对比分析了山西北部部分矿区(平朔、朔州和大同)煤矸石的重金属元素含量,探讨了煤矸石的组成及重金属元素的赋存形态和迁移规律.结果表明:矿区煤矸石的化学组成存在一些差异,但还是以SiO2和Al2 O3为主要组成;矿区煤矸石的淋溶浸出液大都偏碱性,其煤矸石中重金属含量都较小,Cu含量较多,其余危害重金属元素含量较低,基本不具有浸出毒性;朔州地区的Cu和Pb含量较高,大同地区的Cu和Mn含量较高;大多数重金属元素的赋存形态以稳定的硅酸盐结合态为主,其次是可氧化态和还原态.针对分析结果,提出了相应的对策建议和利用途径.

本文采用水热合成法制备碘钨酸银/碳纳米管复合材料和碘钨酸银单一材料,并对其进行扫描电子显微镜、X-射线粉末衍射、红外光谱表征、紫外-可见光漫反射以及电化学性质的测试.初步探究其光催化性能,实验结果表明,碘钨酸银/碳纳米管复合材料的催化性能较好,其光催化降解亚甲基蓝在60分钟可达到85.4％.

综述了近年来单原子催化剂合成方法的研究进展以及在制备过程中提升催化剂活性所要解决的问题.重点介绍了单原子催化剂在质子交换燃料电池(PEMFC)和二氧化碳电化学还原反应(CO2 RR)中的应用.最后结合目前单原子催化剂的研究现状和挑战,展望了其发展前景,以期对进一步构筑具有特定结构和催化功能的单原子催化剂的实验及理论起到积极的促进作用.

In order to provide a theoretical basis for the preparation of electrode and the degradation of salicylic acid Ni - based Ag - Cu alloy electrodes were prepared by electrodeposition method, which was further applied in the degradation process of salicylic acid. The electrochemical properties of the Ni - based Ag - Cu alloy electrodes with different molar ratios of Ag - Cu were studied. Under the same plate spacing, plus voltage, electrolysis time, the effects of electrolyte concentration on the degradation rate of salicylic acid were explored and the electrochemical oxidation degradation and ultrasound - assisted electrochemical synergetic degradation rate were compared. Results showed that under the same temperature, current density, electrode materials and distance between the anode and the cathode, when nAg∶nCu in the electrodeposition solution was equal to 8∶2, the surface morphology of Ni - based Ag - Cu alloy electrode is good, and the degradation rate of salicylic acid was the highest. The most suitable Na2SO4 electrolyte concentration was 1.064 g/L. Under this condition, the degradation rate of salicylic acid was 98.01%, and the ultrasound - assisted electrochemical oxidation rate was 99.89%, indicating that the degradation rate of salicylic acid under the synergy effect was higher.

The first example of diiron azadithiolate clusters supported on carbon nanotubes (1-f-SWCNTs) was constructed via covalent attachment. This nanohybrid shows efficient electrocatalytic proton reduction with a TOF of 9444 s−1 in 0.2 N aqueous H2SO4.

