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The synergistic interaction induced by multiphase interfaces between Cu, Co, CoS2 and S,N–C leads to excellent bifunctional oxygen reduction and evolution reaction activity and durability.

The highly crystalline S and O co-doped g-C3N4 nanosheets show outstanding performance in photocatalytic hydrogen evolution, which is attributed to the enhanced visible light absorption, high crystallinity and abundant surface active sites.

Herein, we demonstrate a self-template method to construct an efficient and stable trifunctional catalyst, where CeO2/Co nanoparticles are evenly embedded in a nitrogen-doped carbon hollow microsphere with a multi-shell nanostructure (CeO2/Co@NCH). As an electrocatalyst for the oxygen reduction reaction (ORR), it exhibits an onset potential of 0.852 V and a half-wave potential of 0.778 V versus RHE, as well as superior durability and methanol tolerance. Meanwhile, it illustrates a high activity towards the oxygen evolution reaction (OER) in 0.1 M KOH electrolyte, which only requires an overpotential of 470 mV to drive the current density of 10 mA cm−2. Moreover, the rechargeable zinc–air battery using the CeO2/Co@NCH as the air cathode electrocatalyst indicates a high round-trip efficiency with a low overpotential after 170 hours. As for overall water splitting in alkaline solution, it needs only 1.74 V to afford a 10 mA cm−2 current density with excellent long-term stability. Furthermore, a water splitting cell is integrated with rechargeable zinc–air batteries by taking advantage of the OER/ORR and OER/hydrogen evolution reaction (HER) performance of the sample, and the results present its potential as a good candidate for applications in renewable and sustainable energy conversion.

Mordenite (MOR) zeolite is known to possess a 12-membered ring (12 MR) and 8 MR channels, which are interconnected by 8 MR side pockets. Hyperpolarization (HP) 129Xe NMR reveals a new Xe adsorption...

As a class of emerging anode material, much attention has been dominated to vanadium nitride (VN) in view of its high specific capacitance, exceptional conductivity and proper operating potential window (OPW). Herein, ultra-small Ni nanoparticles (NPs) and VN NPs have been embedded in N-doped carbons (NCs) nanosheets as an anode material for supercapacitors (SCs), making the good use of the conductivity of Ni NPs and NCs nanosheets, as well as the excellent specific capacitance of VN NPs, the novel 3-Ni/VN/NCs-7 composite electrode exhibits an admirable specific capacitance of 236 F g−1 at 1 A g−1. Furthermore, the (−) 3-Ni/VN/NCs-7//CuCo2O4 (+) asymmetrical supercapacitor (ASC) and 3-Ni/VN/NCs-7 symmetrical supercapacitor (SSC) have been assembled, respectively. The (−) 3-Ni/VN/NCs-7//CuCo2O4 (+) ASC device shows a capacitance of 65 F g−1 at a large OPW of 1.8 V. More importantly, it achieves an energy density of 25 Wh kg−1 at 930 W kg−1 and a superb cycling stability (73.5% retention after 5000 cycles). Strikingly, the 3-Ni/VN/NCs-7 SSC device not only presents surpassing cycling behavior, but also possesses favorable energy density of 13.4 Wh kg−1 at a power density of 600 W kg−1, which is superior to most of the carbon-based materials.

Tailoring morphology of the support is considered to be an effective way to tune the physicochemical properties of the catalysts. Herein, we have developed a rational strategy combining of electrospinning, hydrothermal and annealing method for the first time to design well-defined hierarchical double-walled Co3O4 hollow nanofibers (CHNFs). This special tailored complicated wall structure leads to a large specific surface area, increased substrate adsorption, and improved mass transfer of reactive species, which can be employed as an ideal support for loading high-dispersed ultrafine Pt nanoparticles (PtNPs). Such a PtNPs/CHNFs catalyst exhibits an excellent catalytic activity and stability toward CO oxidation.

