Atomic structures and electronic properties of different contact surfaces for C F -SiO triboelectric nanogenerator based on first-principles investigations.

Modification of the dielectric friction layer materials is an ideal way to enhance the output performance of a triboelectric nanogenerator (TENG), but current research mostly focuses on the metal-polymer or metal-SiO materials. In this work, we constructed different TENG models based on polymer C F -SiO electret materials, and the electronic properties of the different contact surfaces were investigated using first principles. We found that the charge transfer in C F -SiO materials occurred only at the contact interface, and it was partially affected by the terminal atoms near the SiO interface.

Efficient adsorptive removal of potassium from potassium perrhenate solution using a cationic ion exchange resin.

Potassium is a harmful impurity in the rhenium sinter, which adversely affects its mechanical properties by significantly reducing the density of sintered rhenium. Cationic resin is a promising material for potassium removal. In this study, the strong acid cationic exchange resin C160H was pretreated with an HNO solution to enhance its performance in potassium removal.

Influence of alkali metal ions (K and Na) on the preparation of magnesium hydroxide hexagonal flakes.

Magnesium hydroxide (Mg(OH)), as a green halogen-free flame retardant, has attracted significant attention in the field of flame retardant composite materials. In addition to conventional indicators such as purity and whiteness, Mg(OH) is required to take the form of regular hexagonal sheets to ensure the dispersion of composite materials. We use irregular large particles of Mg(OH) prepared by the magnesium factory in western Qinghai as raw materials to study the influence of alkali metal ions K and Na mainly present in salt lakes on the physicochemical properties of Mg(OH).

Catalytic upgrading of volatiles in co-pyrolysis of coal and biomass by Mo-MFI molecular sieves.

Catalytic co-pyrolysis of coal and biomass can improve both solid waste utilization and high value-added product content to obtain higher quality oils, which is significant for the clean and efficient use of coal and the expansion of biomass resource utilization. This study focuses on improving the quality of tar and the content of light fractions by catalytic reforming of coal and biomass co-pyrolysis volatiles. Molybdenum-doped MFI-type molecular sieve catalysts (Mo-MFI) were successfully prepared by a hydrothermal method using TPAOH as a structure-directing agent.

Extraction of alumina and silica from high-silica bauxite by sintering with sodium carbonate followed by two-step leaching with water and sulfuric acid.

Efficient utilization of high-silica bauxite and minimization of bauxite residue are of great significance for the sustainable development of the alumina industry. In this paper, a novel process is proposed to extract AlO and SiO from high-silica bauxite without residue discharge, that is, sintering bauxite with NaCO followed by two-step leaching with water and sulfuric acid. The effects of the sintering parameters on the process were investigated, and the phase transformations during sintering and leaching were revealed by using phase diagram, thermogravimetric analysis (TGA) and differential scanning calorimetric (DSC), X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive spectrometer (EDS) methods.

Regulated synthesis of Zr-metal-organic frameworks with variable hole size and its influence on the performance of novel MOF-based heterogeneous amino acid-thiourea catalysts.

We present an efficient and easy synthesis method for incorporating organocatalytic moieties into Zr-metal organic frameworks (Zr-MOFs). The catalytic activity and selectivity of the new chiral catalysts were improved by adjusting the aperture of the MOF cavities. The hole size of the Zr-MOF was modulated by adding acid and replacing bridge ligands during synthesis.

Synergetic effect of photocatalysis and peroxymonosulfate activated by MFeO (M = Co, Mn, or Zn) for enhanced photocatalytic activity under visible light irradiation.

Nanosized MFeO (M = Co, Mn, or Zn) photocatalysts were synthesized a simple sol-gel method. MFeO photocatalysts exhibited lower photocatalytic activity for the degradation of levofloxacin hydrochloride under visible light irradiation. For enhancement of photocatalytic activity, MFeO was used to activate peroxymonosulfate and degrade levofloxacin hydrochloride under visible light irradiation.

Controllable synthesis of N-doped carbon nanohorns: tip from closed to half-closed, used as efficient electrocatalysts for oxygen evolution reaction.