As diiron subsite models of [FeFe]-hydrogenases with odt bridge, two new series of PNP-chelate or-bridge diiron oxadithiolate complexes Fe-2(mu-odt)(CO)(4){(Ph2P)(2)NR} (1-3 and 4-6) were prepared by selective substitutions of diiron hexacarbonyl complex Fe-2(mu-odt)(CO)(6) (A, odt = SCH2OCH2S) with different PNP ligands (PNP = (Ph2P)(2)NR, R = (CH2)(3)Me, (CH2)(3)NMe2 and (CH2)(3)Si(OEt)(3)). All the new model complexes have been fully characterized by elemental analysis, various spectroscopies, and particularly for 1 and 4-6 by X-ray crystallography. In order to investigate the influence of coordination modes (chelate vs. bridge) of PNP ligands on redox and electrocatalytic properties of diiron model complexes for proton reduction, the protonation and electrochemistry of 1 and 4 as a pair of repre-sentative counterparts are well studied and compared in the absence and presence of strong acid (CF3CO2H) and weak acid (CH3CO2H) as different proton sources by using in situ IR and NMR spectros-copies as well as cyclic voltammetry (CV). For example, the protonation studies have shown that i) with excess CF3CO2H, protonations of both 1 and 4 are able to form the respective hydride species 1(mu H)(+) and 4(mu H)(+), but in which the former is completely protonated whereas the latter is less reactive; and ii) with excess CH3CO2H, complex 1 is unactive yet counterpart 4 is partially protonated to afford species 4(mu H)(+). The electrochemical investigations have displayed that i) with CF3CO2H as a proton source, complex 1 has a very simliar turnover frequency (TOF) and a much lower overpotential for cataytic proton reduction to H-2 in comparison to 4; and ii) with CH3CO2H as a proton source, complex 1 shows a much greater TOF value and a closer overpotential for H-2 evolution in contrast to 4. (c) 2020 Elsevier Ltd. All rights reserved.

以石墨烯、4-(2-吡啶偶氮)-间二苯酚和氯钯酸为前驱体,通过电化学沉积法制备了钯/4-(2-吡啶偶氮)-间二苯酚/石墨烯复合电极,并利用循环伏安法在硫酸溶液中对该电极进行表征.随后将电极应用到对盐酸四环素的电催化中,分析了4-(2-吡啶偶氮)-间二苯酚/石墨烯电极、4-(2-吡啶偶氮)-间二苯酚/石墨烯聚合电极及钯/4-(2-吡啶偶氮)-间二苯酚/石墨烯聚合电极对盐酸四环素的电催化效果,同时研究了扫描速度和盐酸四环素浓度对电催化效果的影响.

We describe a facile method to synthesize a new type of catalyst by electrodepositing Ag nanocrystals (AgNCs) on the different polymer dyes, Poly (methylene blue) (PMB) or Poly (4-(2-Pyridylazo)-Resorcinol) (PAR) modified graphene carbon spheres (GS) hybrids. The self-assembled GS take dual advantages of carbon spheres and graphene. Carbon spheres acts as nano-spacers prevent the aggregation of graphene and guarantee the fast electron transfer of GS. Secondly, polymerized dyes used here are beneficial for AgNCs growing as a linker. The effects of dyes on the growth habits, morphologies and catalytic properties for AgNCs were investigated. A novel electrochemical nonenzymatic sensor for hydrogen peroxide (H2O2) detection is fabricated based on the Ag/Polymer dyes/GS ternary composites modified glass carbon electrode (GCE) for the first time. It was found that the proposed electrodes, especially for Ag/PMB/GS/GCE, displayed a peculiar electrocatalytic activity towards H2O2 reduction synergistically as compared to Ag/PAR/GS/GCE or Ag/GS/GCE alone. Ag/PMB/GS/GCE showed a linear response over the H2O2 concentration range of 0.5 to 1112 mu M. The detection limit and sensitivity is 0.15 mu M and 400 mu A mM(-1) cm(-2), respectively. These outstanding results enable the practical application of Ag/PMB/GS/GCE for the H2O2 tracking released from MCF-7 (human breast cancer cells) with satisfactory results. (C) 2018 Elsevier B.V. All rights reserved.

Bi2 O3 -TiO2 composite material has been prepared by means of even precipitation method using Ti ( SO4 ) 2 as precursors .The photo-catalytic activity of the catalyst was evaluated by method of catalytic degradation of rhodam inc -B. The effects of photo-catalytic activities of the composite material at different temperature , different amount of composite were investigated .With the calcining temperature increasing , the photo -catalytic activity is increased , and the best calcining temperature is 550℃.When the concentration of catalyst is 0.026g/10mL, the degradation rate reaches 90%for 20mg/L concentration of rhodam inc -B under ultraviolet irradiation after 100 min.The photo -catalytic degradation of rhodam inc-B meets first order kinetics equation .