Highly efficient bifunctional electrocatalysts for both the oxygen reduction reaction and oxygen evolution reaction are essential for the development of rechargeable metal–air batteries. Herein, we demonstrate a novel bifunctional electrocatalyst with CeO2 and Co nanoparticles being embedded in N-doped carbon, which is achieved via pyrolyzing CeO2@zeolitic imidazolate framework-67 particles. In 0.1 M KOH aqueous solution, CeO2/Co@N-doped carbon shows an excellent electrocatalytic performance with an oxygen reduction reaction onset potential of 0.998 V vs. a reversible hydrogen electrode with an oxygen evolution reaction overpotential of 474 mV at 10 mA cm−2. The liquid rechargeable Zn–air battery that is assembled by using CeO2/Co@N-doped carbon as the air cathode shows excellent charge/discharge performance, with an open-circuit potential of 1.42 V and a maximum power density of 102.69 mW cm−2. Furthermore, the rechargeable Zn–air battery exhibits stable cycling performance at a constant current density of 5 mA cm−2 after 70 hours, with a charge/discharge gap of only 0.8 V and round-trip efficiency of ca. 59%. The remarkable bifunctional properties are considered to arise from the synergistic effect between the N-doped carbon and CeO2 nanoparticles, where abundant Ce3+ and oxygen vacancies in CeO2 are generated and more defect sites are available in N-doped carbon.

The design and synthesis of cheaper and more stable catalysts with comparable electrocatalytic performance to commercial Pt/C towards the oxygen reduction reaction is of importance for their application in fuel cells and metal–air batteries. Herein, we report the generation of nitrogen-doped carbon/MnO2 nanocomposites via pyrolyzing the polypyrrole/MnO2 precursor that is obtained based on the direct redox reaction between polypyrrole and KMnO4. The achieved sample presents an onset and half-wave potential of −0.048 and −0.124 V vs. Hg/HgO, respectively, and a current retention of 93% after 20 000 s chronoamperometry measurement. Meanwhile, it shows stronger methanol tolerance, endowing it with great potential for the corresponding applications. The excellent oxygen reduction reaction catalytic activity originates from the synergistic effect between nitrogen-doped carbon and MnO2, where the former one is helpful for MnO2 to achieve a higher Mn3+/Mn4+ ratio and a higher number of oxygen vacancies, and the existence of the latter one is beneficial for generating a higher ID/IG ratio in the carbon layer. These both contribute to the achievement of large numbers of active sites for the electrocatalytic process.

A comparative study of the adsorption and desorption processes of methanol in two kinds of nanochannels (i.e. MCM-41 and SWNTs) is performed by in situ continuous-flow laser-hyperpolarized 129Xe NMR. The high sensitivity and short acquisition time of hyperpolarized 129Xe allow for probing the molecular dynamics in a confined geometry under real working conditions. Hyperpolarized 129Xe NMR spectra indicate that the methanol adsorption behavior in nanochannels is determined by the characters of adsorption sites and that the methanol adsorption rate in the nanochannels of SWNTs is faster than in MCM-41. The experimental data shown in this work also indicate that there is a change in gas phase 129Xe NMR signal intensity during the adsorption and desorption of methanol in SWNTs. This may be because there is a strong depolarization of hyperpolarized 129Xe in SWNTs.

The human fungal pathogen Candida albicans can cause many kinds of infections, including biofilm infections on medical devices, while the available antifungal drugs are limited to only a few. In this study, alantolactone (Ala) demonstrated antifungal activities against C. albicans, as well as other Candida species, with a MIC of 72 μg/mL. Ala could also inhibit the adhesion, yeast-to-hyphal transition, biofilm formation and development of C. albicans. The exopolysaccharide of biofilm matrix and extracellular phospholipase production could also be reduced by Ala treatment. Ala could increase permeability of C. albicans cell membrane and ROS contribute to the antifungal activity of Ala. Overall, the present study suggests that Ala may provide a promising candidate for developing antifungal drugs against C. albicans infections.

In practical applications, the geological environmental monitoring instruments should have more stringent instrument properties, their resistance to high and low temperature, sealing, corrosion resistance and low power consumption, They are all have higher requirements. While the areas whitout public network coverage are mostly alpine high - altitude areas, the instruments are exposed to relatively harsh geological conditions for a long time. The timely and stable data communication transmission technology is the key technology to ensure stable operation of groundwater dynamic monitoring systems. At present, GSM short message format is mostly used in the groundwater dynamic remote monitoring technology, but this approach is extremely limited in field applications. For obtaining groundwater monitoring parameters not affected by the limitation of public wireless network coverage area, the GPRS satellite positioning and short message technology is adopted, and a kind of data transmission communication apparatus using GPRS satellite is researched. After a large number of indoor debugging and field stability tests, it is proved that the control terminal of groundwater dynamic monitoring and communication developed based on GPRS satellite communication features stable data transmission, low power consumption, good resistance of wind, sand and moisture. It solves the transmission obstacle of groundwater monitoring data in the area without mobile phone signal, and realizes multi - mode groundwater monitoring communication.

