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Platinum (Pt) is considered as the most efficient catalyst for hydrogen evolution reaction (HER) with a nearly zero overpotential, but it is limited by the high cost and poor stability. Herein, we report an efficient electrocatalyst of Pt–Ni alloy nanoparticles (NPs) supported on the La-modified flexible carbon nanocomposite fibers (PtNi@La-CNFs) for HER. The rare earth metal oxide in the catalyst has a structure-effect relationship with the carbon fibers to form a flexible fiber membrane. Experimental results show that the macroscopic and microscopic properties of carbon nanocomposite fibers can be optimized by doping La2O3, and the Pt–Ni NPs can be anchored effectively. The Pt1Ni1@La-CNFs electrocatalyst exhibits a small overpotential of 32 mV to achieve current density of 10 mA cm−2 with a low Tafel slope of 51 mV dec−1 in alkaline medium, outperforming that of Pt@La-CNFs and the commercial Pt/C catalyst. This study reveals that the multiple coupling effect of rare earth compound, precious metal, and transition metal in composite catalyst can tailor its the electronic configuration, and results in an enhanced HER performance. This work opens up a novel approach to design high active and low cost Pt-based HER catalysts.

The heterostructure between two semiconductor materials that had suitable band edge positions can contribute to the separation of photoelectrons and holes. In this paper, the heterostructure MoS2-C-g-C3N4 photocatalysts were in-situ synthesized at one-pot high temperature processing. The obtained 0.4 MoS2-C-g-C3N4 composites displayed the highest photocatalytic hydrogen evolution activity with a corresponding H2 evolution rate of 238 μmol g−1h−1, which was about 4.5 times higher than that of 3% C-g-C3N4, and the photocatalyts exhibited excellent stability which was used for photocatalytic hydrogen evolution reaction for 12 h. The 0.4 MoS2-C-g-C3N4 sample displayed well degradation activities for MO, MB, RhB, MR and Ar18, and the scavenging studies indicated the major involvement of ·O2– radicals in the degradation process. The enhanced photocatalytic activity of MoS2-C-g-C3N4 composite was predominantly attributed to the synergistic effects of type II heterostructure between g-C3N4 and MoS2, which effectively accelerated the transfer and separation of photogenerated charge carriers. Besides, the introduction of noble metal-free MoS2 co-catalyst further improved visible light absorption and provided more active sites for H2 evolution reaction. Such work is promising for designing a novel heterostructure photocatalysts for solar-to-fuel conversion and environmental modification.

Doping engineering is considered as a facile and effective method for improving the physical and chemical properties of CeO2. Herein, rare earth (RE) ions (La and Nd) doped Pd/CeO2 with the coaxial double-nanotube structure were manufactured by the electrospinning and high-temperature calcination. Through the doping engineering, the original morphologies of Pd/CeO2 were not destroyed and all the elements were uniformly distributed on the surface of nanotubes. XRD, Raman and UV–vis characterizations revealed that La3+ and Nd3+ ions were incorporated into the CeO2 lattice, while the cubic fluorite structure of CeO2 was maintained. Moreover, it has been proved that there were oxygen vacancies existed on the surface of CeO2 and the concentration of oxygen vacancies increased significantly as the radius of RE ions increases. In addition, an electron transfer pathway between CeO2 and Pd nanoparticles was proposed based on the experimental data and Density Functional Theory (DFT) calculations. The Pd/CeO2-La catalyst with abundant oxygen vacancies showed a high catalytic performance for Suzuki coupling reaction under mild conditions without any phase-transfer reagent, toxic solvent and inert protective atmosphere, which realizing the green catalysis.

Image caption is an important application field of artificial intelligence technique. When a machine can describe a picture reasonably like a human, it represents that the machine has higher intelligence to understand the picture. However, for complex machine learning tasks such as image caption, data annotation is time-consuming and laborious. Usually in a new application scenario, data annotation rarely results in poor model performance. A large number of easily available unlabeled image data make it possible to semi-supervised learning of image caption methods. Based on the existing end-to-end deep learning paradigm, a semi-supervised deep learning method is proposed in this paper, called N-gram + Pseudo Label NIC method. The method combines the current mainstream deep neural network method, e.g. the NIC (Neural Image Caption) model, and the semi-supervised deep learning idea of pseudo labels, and N-gram. This method generates pseudo labels by N-gram Search algorithm, and improves the effect of the model by utilizing the prior knowledge of the N-gram table and people's descriptive habits. This method has achieved better results than the original NIC model on different sub-data sets of Flickr 8K data set and MSCOCO data set of 0.5k, 1k, 2k and 3k under BLEU-1 evaluation criteria.