Developing inexpensive and highly efficient non-precious-metal electrocatalysts has been proposed as a promising alternative to platinum-based catalysts for the hydrogen evolution reaction (HER). Herein, we report novel FeP NPs supported on inexpensive and available candle soot (FeP-CS) derived from Fe3O4-CS hybrid precursors obtained after a phosphidation reaction. As HER electrocatalysts, the FeP-CS hybrids exhibit high electrocatalytic ability for HER with a Tafel slope of 58 mV dec(-1), a low onset overpotential of 38 mV, a large exchange current density of 2.2 × 10(-1) mA cm(-2) and an overpotential of 112 mV to obtain a current of 10 mA cm(-2). The present work shows significant advance in designing and developing non-precious-metal electrocatalysts for hydrogen evolution reaction.

A facile two-step method was developed for a large-scale growth of hierarchical MnCo2O4.5 nanostructure modified MnOOH nanorods (MC hybrid materials) as an efficient catalyst for water treatment. The synthesis involved a one-step hydrothermal process to prepare MnOOH nanorods and subsequently a simple solution method using hydrothermally synthesized MnOOH nanorods as both the template and Mn source to obtain MnCo2O4.5/MnOOH (MC) hybrid materials. The as-prepared MC hybrid materials with hierarchical structures could provide more active sites for catalytic degradation of methylene blue. These results indicate that the designed MC hybrid materials exhibit a promising capability for the degradation of dyes.

Graphene-based sheets that possess a unique nanostructure and a variety of fascinating properties are appealing as promising nanoscale building blocks of new composites. Herein, we present a general and effective approach for the preparation of metal oxide-graphene (metal oxide-G, metal oxide = Fe3O4, ZnO and Cu2O) by in situ nucleation and growth of metal oxide on the surface of graphene in tetraethylene glycol (TEG) solution. TEG, a nontoxic and environmentally friendly agent, acts as both solvent and reductant. Furthermore, the Fe3O4-G was employed as a two dimensional support for loading noble metal nanoparticles (Au or Pt) to synthesize Au@Fe3O4-G and Pt@Fe3O4-G ternary hybrid materials. The as-obtained Au@Fe3O4-G exhibited excellent catalytic activity in the reduction of 4-nitrophenol by NaBH4, and the Pt@Fe3O4-G showed remarkable electrocatalytic performance for hydrazine oxidation. We believe that the hybrid catalysts fabricated by this simple, efficient method have great potential for applications in other fields, such as electrochemical energy storage, sensors, and so on.

Ultrathin, two-dimensional (2D) nanosheets of layered transition-metal chalcogenides are theoretically and technologically intriguing. However, it still remains a great challenge to synthesize ultrathin nanosheets because of the lack of an intrinsic driving force for the anisotropic growth of 2D superposed microstructures. Here we demonstrate, for the first time to our knowledge, the in situ synthesis of largescale ultrathin Sb2S3 nanosheets on graphene sheets (G) by solvothermal method in a water-ethylene glycol mixed solvent. Owing to the synergetic chemical coupling effects between G and Sb2S3, Sb2S3-G hybrid nanosheets exhibit high catalytic performance for the degradation of methylene blue in the presence of H2O2. Moreover, it was found that the resulting Sb2S3-G shows good electrocatalytic activity towards hydrazine oxidation. This work not only offers a low-cost and high performance alternative technology for synthesizing sheet-like Sb2S3, but also opens the door toward the fabrication of varying types of metal sulfide-graphene nanomaterials that will have wide applications in catalysis, environmental, and new energy fields.

A facile approach was proposed for the synthesis of hierarchical CoxFe3−xO4 (CF) nanocubes, using Prussian Blue (PB) as precursor. Then, an efficient and simple colorimetric biosensor for H2O2 and glucose was fabricated using CF nanocubes as peroxidase mimetic.