The development of efficient, cost-effective and stable N-doped carbon material with catalytic activity as an excellent catalyst for the oxygen evolution reaction (OER) is critical for renewable energy systems. In this study, the unique tip-half-closed N-doped carbon nanohorns (THC-N-CNHs) were firstly produced by the positive pressure-assisted arc discharge method using N as the nitrogen source. Benefitting from the novel tip-half-closed structure and sufficient porosity, the specific surface area (SSA) of THC-N-CNHs is calculated to be 670 m g without any further treatment, which is three times larger than that of traditional tip-closed CNHs.

Optimized nano-metal particles filled into carbon nanohorns to achieve high N-doping amount and high porosity for enhanced oxygen evolution reaction.

Nano-metal-filled N-doped carbon materials have been actively verified as promising alternatives for precious-metal catalysts in the oxygen evolution reaction (OER). Herein, Ni/Fe/Cu-filled N-doped carbon nanohorns (CNHs) are synthesized a positive pressure assisted arc discharge method using a Ni/Fe/Cu rod charged in an anode hole in a N and Ar mixture. We first found that the amount of N atom doping can be controlled by the types of nano-metal particles encapsulated by CNHs.

Mesoporous adsorbent for competitive adsorption of fluoride ions in zinc sulfate solution.

Al-La hybrid gel was constructed using an innovative acid-catalyzed and calcination free sol-gel formation process which only included a sol-gel process lasting for 30 min and a drying procedure at 150 °C. This novel material was used as an adsorbent for competitive adsorption of fluoride ions in zinc sulfate solution. The properties, optimal adsorption conditions, synthetic principle and adsorption mechanism of the material were systemically investigated.

The differential proliferation of AOB and NOB during natural nitrifier cultivation and acclimation with raw sewage as seed sludge.

Nitrifier immigration from sewers to wastewater treatment systems is attracting increasing attention for understanding nitrifier community assembly mechanisms, and improving process modeling and operation. In this study, nitrifiers in raw sewage were cultivated and acclimated in a sequencing batch reactor (SBR) for 90 days to investigate the characteristics of the influent nitrifiers after immigration. During the experiment, specific nitrite utilization rate (SNUR) exceeded specific ammonia utilization rate (SAUR) when floc size reached 224 ± 46 μm, and nitrogen loss occurred at the same time.

Novel recyclable BiOBr/FeO/RGO composites with remarkable visible-light photocatalytic activity.

Magnetic BiOBr/FeO/RGO composites with remarkable photocatalytic capability were prepared by a simple hydrothermal method to load 3D flower-like microspherical BiOBr onto the surface of FeO/RGO. Under visible-light irradiation ( > 420 nm), the BiOBr/FeO/RGO composite with 56% mass percentage of FeO/RGO shows the optimal removal ability for Rhodamine B, and the total removal efficiency is 96%. The coupling of FeO/RGO and BiOBr elevates the conduction band of BiOBr, which enhances the reduction level of BiOBr/FeO/RGO composites.

Application of MoS in the cathode of lithium sulfur batteries.

Molybdenum disulfide (MoS) with a two-dimensional layered structure can effectively inhibit the shuttle effect of lithium-sulfur batteries (Li-S batteries). It contains metal-sulfur bonds and combines with polysulfides through electrostatic bonds or chemical bonds. In this paper, the structure and properties of MoS are briefly introduced, and the research progress on the design, preparation, structure and properties of MoS as a cathode material for Li-S batteries in recent years is reviewed.

Organic loading rate shock impact on extracellular polymeric substances and physicochemical characteristics of nitrifying sludge treating high-strength ammonia wastewater under unsteady-state conditions.

Laboratory experimentation was used to investigate the impact of the organic loading rate shock on extracellular polymeric substances (EPSs) and the physicochemical characteristics of nitrifying sludge (NS) treating high-strength ammonia wastewater. The increased organic loading rates (OLRs) strongly influenced the stability of the NS with regard to nutrient removal, biomass-liquid separation, and surface properties, leading to the sludge system collapse at the OLR of 0.75 kg COD per kg MLVSS d.

Phosphate adsorption onto thermally dehydrated aluminate cement granules.

Phosphorus is the main element for eutrophication of water bodies. Aluminate cement is a cheap building material rich in aluminium and calcium which have significant effects on phosphate adsorption. This study aimed at the investigation of removal behavior of phosphate by thermally dehydrated aluminate cement granules, treated at different temperatures, and the adsorption mechanisms.