Developing non-noble metal photocatalysts for efficient photocatalytic hydrogen evolution is crucial for exploiting renewable energy. In this study, a photocatalyst of Ni2P/CdS nanorods consisting of cadmium sulfide (CdS) nanorods (NRs) decorated with Ni2P nanoparticles (NPs) was fabricated using an in-situ solvothermal method with red phosphor (P) as the P source. Ni2P NPs were tightly anchored on the surface of CdS NRs to form a core-shell structure with a well-defined heterointerface, aiming to achieve a highly efficient photocatalytic H2 generation. The as-synthesized 2%Ni2P/CdS NRs photocatalyst exhibited the significantly improved photocatalytic H2 evolution rate of 260.2 μmol∙h−1, more than 20 folds higher than that of bare CdS NRs. Moreover, the as-synthesized 2%Ni2P/CdS NRs photocatalyst demonstrated an excellent stability, even better than that of Pt/CdS NRs. The photocatalytic performance enhancement was ascribed to the core-shell structure with the interfacial Schottky junction between Ni2P NPs and CdS NRs and the accompanying fast and effective photogenerated charge carriers’ separation and transfer. This work provides a new strategy for designing non-noble metal photocatalysts to replace the noble catalysts for photocatalytic water splitting.

In this work, a series of three-dimensional porous flower-like zinc doped NiCo2 O4 (ZNCO) nanostructures with different Zn doping level are successfully prepared by a facile solvothermal process without using any templets. The obtained products are characterized by various techniques, and their electrocatalytic performances are also assessed by the oxygen evolution reaction (OER). According to the electrochemical characterization, it is demonstrated that ZNCO-0.15 (i.e., Zn0.15 Ni0.85 Co2 O4 ) nanoflowers show a lower overpotential, smaller Tafel slope, higher electrochemical active surface area (ECSA), as well as a larger turnover frequency (TOF) value than those of Co3 O4 , NiCo2 O4 , and ZnCo2 O4 nanoflowers, indicating that introduction of an optimal content of zinc ions plays an important role in enhancing electrocatalytic performances for OER. The enhanced OER performance of ZNCO-0.15 could be attributed to the increased number of active sites (Co3+ ), accelerated kinetic rate, and promoted conductivity of the catalyst with the incorporation of zinc ions.

Mesoporous zeolites have gained a great interest because of their improved performance in catalyzed reactions compared with conventional microporous zeolites. Herein, we would like to report a strategy containing sequential ammonium hexafluorosilicate (AHFS) and base treatment to prepare mesoporous Y zeolite. The obtained mesoporous Y zeolite possessed high total pore volume (0.720 cm(3) g(-1)) and mesopore volume (0.453 cm(3) g(-1)). Furthermore, the goal of well interconnectivity among different pores has also been achieved. It has been found that AHFS treatment played a crucial role in the formation of mesopores during the following base treatment procedure. Si-rich areas, which were full of defects, formed after AHFS treatment. These areas were unstable and easy to remove from the zeolite framework in base solution to generate mesopores. Meanwhile, the defects provided paths for base treatment and made it more effective. The combined treatment achieved a goal of inducing mesopores formation by defects. Catalytic performance of the zeolites were evaluated by cracking of 1,3,5-triisopropylbenzene (TIPB). The result showed that catalytic activity was closely related to the upgraded mesoporosity system of the zeolites. (C) 2017 Elsevier Inc. All rights reserved.

As a polymer semiconductor, the intrinsic structure (melon units) of graphitic carbon nitride (g-C3N4) can be modified by a facile co-polymerization approach. However, compared to the intensive research on doping or constructing a heterostructure etc., developing a co-polymerization strategy for improving the photocatalytic performance of g-C3N4 has received much less attention, owing to the lack of an appropriate polymerization route being exploited to introduce organic motifs into carbon nitride networks. In the present work, benzamide is employed as a new, low-cost co-monomer of urea to prepare the phenyl group functionalized g-C3N4 (CNPF) through a convenient one-pot thermal induction process. Introducing a phenyl group into the melon frame can essentially extend the original π-conjugation system of g-C3N4, leading to the improved visible light utilization and increased separation rate of electron–hole pairs. Furthermore, adding some benzamide into urea during the polymerization process enriches the pore structure of the as-obtained CNPF samples, resulting in a larger specific surface area. Under visible light irradiation, the as-prepared CNPF exhibits superior catalytic activity in a variety of photocatalytic systems, such as hydrogen generation from water, photo-degradation of dye and photo-reduction of Cr(VI).