The demands for highly efficient and low-cost electrochemically active materials are still urgent needs for the fields of electro-catalysis and supercapacitor. Herein, a facile strategy for preparing high-efficient bi-functional electrode material was reported. The electrode material was prepared through embedding Co2P nanoparticles in the binary co-doped carbon nanofibers (Co2P@N&P-CNFs). This unique structure can effectively prevent the Co2P from detaching and provide abundant active sites. Materials prepared in this work showed the superior hydrogen evolution reaction (HER) performance with overpotential of 192 mV at a current density of 10 mA cm−2 and remarkable stability for 20 h. Moreover, the asymmetric supercapacitor (ASC) was fabricated using the Co2P@N&P-CNFs as the positive electrode material and carbon nanofibers (CNFs) as the negative electrode material, which shows an outstanding cycle stability (91.5% of the initial capacitance is retained throughout 10,000 charge-discharge tests) and a high E of 22.31 Wh kg−1 at the P of 225.02 W kg−1 at 0.3 A g−1. This work offers an effective route in designing bi-functional active materials for HER and supercapacitor.

As electrodes, two-dimensional materials show special advantages including the infinite planar lengths, broad electrochemical window, large surface–volume ratio, and much exposed active sites. In theory, the two-dimensional materials consist of the elements with high electronegativity may absorb more Na atoms, resulting in a high battery storage capacity. Based on the above idea, we selected the two dimensional metallic PS2 with 1T-Type structure as an anode material, and explored its potential applications as an electrode material for Na-ion battery through first-principle calculations. As we expected, when two dimensional PS2 is used as an anode in Na-ion battery, it can adsorb maximum three layers of sodium atoms on both sides of the monolayer, resulting in a maximum theoretical capacity of 1692 mAh/g. Furthermore, it also possesses a rather small sodium diffusion barrier of 0.17 eV, a low average open-circuit voltage of 0.18 V, and a relatively small lattice changes within 13% during the intercalation of Na. These results suggested that the two dimensional PS2 is a potentially excellent Na-ion battery anode. Our idea of designing two-dimensional anode materials with high storage capacity may provide some references for designing the next generation anode materials of metal-ion batteries.

Transition metal iron-based catalysts are promising electrocatalysts for oxygen reduction reaction (ORR), and they have the potential to replace noble metal catalysts. The one-dimensional of carbon nanofibers with tubular structure can effectively promote the electrocatalytic activity, which facilitates electron transport. Herein, the Pt–Fe/CNFs were synthesized by electrospinning and subsequent calcination. Benefiting from the advantages of one-dimensional structure, Pt–Fe/CNFs-900 with fast electrochemical kinetics and excellent stability for ORR with excellent onset of 0.99 V, a low Tafel slope of 62 mV dec−1 and high limiting current density of 6.00 mA cm−2. Long-term ORR testing indicated that the durability of this catalyst was superior to that of commercial Pt/C in alkaline electrolyte. According to RRDE test, the ORR reaction process of Pt–Fe/CNFs-900 was close to four-electron transfer routes.

Chemically fixing CO2 into the fine chemicals is a sustainable route to the utilization of CO2 and meets the requirements of green chemistry. Generally, an important intermediate, high-valued cyclic carbonates, is produced by catalyzed cycloaddition of CO2 with epoxides during the CO2 fixation. However, most of the catalysts for cycloaddition can hardly meet the standards of the green chemistry, including highly efficient, low cost, easily recoverable and recyclable etc. Therefore, in this work, an environmentally friendly composite Zn-CN/C catalyst for the cycloaddition of styrene oxide and CO2 was successfully prepared by a facile method. To this end, zinc bromide was immobilized by graphitic carbon nitride (gCN) and then supported on carbon fibers. Meanwhile, the crystal structure, types of chemical bonding, surface morphologies, and electronic transmission of the prepared catalyst were also investigated. Furthermore, the catalytic performance was evaluated by the cycloaddition reactions of styrene oxide and CO2, a satisfactory result of the moderate yield of 50–90% with a good selectivity (>99%) was obtained. Finally, a credible mechanism of the reaction was proposed.

