhibited broad spectrum antitproliferative activity against five cell lines, of which 5c was the most potent against HT29 cell line with an IC50 value of 5.53 μM, inducing a G2/M phase arrest in HT29 cells. Treatment of HT29 cells with 5c resulted in BubR1 phosphorylation and an increase of mitotic index in a time-dependent manner. Furthermore, 5c promoted tubulin polymerization in vitro. These results demonstrate that quinazolin-4(3H)-one derivatives bearing dithiocarbamate side chain at C2-position may be potentially novel antitumor agents targeting tubulin to activate the spindle assembly checkpoint.

Based on the J(x) fractal distribution function of aperture given by Jaroniec, this article suggests another function K(x), a variant of J(x) but offering new insight. We then use these two functions to characterize three kinds of activated carbon fiber (ACF) of different specific areas. This article also provides the fractal distribution of the aperture and the isotherm of nonpolarity benzene steam on the ACF specimens and the relationship between them.

A method to efficiently prepare substituted 1,2-dihydroquinolines and quinolines by Au(I)-catalyzed tandem hydroamination-hydroarylation under microwave irradiation was developed. This method requires short reaction time (10-70 min) and has a broad substrate scope.