A reversible detection method for vancomycin was developed utilizing the cantilever array sensor functionalized by a designed peptide consisting of a cysteine (Cys-), a space linker (-Gly-Gly-Gly-Gly-) and a molecular recognition ligand (-L-Lys-D-Ala-D-Ala). It was found that the peptide space linker was necessary and important for the response of the cantilever array sensor. The sensing cantilevers in the array were functionalized with the peptide while the reference cantilevers were modified by 6-mercapto-1-hexanol (MCH) to eliminate the influence of environmental disturbances. The binding between vancomycin and the peptide induced a change of surface stresses in the sensing cantilevers resulting in a differential deflection between the sensing and reference cantilevers. The reciprocal of the differential deflection is linear with the reciprocal of vancomycin concentration within the range of 2 μM to 100 μM (R=0.993) at a detection limit of 0.2 μM (S/N=3). The reversible detection can be realized just by regenerating the sensing cantilevers with running buffer solution. Other antibiotics such as doxycycline, streptomycin, and kanamycin have negligible effect on the response of the sensor. The sensor can also be utilized for reversible detection of vancomycin in serum background, which clearly indicates the potential of the sensor for vancomycin detection in real biological samples.

A synthetic route to FeP-GS hybrid sheets that show good stability and high electrocatalytic activity for hydrogen evolution reaction is reported. The materials are prepared via thermal phosphidation of pre-synthesized Fe3O4-GS hybrid sheets.

A facile hydrothermal method combined with a post solution reaction is developed to synthesize interconnected three-dimension (3D) hierarchical Co3-xFexO4 ferrite (CF) on nickel foam. By controlling the experimental parameters, the structures of the products are tailored from nanoflowers to microflowers with different sized void interiors. The obtained 3D hierarchical flower-like CF are characterized by field emission scanning electron microscopy, X-ray diffraction, and inductively coupled plasma mass spectrometer analysis. The 3D hierarchical flower-like CF-nickel foam with the rational structural feature could be used as binder and conductive agent-free supercapacitor electrodes directly. Such integrated electrodes exhibit a high specific capacitance and well cycling stability when the chargedischarge current density is high. Remarkably, the 3D hierarchical CF microflowers exhibit specific capacitance values of 768 F g(-1) at a constant current density of 6 A g(-1). The CF microflowers also show high charge-discharge reversibility with an efficiency of 79.2% after 5000 cycles. (C) 2014 Elsevier Ltd. All rights reserved.

A facile simple hydrothermal method combined with a post-solution reaction is developed to grow interconnected three dimensional (3D) hierarchical Co-Al layered double hydroxides (LDHs) on reduced graphene oxide (rGO). The obtained 3D hierarchical rGO-LDHs are characterized by field emission scanning electron microscopy, X-ray diffraction, and X-ray photo-electron spectroscopy. As LDHs nanosheets directly grow on the surface of rGO via chemical covalent bonding, the rGO could provide facile electron transport paths in the electrode for the fast Faradaic reaction. Moreover, benefiting from the rational 3D hierarchical structural, the rGO-LDHs demonstrate excellent electrochemical properties with a combination of high charge storage capacitance, fast rate capability and stable cycling performance. Remarkably, the 3D hierarchical rGO-LDHs exhibit specific capacitance values of 599 F g(-1) at a constant current density of 4 A g(-1). The rGO-LDHs also show high charge-discharge reversibility with an efficiency of 92.4% after 5000 cycles.

A facile two step process was developed for the synthesis of porous Co3O4 nanorods-reduced graphene oxide (PCNG) hybrid materials based on the hydrothermal treatment cobalt acetate tetrahydrate and graphene oxide in a glycerol-water mixed solvent, followed by annealing the intermediate of reduced graphene oxide-supported Co(CO3)0.5(OH)·0.11H2O nanorods in a N2 atmosphere. The morphology and microstructure of the composites were examined by X-ray diffraction, X-ray photoelectron spectroscopy, transmission electron microscopy and Raman spectroscopy. It is shown that the obtained PCNG have intrinsic peroxidase-like activity. The PCNG are utilized for the catalytic degradation of methylene blue. The good catalytic performance of the composites could be attributed to the synergy between the functions of porous Co3O4 nanorods and reduced graphene oxide.