In this work, we successfully synthesized a series of CdS-BiOCl/PAN composites by two-step method including electrospinning process and hydrothermal process. The CdS-BiOCl/PAN composites showed great photocatalytic performance and chemical stability for H2 production under UV–vis light irradiation due to the synergistic effect among CdS, BiOCl and PAN. Meanwhile, the content of CdS in CdS-BiOCl/PAN composites plays an important role in photo-catalytic abilities. In addition, according to the analysis about the photocatalyst, the possible photocatalytic mechanism and synergistic interaction were further discussed.

This paper reported a method for loading TiO2 and Pd atoms onto carbon nanofibers (CNFs) under a simple mild conditions. The catalyst prepared by the method greatly improved the reaction efficiency of Suzuki under the illumination of xenon lamp and reduced the difficulty of the reaction conditions. Compared with the previous catalysts, the catalysts developed in this paper have the characteristics of simple preparation method, easy recovery, good reaction performance, etc. The use of light energy reflected the importance of the catalyst in terms of resource utilization and environmental protection.

This study presents a field trial of ex-situ solidification/stabilization of heavy metal contaminated soils using a new hydroxyapatite based binder SPC (superphosphate and calcium oxide). The field performance including electrical conductivity (EC), heavy metal and chemical oxygen demand (COD) leachability, and penetration resistance of stabilized soils up to 256 days after treatment is investigated. Moreover, acid neutralization capacity (ANC), metal speciation, and soil mineralogy analyses are performed to elucidate the heavy metal immobilization mechanisms. The results indicate that the stabilized soils have lower EC values than untreated soils, indicating the lower soluble salt contents in stabilized soils. Ex-situ treatment can significantly reduce acid soluble fraction contents and leachability of lead, zinc and cadmium in soils as a consequence. Decrease in COD leachability is observed during the curing period up to 256 days. Additionally, SPC stabilized soils give superior mechanical properties as indicated by their higher penetration resistance values as compared to the untreated soils. The improvement in ANC and reduction in acid soluble fraction resulting from the formation of phosphate-based precipitates are mainly responsible for the reduced heavy metal leachability of stabilized soils. Additionally, ex-situ SPC treatment is found to be effective in improving soil spatial homogeneity.

In this study, in-situ treatment using dry jet mixing construction method and SPC (single superphosphate and calcium oxide) new binder are used to solidify/stabilize a heavy metal contaminated site soil with relatively high content of organic matters. Time-dependent field performance of the soils at 41 and 326 days after treatment is evaluated, which includes electrical conductivity (EC), leachability of heavy metals and chemical oxygen demand (COD), soil penetration resistance, acid neutralization capacity (ANC), and chemical speciation of heavy metals. The results indicate that the stabilized soils exhibit satisfactory performance which is comparable with the laboratory study. In-situ SPC treatment significantly decreases EC values and increases penetration resistance values of the soils. Leachability of lead, zinc, cadmium and COD decreases with increasing SPC content or curing time. Large percentages of heave metals in the soils are transformed from exchangeable fractions to residual fractions after treatment. These, coupled with the improved ANC, result in low heavy metal leachability in stabilized soils.

In this work, a novel AgI-BiOI/CNFs photocatalyst was successfully synthesized through reaction and electrospinning and carbonization processes. According to the results of XRD, XPS, SEM and TEM, BiOI and AgI nanoparticles were loaded onto the carbon nanofibers as expected. Compared with other as-prepared samples, the AgI-BiOI/CNFs(1) displayed highest photocatalytic performances and excellent recyclability, which was estimated through the degradation experiments of tetracycline hydrochloride (TC) under visible light in 3 h. TC was degraded as carbon dioxide and other small molecules. The superoxide radicals (•O2−) was proved to be the main reactive species in trapping experiments. In addition, a possible photocatalytic mechanism of samples was systematically investigated.