Ag dendrites were readily achieved via the redox reaction between polyaniline and AgNO3 in aqueous dispersion. The diffusion-limited aggregation was adopted for the generation of dendrite structure and the oxidized polyaniline was not removed for purifying the Ag dendrites. The existence of the Ag and polyaniline was confirmed by X-ray powder diffraction patterns and Fourier transform infrared spectra. The oxygen reduction reaction activity of the product was examined with rotating disk electrode voltammetry in 0.1 M KOH aqueous solution. The presence of the polyaniline greatly enhanced the oxygen reduction reaction catalytic activity of Ag dendrites and an onset and half-wave potential of 0.846 and 0.651 V vs. reversible hydrogen electrode, respectively, were obtained. We demonstrate the possible positive effect of the template that might be ignored in many cases and this can lead us to construct series of similar catalytic systems.

Understanding the properties and behavior of water molecules in restricted geometries, such as the nanopores of rocks, is of interest for shale gas exploitation. We present herein ex situ and in situ nuclear magnetic resonance (NMR) studies on the effects of water on the adsorption and diffusion of methane in nanopores. Silica materials with one-dimensional pores of ZSM-22, MCM-41, and SBA-15, with pore sizes ranging from 0.5 to 6 nm, were chosen as models. Hyperpolarized (HP) 129Xe NMR results show that water adsorption does not affect the pore sizes of ZSM-22 and MCM-41 but reduces that of SBA-15. The presence of water suppresses methane adsorption; this suppression effect is stronger in smaller pores. The self-diffusion coefficients of methane within ZSM-22 and MCM-41 are not significantly influenced by the presence of water, as measured by 1H pulsed field gradient (PFG) NMR. However, within SBA-15, which has a pore size of 6 nm, the diffusion coefficient of methane increases as the amount of water adsorption increases, peaks, and then decreases to a constant value with further water adsorption. These experiments reveal the effects of the pore size and the presence of water on methane adsorption and diffusion in constrained spaces, which could have important implications for flow simulations of methane in shales.

CeO2 nanoparticles were incorporated into the cavity of zeolitic imidazolate framework-8 (ZIF-8) materials followed by high temperature pyrolysis to generate CeO2@N doped carbon materials. The introduction of the CeO2 nanoparticles greatly enhanced the oxygen reduction reaction (ORR) catalytic activity of the ZIF-8 derived carbon materials owing to existence of amounts of Ce3+ in CeO2 and oxygen vacancies with high chemisorbed oxygen content and the well-maintained skeleton of the original ZIF-8 with uniform mesoporous structure. The resulted sample treated at 900 oC (CeO2@N-C-900) presented an excellent ORR catalytic activity under both acidic and alkaline electrolyte. The ORR test revealed the onset and half-wave potentials of the CeO2@N-C-900 were 1.003 V and 0.908 V vs. RHE, respectively, in 0.1 M KOH aqueous solution, which were comparable to those of Pt/C catalysts. Furthermore, it displayed much better stability and methanol crossover tolerance than Pt/C, indicating its good possibility to be a good candidate for the application in energy conversion.

Eccentric encapsulation of silver by polypyrrole was realized via the direct redox reaction between AgNO 3 and pyrrole in the presence of sodium dodecyl sulfate. A facile method based on the relative amount of the Ag embedded in the normalized PPy sphere was developed and utilized to compare the interface tension between Ag, PPy and the solution. Via the aid of the embedding ratio, the formation of the eccentric silver@polypyrrole (Ag@PPy) was investigated by a temporal process and tuning the surfactant concentration and reaction temperature. Furthermore, such a unique nanostructure allowed the manipulation on the Ag end to achieve mushroom-like Au/Ag-PPy via the galvanic replacement reaction between Ag and HAuCl 4 , which was also dependent on the embedding ratio. After generating the above later nanostructure, much more active sites were available and much better catalytic activity was achieved taking the reduction of 4-nitrophenol by NaBH 4 as an example reaction.

The effects of the acid site in main channels of MOR zeolites on their product selectivity and deactivation in the MTO (methanol to olefin) reactions were investigated. The catalytic analysis demonstrates that the pyridine modified MOR zeolite yielded high selectivity (> 65.3%) of C2=-C4=, although the conversion dropped from 100% to 54%. Furthermore, both the catalytic lifetime of MOR and the stability of yielding the lower olefins were increased from less than 30 min to more than 120 min after the modification with pyridine. 1H MAS NMR on MOR and modified MOR shows that the acid sites in main channel do not benefit the productivity of lower olefins and catalysts lifetime. It can be concluded from ex-situ 13C CP MAS NMR that the deposit species during the MTO reaction depend on the pore sizes, and the formation of large alkyl aromatic species more likely occurs in the 12-ring main channels rather than the 8-ring side pocket.

The redox reaction between KMnO4 and Ni was carried out on a chain-like Ni surface under hydrothermal conditions and γ-MnO2 nanosheets were produced through this facile route. The original Ni nanochains, as cores, dominated the final morphology of the composites with MnO2 nanosheets loaded on their surface. The uniform assemblies of MnO2 , with large amounts of exposed sites, allowed them to be good candidates for application in various fields. The reduction of 4-nitrophenol by NaBH4 was selected as model reaction to test the catalytic activity of the samples and the samples could also be made into electrodes for supercapacitor measurement. Both the results revealed the advantages of the γ-MnO2 assembled on the Ni chain surfaces. Furthermore, the magnetic cores facilitated the recycling of the sample and increased the stability upon charge-discharge cycles.

Connectivity of mesopores in zeolites, which is a key factor for the high efficiency catalyst design, is still a challenge to be generated without using organic template. Herein, a hierarchical porous Y zeolite (USYB) was synthesized by introducing catalytic amounts of boron into the framework of NaY, followed by steaming. The introduction of framework boron promoted the hydrolysis of the surrounding Si O Al and Si O B bonds in steaming treatment. When the boron was dislocated from framework, it could further create more mesopores by steaming. It was deemed that boron played catalytic like role for leading to generate well interconnected mesoporosity. As a result, the mesopore volume of the zeolite increased by 46% relatively. The influence of the generated interconnected mesoporosity on the higher activity was evidenced in both iso-octane (i.e. 2,2,4-trimethylpentane) and 1,3,5-triisopropylbenzene (TIPB) cracking over USYB zeolite. Compared with conventional USY zeolite, there would be 2.1% increase in the yield of gasoline for the cracking of heavy oil over USYB catalyst.

Understanding roles of repetitive sequences in genomes of parasites could offer insights into their evolution, speciation, and parasitism. As a unique intracellular nematode, Trichinella consists of two clades, encapsulated and non-encapsulated. Genomic correlation to the distinct differences between the two clades is still unclear. Here we report an annotated draft reference genome of non-encapsulated Trichinella, T. pseudospiralis, and performed comparative analyses with encapsulated T. spiralis. Genome analysis revealed that, during Trichinella evolution, repetitive sequence insertions played an important role in gene family expansion in synergy with DNA methylation, especially for the DNase II members of the phospholipase D superfamily and Glutathione S-transferases. We further identify the genomic and epigenomic regulation of excretory/secretory products in relation to differences in parasitism, pathology and immunology between the two clades Trichinella. The present study provided a foundation for further elucidation of mechanism of nurse cell formation and immunoevasion as well as identification of phamarcological and diagnostic targets of trichinellosis.

Invasiveness of cancer cells is associated with proliferation inhibition in multiple types of cancers. Here, we identified the pivotal roles of Arginine methyltransferase PRMT7 in promoting invasion and attenuating proliferation of breast cancer cells. PRMT7 exerted its functions through binding to the scaffold protein shank2 to induce the di-methylation of shank2 at R240. Shank2 R240 methylation exposed ANK domain by disrupting its SPN-ANK domain blockade. Moreover, shank2 R240 methylation rendered recruitment of FAK that elicited the FAK auto-phosphorylation, which consequently augmented the shank2-dependent migration and invasion of breast cancer cells. On the other hand, the shank2 R240 methylation impeded proliferation of breast cancer cells by antagonizing the Ras-Raf binding via tethering the mono-ubiquitinated H-Ras. These findings characterize the PRMT7-dependent shank2 methylation as a key player in mediating reciprocal switching between invasion and proliferation, also point to the value of shank2 R240 methylation as a target for tumour metastasis treatment strategies.