Carbon nanofibers supported the vanadium and copper bimetallic oxide composite electrode material has been developed successfully in this study, as the outstanding electrode materials in supercapacitors. In electrospunning and calcination processes, the organic salt of vanadium underwent high temperature decomposition to form V2O5 in situ. The various ratios of CuxO-V2O5/CNFs composite electrode material were used to apply in the electrochemical performance testing through the vacuum impregnation method. Because of the copper doping, CuxO-V2O5/CNFs (10:1) composites exhibited a specific capacitance of 867.2 F g−1 at 0.5 A g−1 over a potential range of 0–0.51 V, which surpassed those of their individual counterparts (682.5 F g−1 and 507.1 F g−1 at 0.5 A g−1 for V2O5/CNFs and CuCl2/CNF, respectively). The addition of trace copper oxide greatly improves the electrochemical performance of vanadium-based carbon fibers composites. The composites also showed good cycling stability due to the unique structure of the V2O5 and synergies with copper oxide. The preparation route provided a novel strategy to synthesize composites of transition bimetallic oxide with improving electrochemical performance for applications in supercapacitors.

Ag/carbon nanofibers and carbon nanofibers were prepared through electrospinning and high temperature carbonization. The catalyst was investigated through oxidation of styrene. The highest conversion of styrene respectively got to 98% and 70% when calcination temperature got to 1200 °C. CNFs (carbon nanofibers) have not only excellent catalytic performance but also relatively large accessible ion surface area to accommodate greater capacity and high graphitization degree to accelerate ion diffusion. CNFs exhibited excellent electrochemical performance for use as supercapacitors with high specific capacity of 271.1 F g−1 at current density of 0.5 A g−1, good rate capability and superior cycling stability over 3050 cycles.

In this work, zeolite analcime was synthesized through hydrothermal method using tetrapropylammonium hydroxide (TPAOH) as structure directing agent (SDA). And a zeolite-based copper composite catalyst was synthesized and its catalytic property was explored. Styrene oxidation was applied to evaluate the reactivity of the composite catalyst. Cu nanoparticles decorated analcime exhibited excellent activity and significant regularity in styrene oxidation. In cyclic experiments, the sustainability and stability of the composite catalyst were demonstrated. All catalysts were analyzed by a series of characterization methods.

Three-dimensional (3D) needle-like nickel carbon nanofibers (Ni/CNFs) were successfully fabricated as bifunctional materials by controlling the conditions in the preparation process. The effects such as different molar ratio, carbonization temperature and carbonization time of nanofibers morphology structures were investigated in the experiments. 3D needle-like Ni/CNFs materials as catalyst were applied in Heck reaction which exhibited a certain catalytic activity. Furthermore, this material was oxidized into the nickel and nickel oxidized (Ni/NiO) carbon nanofibers in the air atmosphere, forming electrode material. The electrochemical tests were carried out in electrolyte of 4 M KOH, and it was demonstrated that Ni/NiO-5 was the best electrode material with a high specific capacitance of 676 F g−1 at the current density of 0.5 A g−1. Cycling performance as an index of evaluation material was also investigated and the capacitance retention kept of 108% after 5000 cycles, which exhibited the excellent stability. Furthermore, the Ni/NiO-5 as the positive electrode and CNFs as negative electrode were assembled into the asymmetric supercapacitor (ASC) in 4 M KOH solution. The resulting Ni/NiO-5//CNFs device represented maximum energy density of 90.9 Wh kg−1 at the power density of 1350 W kg−1. Bifunctional materials could not only be utilized in catalytic field, but also be applied as electrode materials for the supercapacitor. This work offers a novel 3D needle-like structure for improving the potential of metal oxides for energy storage applications and this material also can be used as catalyst in Heck reaction, which displayed widely prospects applications as bifunctional materials.

Dissolved organic matter released from biochar (biochar-derived DOM, BDOM) could dominate the environmental behavior and fate of trace metals by forming BDOM-metal complexes. Here general, heterospectral as well as moving-window (MW) two-dimensional correlation spectroscopy (2DCOS) analyses of synchronous fluorescence and Fourier transform infrared spectra were employed to explore the heterogeneous binding characteristics between sludge BDOM and Cu(II). The results revealed that Cu-BDOM binding first occurred in the fulvic-like (368-380 nm), then humic-like (428 nm) fluorescent fractions, followed by infrared groups of phenolic hydroxyl groups, carboxylate, COH of polysaccharide groups, CC of aromatic carbon, CH of aliphatics and COC of aliphatic ethers. The binding affinity of the hydrophilic groups was stronger than that of hydrophobic groups in BDOM towards Cu(II). Fluorescence components in BDOM played a decisive role in the binding of Cu(II) with trace concentration (1 μM), while infrared functional groups made a substantial contribution in the complexation of Cu(II) with higher concentration (10-100 μM). The concentration of final configuration transformation point (11.7 μmol/mg in this study) by MW2DCOS analysis was suggested as an actual binding threshold that was helpful for evaluating their environmental behaviors.