Metal nanoparticles (NPs) stabilized by metal-organic frameworks (MOFs) have been intensively studied in recent decades, while investigations on the location of guest metal NPs relative to host MOF particles remain challenging and very rare. In this work, we have developed several characterization techniques, including high-angle annular dark-field scanning transmission electron microscopy (HAADF-STEM) tomography, hyperpolarized 129Xe NMR spectroscopy and positron annihilation spectroscopy (PAS), which are able to determine the specific location of metal NPs relative to the MOF particle. The fine PdCu NPs confined inside MIL-101 exhibit excellent catalytic activity, absolute selectivity and satisfied recyclability in the aerobic oxidation of benzyl alcohol in pure water. As far as we know, the determination for the location of metal NPs relative to MOF particles and pore structure information of metal NPs/MOF composites by 129Xe NMR and PAS techniques has not yet been reported., While metal nanoparticles (NPs) stabilized by metal-organic frameworks (MOFs) have been intensively studied, the determination of the location of guest metal NPs relative to host MOF particles remains challenging. Here the authors develop several techniques to determine the specific location of metal NPs relative to the MOF particles.

Highly active and stable copper catalysts were successfully achieved by in situ self-reduction treatment of hierarchical double-shell copper silicate hollow nanofibers. The coexistence of Cu0 and Cu+ species in the as-prepared catalysts demonstrated the strong metal-support interactions and endowed them with outstanding catalytic performance for the RWGS reaction.

The design and synthesis of cheaper and more stable catalysts with comparable electrocatalytic performance to commercial Pt/C towards the oxygen reduction reaction is of importance for their application in fuel cells and metal-air batteries. Herein, we report the generation of nitrogen-doped carbon/MnO2 nanocomposites via pyrolyzing the polypyrrole/MnO2 precursor that is obtained based on the direct redox reaction between polypyrrole and KMnO4. The achieved sample presents an onset and half-wave potential of -0.048 and -0.124 V vs. Hg/HgO, respectively, and a current retention of 93% after 20 000 s chronoamperometry measurement. Meanwhile, it shows stronger methanol tolerance, endowing it with great potential for the corresponding applications. The excellent oxygen reduction reaction catalytic activity originates from the synergistic effect between nitrogen-doped carbon and MnO2, where the former one is helpful for MnO2 to achieve a higher Mn3+/Mn4+ ratio and a higher number of oxygen vacancies, and the existence of the latter one is beneficial for generating a higher ID/IG ratio in the carbon layer. These both contribute to the achievement of large numbers of active sites for the electrocatalytic process.

A comparative study of the adsorption and desorption processes of methanol in two kinds of nanochannels (i.e. MCM-41 and SWNTs) is performed by in situ continuous-flow laser-hyperpolarized 129Xe NMR. The high sensitivity and short acquisition time of hyperpolarized 129Xe allow for probing the molecular dynamics in a confined geometry under real working conditions. Hyperpolarized 129Xe NMR spectra indicate that the methanol adsorption behavior in nanochannels is determined by the characters of adsorption sites and that the methanol adsorption rate in the nanochannels of SWNTs is faster than in MCM-41. The experimental data shown in this work also indicate that there is a change in gas phase 129Xe NMR signal intensity during the adsorption and desorption of methanol in SWNTs. This may be because there is a strong depolarization of hyperpolarized 129Xe in SWNTs.

In this work, we have studied the role of the 12-ring channel of mordenite in DME carbonylation. Upon modification with pyridine, the catalytic lifetime of mordenite in DME carbonylation was prolonged dramatically although its activity decreased slightly and the induction period increased. 1H MAS NMR and PFG-NMR results demonstrated that the acid quantity decreased after pyridine was adsorbed, and the self-diffusion coefficient of CH4 decreased with the increase in pyridine quantity in the 12-ring channel. 129Xe NMR results reveal that Xe atoms are preferentially adsorbed in an 8-ring side pocket at low pressure; xenon can enter the 8-ring side pocket at high temperature through the 12-ring channels only. From these results, the function of the 12-ring with respect to the reaction rate is explored and a transfer path of reactants/products is proposed.

The g-C3N4 nanosheets (g-C3N4NS) exhibit more excellent property than common bulk g-C3N4 (g-C3N4-B) due to their large surface areas, improved electron transport ability and well dispersion in water. In this work, ultrathin g-C3N4NS with a thickness of about 2.7nm have been synthesized by a simple thermal exfoliation of bulk g-C3N4, and then Ag2WO4 nanoparticles are in situ loaded on their surface to construct the Ag2WO4/g-C3N4NS heterostructured photocatalysts. Due to their unique physicochemical properties, the as-prepared heterostructures possess a fast interfacial charge transfer and increased lifetime of photo-excited charge carriers, and exhibit much higher photocatalytic activity. Under visible light irradiation, the optimum photocatalytic activity of Ag2WO4/g-C3N4NS composites is almost 53.6 and 26.5 times higher than that of pure g-C3N4-B and Ag2WO4/g-C3N4-B heterostructures towards the degradation of rhodamine B, respectively, and is almost 30.6 and 9.8 times higher towards the degradation of methyl orange, respectively. In addition, the natural sunlight photocatalytic activities of the as-prepared samples are also investigated.

In this paper, a facile strategy is reported for the preparation of well-dispersed Pt nanoparticles in ordered mesoporous silica (Pt@OMS) by using a hybrid mesoporous phenolic resin-silica nanocomposite as the parent material. The phenolic resin polymer is proposed herein to be the key in preventing the aggregation of Pt nanoparticles during their formation process and making contributions both to enhance the surface area and enlarge the pore size of the support. The Pt@OMS proves to be a highly active and stable catalyst for both gas-phase oxidation of CO and liquid-phase hydrogenation of 4-nitrophenol. This work might open new avenues for the preparation of noble metal nanoparticles in mesoporous silica with unique structures for catalytic applications.

Hierarchical hollow nanostructured MnO 2 has been fabricated using polyaniline spheres as reactive templates. The reaction between KMnO 4 and polyaniline leads to the reduction of KMnO 4 into Mn 2+ ions that are further oxidized by excessive KMnO 4 into MnO 2 layers. Meanwhile, the polyaniline cores are over-oxidized and diffuse into the solution to form the cavity. The ratio of the KMnO 4 and polyaniline plays an important role in achieving the hollow structure via establishing a reasonable diffusion/reaction rate equilibrium. Owing to the unique nanostructure, the MnO 2 electrode exhibits a specific capacitance of 308 F g −1 at a current density of 0.2 A g −1 and maintains 91% capacitance value after 3000 cycles at a current density of 2 A g −1 . An asymmetric supercapacitor assembled by the hollow MnO 2 and activated carbon presents energy densities of 20.93∼7.23 W h kg −1 under the power densities of 180∼9000 W kg −1 and 24% capacitance fading is detected after 2000 cycles at a current density of 4 A g −1 .

Highly dispersible copper nanoparticles (CuNPs) anchoring on the N-doped carbon films are achieved by pyrolyzing urea, citric acid and copper nitrate in one pot. The presence of the CuNPs and the N-doped carbon film is investigated by transmission electron microscopic, X-ray diffraction, X-ray photoelectron and Raman spectra. The citric acid is used as a carbon source to support the as-synthesized CuNPs and the urea takes a role as a nitrogen source to dope into the carbon structure and localize the CuNPs with a separated state. Such an N-doped carbon film with well-dispersed CuNPs on its surface presents an excellent catalytic performance and stability via using the reduction of 4-nitrophenol by NaBH4 as a model reaction.

Choosing a suitable two-dimensional (2D) nanomaterial as a carrier for noble metals is crucial for improving the catalytic performance and reducing the cost of nanocatalysts. In this study, we used ultrathin porous g-C3N4 nanosheets (g-C3N4-NS) as a carrier with gold nanoparticles (Au NPs) anchored on the surface. The ultrathin g-C3N4-NS was advantageous as a carrier because of its large specific surface area, abundant in-plane holes, and low cost. For comparison, 2D TiO2 nanosheets (NS), graphene oxide (GO) NS, and bulk g-C3N4 (g-C3N4-B) were also tested as carriers for the immobilization of Au NPs. Au NPs supported on different carriers were employed as catalysts for the reduction of 4-nitrophenol. The rate constant was calculated as 16.21 × 10−3 s−1 for the Au/g-C3N4-NS nanocatalyst, which was 11.4 and 42.1 times higher than those for the Au/TiO2 and Au/GO nanocomposites, respectively. Au/g-C3N4-NS exhibited excellent catalytic activity during the conversion of 4-nitrophenol with a turnover frequency of 1648 h−1. The as-prepared Au/g-C3N4-NS nanocatalyst also exhibited good catalytic performance during the reduction of 2-nitrophenol and 3-nitrophenol.