Enhancing the activity of Co‐based electrocatalysts can be generally achieved by increasing the active center conductivity even fabricating hybrid materials for oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) process. Herein, we developed a bifunctional oxygen electrocatalyst for Zn-air batteries (ZABs). The Ce-doped Co3O4 nanoparticles embedded on carbon nanofibers complex catalyst (Ce@Co3O4/CNFs) was synthesized via the incorporation of the electrospinning technology and in-situ growth process. The Ce@Co3O4/CNFs exhibited the comparable performance to Pt/C and RuO2 in the alkaline environment with a half-wave potential of 0.810 V and overpotential of 380 mV(@ 10 mA cm-2) for the ORR and OER, respectively. Moreover, an all-solid-state rechargeable ZABs with Ce@Co3O4/CNFs cathode was also assembled, which shows a relatively narrow discharge-charge voltage gap and a good cycle performance. These results provide a novel approach in developing Co-based dual functional electrocatalysts to enable the energy applications.

Membrane separation is a simple and efficient technology for waste water treatment. However, organic pollutants such as antibiotics in complex water environment are hard to remove by the physical separation process. The coupling of photocatalysis and membrane separation can effectively remove the oil pollutants, meanwhile degrade the antibiotics. In this work, a composite membrane (BiOCl/TiO2@PAN) was prepared by the electrospinning technology and solvothermal process. The membrane showed an excellent superhydrophilicity in air and an underwater superoleophobicity, thus it could separate a series of oil in water emulsions with a high permeability (231-613 L m-2 h-1) without extra energy supply. Moreover, due to the photoresponse ability of BiOCl and TiO2, the membrane could effectively degrade a variety of antibiotics including the typical antibiotic tetracycline, chlortetracycline, oxytetracycline and demeclocycline within 30 minutes under full-spectrum and visible light irradiation. Eight-cycle repeating experiments showed that composite membrane had an excellent stability and an efficiency in photocatalytic reaction and oil-water emulsion separation. Photo-responsive composite membrane prepared in this study showed a broad application prospect in treatment of complex sewage where oily waste and antibiotics simultaneously exist.

Through a simple fiber template method, we combined the n-type TiO2 catalysts with n-type ZnS@ZnO heterojunction to synthesize a high-efficiency ternary hollow TiO2-ZnS@ZnO n-n heterojunction. Under these modified conditions, the composite catalysts could broaden the visible light absorption range of the pure TiO2, and both the hollow structure and heterojunction could inhibit the recombination ability of the photon-generated carriers. Optical and Electrochemical characterizations indicated that the photogenerated electrons and holes can be separated efficiently and the composites have visible light absorption. The experimental results show that, the removal efficiency of the optimal composites for photocatalytic degradation of Tetracycline Hydrochloride (TC) under visible light (λ ≥ 420 nm) was 86.67% due to the ·O2− free radicals of efficient production, it exhibited 5 times higher degradation rate towards Tetracycline Hydrochloride (TC) than pure TiO2. The composites with high photocatalytic activity could also effectively degrade Methylthionine Chloride (MB), Xylenol Orange (XO), Acid Red 18 and Rhodamine B (RhB) under the driving of visible light. This work provided a simple method to construct ternary heterojunction, and also provided a promising strategy to solve the environmental pollution problem in the future.

To improve the interfacial contact of PdO and CexOy, a novel nanotube PdO/CexOy with coaxial structure was designed and synthesized through combining electrospinning with carbonization. The structure and component of the composites were characterized using FT-IR, XRD, XPS, BET, TGA, TEM, FE-SEM, EIS and ICP techniques. The catalytic performance of ligand-free PdO-CexOy composite nanocatalyst was evaluated for Suzuki coupling reaction, and it exhibited excellent catalytic activity under mild aerobic conditions without using toxic solvents and inert protective atmosphere, achieving green catalysis.

Carbon nanofibers composite catalyst (Cu/CNFs) were developed by homogeneous polymeric solution based electrospinning and high temperature carbonization process in situ. The newly developed catalyst was thoroughly characterized through a series of characterization methods. The catalyst was carried out Ullmann coupling of N-heterocyclic compounds, N-arylationreaction and a wide range of aryl halides, and the catalyst performed excellent catalytic activity, selectivity and recyclability.