Binary transition metal sulfides hold immense promise for use in energy storage devices thanks to their higher electronic conductivity and capacity compared to that of the mono-metal sulfides arising from the richer redox reactions. Herein, hierarchically hollow C/NiCo2S4 nanosphere composites have been synthesized through carbon coating and hydrothermal processes with SiO2 nanosphere and glucose as the hard template and carbon source, respectively. The interconnected NiCo2S4 nanosheets, void spaces in the interior of nanospheres and the conductive carbon layer enable the C/NiCo2S4 composite electrode to achieve an outstanding conductivity and good stability. Accordingly, the hollow C/NiCo2S4 nanosphere electrode exhibits an extraordinary specific capacitance of 1545 F g−1, as well as an enhanced cycling stability (90.1% after 6000 cycles) at a high current density of 10 A g−1. Satisfactory energy density (34.1 Wh kg−1 at 160 W kg−1) and high power density (8000 W kg−1 at 19.8 Wh kg−1) can be obtained by fabricating an asymmetric supercapacitor with activated carbon in the operation window of 0–1.6 V. These encouraging results further reveal the promising prospects of the as-prepared C/NiCo2S4 nanocomposite for high efficient electrochemical supercapacitor.

In this work, a series of three-dimensional porous flower-like zinc doped NiCo

An understanding of active species–metal oxide support interaction is a necessary prerequisite for finely tuning the catalytic performance of Ag-based catalysts. To shed light on the interrelationship between Ag structures and acidic sites of acidic supports, a series of Ag/Al-SBA-15 catalysts with different Si/Al ratios were prepared using in situ “pH-adjusting” method and tested for catalytic CO oxidation. Of all the catalysts employed, the one with a Si/Al molar ratio of 200 (Ag/MAS 200) outperformed other catalysts in terms of activity and durability. 27 Al NMR and 1 H NMR results showed that the octahedrally coordinated extra-framework Al connected to the framework via oxygen atoms suppressed the formation of H-bonded SiOH groups, resulting in the formation of highly dispersed Ag nanoparticles with high catalytic activity. In the meantime, the presence of Ag 2 O particles formed over the framework Al with bridging hydroxyl groups considerably deteriorated the catalytic performance. However, the Ag/MAS 200 catalyst exhibited a striking feature: that is, the bulk Ag 2 O species are easily reduced by CO at room temperature, leading to “ in situ formation” of metallic Ag particles during CO oxidation even in the presence of high concentration of O 2 . This unique property caused the induction period (ca. 270 min) and gradually enhanced the catalytic activity, eventually reaching a high and steady-state CO conversion (85%).

The polymerization of aniline was realized in a confined space by using CeO2 nanoparticles as reactive templates that were encapsulated by SiO2. The weak solubility of CeO2 in acidic solution, resulting in the slow release of Ce4+ ions with a high oxidizing potential, and the porous structure of the SiO2 shell allowed an equilibrium to be established between the diffusion of aniline inward and Ce4+ ions outward from the shell, and the polymerization of aniline in the cavity. The influence of the shell thickness, reaction temperature and aniline concentration on the generation of the yolk–shell nanostructures was investigated in detail. By virtue of the excellent photothermal property of polyaniline that was confined in the SiO2 shell, the product was applied in drug loading and photothermal release using 5-fluorouracil as a representative anticancer drug.

It is of great importance to prevent catalysts from aggregating in order to maintain their high activity and stability for various applications. Based on a typical sacrificed SiO2 template route, gold nanoparticles (AuNPs) stabilized on an Fe3O4@SiO2 surface were anchored onto the inner layer of a polyaniline (PANI) shell, endowing a protection effect to avoid direct contact with the aiming molecules. The existence of the Fe3O4 core allowed the facile recycling of the catalysts from the reaction system. Compared to the sample without the protection of the PANI shell, Fe3O4@Au–PANI presented a much higher catalytic stability using the reduction of 4-nitrophenol by NaBH4 as a model reaction.