In this work, a novel highly efficient visible-light-driven AgI-BiOI/PAN composites was successfully synthesized and characterized by several tools. Based on the results of XRD, SEM and TEM of the AgI-BiOI/PAN composites, we could concluded that AgI nanoparticles and BiOI nanoparticles had been formed successfully on the PAN nanofibers. Compared with AgI/PAN and BiOI/PAN, AgI-BiOI/PAN showed highest photocatalytic performances and photochemical stability in degrading RhB, which is believed to be related to the larger number of surface active sites and faster spatial charge transfer between AgI and BiOI. The photocatalytic degradation efficiencies of AgI-BiOI/PAN after 210 min light irradiation was 98.5%. Meanwhile, the degradations of RhB by AgI-BiOI/PAN remained at 98.2% after six recycling runs. The application of PAN nanofibers made it easy to separate the catalysts from an aqueous solution without any loss. The degradation experiments of RhB in the presence of different scavengers suggested that h+ and O2− were the main reactive species. According to the experimental and characterization results, one plausible mechanism for enhanced RhB performance over AgI-BiOI/PAN composites was proposed.

In this work, a new, multifunctional heterojunction Au-CeO 2 -TiO 2 /CNFs was constructed through the some methods including electrostatic spinning, high-temperature calcination, solvothermal, impregnation and gas reduction, and it was applied in the selective oxidation of benzyl alcohol under heating and optical radiation in which it shows a certain catalytic activity (the conversation was 50% and 40% respectively). It implements the functionalization and concept of green chemistry, offering a new idea for the material preparation and its application.

It is urgent to design efficient photocatalysts for wastewater treatment due to the increasing severity of water pollution and the superiority of photocatalytic technology. In this work, a novel BiOI–BiOCl/NFs composite photocatalyst was prepared via electrospinning and one-pot solvothermal method. The BiOI–BiOCl nanosheets with cross-flake arrays were evenly grown on the PAN fiber. The as-prepared ICl-31 sample could degrade 98.7% RhB within 60 min and 82.1% TC within 120 min visible-light irradiation, the RhB degradation efficiency was 7.61 and 4.19 times than that of individual BiOCl and BiOI samples respectively, and the TC degradation efficiency was 2.7 and 1.89 times than that of corresponding samples, respectively. Meanwhile the prepared samples have great cycle stability. The improvement of photocatalytic performance should be ascribed to the organic combine of PAN nanofibers carrier and the construction of BiOI–BiOCl heterojunction. The direct Z-scheme migration mechanism was proved by trapping experiments. An internal electric field will be formed when the interface of BiOI and BiOCl are in contact. The internal electric field will expedite the transfer rate and separation efficiency of photogenerated carriers, therefore the photocatalytic efficiency was improved significantly.

Titanium dioxide (TiO2) has enormous potential in photocatalysis, but it was only active in the ultraviolet region and charge carriers rapidly recombined by it, so the improvement research on TiO2 is needed. To overcome these defects, carbon-doped TiO2 ultrathin nanosheets was successfully developed through simple synthesis route of electrospinning-solvothermal-calcination with adjusting the amount of titanium source. The as-prepared material had superior photocatalytic activity, cycle stability and universality, which 89.1 % tetracycline was photodegraded within 120 min under visible-light irradiation (λ ≥ 420 nm). Benefiting from large surface area, carbon doping and ultrathin TiO2 nanosheets with quantum dimensions. Meanwhile, The material has greater adsorption of target pollutants, and the valence band of pure TiO2 is significantly negatively shifted, which expands the light absorption range and forms a way to shorten the charge transfer. In this study, supplies a workable carbon-doping strategy to enhance the photocatalytic performance of TiO2 was supplied, which can be outspread to the design of other photocatalysts.

Abatement of lead (Pb) contamination in soil via chemical immobilization can reduce potential risks but is influenced by soil organic matter. The aim of this study was to observe and understand the influence of organic matter on Pb immobilization by phosphate. For this purpose, humic acid (HA) was introduced into a counterdiffusion system to mimic ionic reactions of the mineralization processes between the pollutant (Pb) and amendment agent (phosphate) in soil system, and were characterized jointly by in situ optical microscopy and ex situ XRD, SEM, TEM, and LSCM. The results indicate that lead immobilization in the counterdiffusion system involves a time-dependent crystallization process and that supersaturation occurs at nearly central region of the reaction zone. Entrapped HA had influence on crystal growth and size, causing more fragmented crystal morphology with increasing HA content, which can be explained by HA wrapping of the nucleation products and subsequent inhibition of reactions and crystal growth, as indicated by TEM and LSCM images. Mineral conversion from secondary lead orthophosphates to pyromorphite implies the promotion of more stable minerals. This approach provides evidence for a more intuitive understanding of the effects of HA on the immobilization of lead by phosphates.

Glucose was dispersed in polyacrylonitrile (PAN) nanofibers to develop a novel supporter for reducing and anchoring Cu 0 by hydrothermal process. The newly developed catalyst was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS), and amorphous Cu 0 were obtained. The prepared Cu 0 nanocatalyst was investigated as a heterogeneous catalyst for N -arylation reaction of N -heterocyclic compounds and a wide range of aryl iodides including iodobenzene, electron-rich and electron-poor aryl iodides, which performed excellent catalytic activity.

In this work, the preparation of the palladium nanoparticles with carbon nanofibers (Pd NPs/CNFs) catalyst for the Suzuki reaction was described. In the process, palladium nanoparticles were formed in the reaction of palladium chloride and glucose. The Pd NPs/CNFs complex catalyst was prepared in subsequent calcination processes, a series of characterization revealed that the Pd NPs were well-dispersed on the surfaces of the carbon nanofibers or embedded in the carbon nanofibers. This catalyst showed high catalytic activity for the Suzuki reaction of aryl halide and aryl boronic acid in the ethanol/water (v/v = 4/3) solution, and the catalyst still had good stability after 10 cycles.

Binderless hierarchically porous 4A-zeolite has been successful produced through hydrothermal crystallization, in which silicon-aluminum sol binded to the carbon nanofibers (CNFs), that is to say, where the CNFs powder was coated during the crystallization 4A-zeolite. The mixing of silica-alumina sol and CNFs was only a simple physical mixing process. The samples of micropores-macroporous hierarchical 4A-zeolite (P-4A-zeolite) was analyzed by a series of characterization techniques, such as field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM), simultaneous thermal analysis (STA) and CO2 adsorption-desorption (BET and BJH), and so on. In addition, the adsorption test of silver nanoparticles was carried out. The characterization results indicated the presence of micropores and the formation of macroporous. At the same time, silver adsorption test proved that the prepared P-4A-zeolite had good adsorption performance and the catalytic performance of Ag/P-4A-zeolite was further investigated through the epoxidation of styrene. Keywords: Carbon nanofibers, Porous 4A-zeolite, Silver nanoparticles, Styrene epoxidation

Multichannel carbon nanofibers-based amorphous vanadium (VMCNFs) was fabricated via electrospinning technology and calcination process. The amorphous V2O5 were homogeneous dispersed in the carbon nanofibers with inner hollow channels. One-dimensional structure nanomaterials with a compound inner fistulous pore construction promote the electrochemical property due to the synergistic effect between the hollow inner channels and carbon nanofibers with amorphous vanadium. With changing the addition amount of PS acting as a porogen, the optimized VMCNFs-0.5, in which the molar ratio of VO(acac)2/styrene monomer (SM) was 0.5, exhibited a high specific capacitance of 739 F g−1 at 0.5 A g−1 and good cycling performance with 80.3% capacitance retention after 1500 cycles. Thus this novel method can provide an acceptable idea for practical applications in energy storage.

A composite catalyst that layered graphite carbon nitride (g-C 3 N 4 ) nanosheets adhered on electrospun carbon fibers (CFs) carrier was prepared, and this catalyst occupied the efficient photocatalytic activity. The carbon fiber was obtained through electrospinning technology and high-temperature calcination process. The layered g-C 3 N 4 nanosheets was derived through the direct heating and ultrasonic exfoliation. After that, the g-C 3 N 4 /CFs were successfully synthesized in the hydrothermal process. In the process of degradation, composites had the capacity of degradation to different organic dyes under the UV-light irradiation, meanwhile, catalyst had excellent capacity of adsorption and a certain recycling performance. Thus, g-C 3 N 4 /CFs catalyst has potential appliance value in the degradation of organic pollutants.