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The ceramic membrane is widely used in the field of domestic sewage treatment due to its high flexural strength, acid and alkali corrosion resistance, easy cleaning, and other advantages. This article uses coal gangue and loess as the main raw material (coal gangue:loess = 8:2), calcium carbonate as the pore‐forming agent, and carboxymethyl cellulose as the binder. The ceramic membrane was prepared by extrusion molding method and solid particle sintering method. The effects of pore‐forming agent content and sintering temperature on the physical and chemical properties of the ceramic membrane, such as flexural strength, microstructure, pure water flux, and acid‐base corrosion rate, were investigated. The results show that when the sintering temperature is 1000°C and the pore‐forming agent content is 10wt%, the pure water flux exceeds 1434L/h m2 MPa, the flexural strength exceeds 25.4 MPa, the porosity exceeds 46.9%, and the acid‐alkali corrosion rate of the ceramic membrane below 1.6%/0.15%. At this time, the treatment efficiency of domestic sewage is excellent, the removal rate of COD, suspended solids and ammonia nitrogen exceeds 27.66%, 99.9%, and 26.77%, respectively. This work has trend‐setting significance for the fabrication and application of low‐cost ceramic membranes. [ABSTRACT FROM AUTHOR]

Methanol steam reforming (MSR) provides an alternative way for efficient production and safe transportation of hydrogen but requires harsh conditions and complicated purification processes. In this work, an efficient electrochemical‐assisted MSR reaction for pure H2 production at lower temperature (~140 °C) is developed by coupling the electrocatalysis reaction into the MSR in a polymer electrolyte membrane electrolysis reactor. By electrochemically assisted, the two critical steps including the methanol dehydrogenation and water‐gas shift reaction are accelerated, which is attributed to decreasing the methanol dehydrogenation energy and promoting the dissociation of H2O to OH* by the applied potential. Furthermore, the reduced H2 partial pressure by the hydrogen oxidation and reduction process further promotes MSR. The combination of these advantages not only efficiently decreases the MSR temperature but also achieves the high rate of hydrogen production of 505 mmol H2 g Pt−1 h−1 with exceptionally high H2 selectivity (99 %) at 180 °C and a low voltage (0.4 V), and the productivity is about 30‐fold than that of traditional MSR. This study opens up a new avenue to design novel electrolysis cells for hydrogen production. [ABSTRACT FROM AUTHOR]

High‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) are crucial in future energy systems. However, the activity and stability of the electrocatalysts are severely restricted by high temperature and phosphoric acid poisoning. Herein, PtCe alloy as oxygen reduction reaction (ORR) electrocatalyst for HT‐PEMFCs exhibits fantastic performance. Ce can increase the electronic density of Pt, weakening phosphoric acid poisoning and improving ORR activity. The optimized electronic structure can also reduce the dipole effect between Pt and O, which suppresses the irreversible oxidation of Pt. Additionally, the dramatically negative heat of formation in PtCe catalyst brings high kinetic barrier of metal diffusion and dissolution. With this electrocatalyst, the HT‐PEMFCs show a preeminent peak power of 605 mW cm−2 with 0.3 mgPt cm−2. After 30000 cycles of accelerated stability test, the peak power density only decreases by 31.6%, achieving the goal of Department of Energy in 2020 (<40% loss). [ABSTRACT FROM AUTHOR]

The durability degradation during stack‐operating conditions seriously deteriorates the lifetime and performance of the fuel cell. To alleviate the rapid potential rise and performance degradation, an anode design is proposed to match the working temperature of high‐temperature proton exchange membrane fuel cells (HT‐PEMFCs) with the release temperature of hydrogen from palladium. The result is significantly enhanced hydrogen oxidation reaction (HOR) activity of Pd and superior performance of the Pd anode. Furthermore, Pd as hydrogen buffer and oxygen absorbent layer in the anode can provide additional in situ hydrogen and absorb infiltrated oxygen during local fuel starvation to maintain HOR and suppress reverse‐current degradation. Compared with the traditional Pt/C anode, the Pd/C also greatly improved HT‐PEMFCs durability during start‐up/shut‐down and current mutation. The storage/release of hydrogen provides innovative guidance for improving the durability of PEMFCs. [ABSTRACT FROM AUTHOR]

Pd and Pd xNi nanoparticles have been supported on reduced graphene oxide (Pd/ rGO and Pd xNi/ rGO) by using the microwave-assisted heating method in glycol. The morphology, composition and electrochemical performance have been characterized by TEM, XRD, XPS and electrochemical methods. The XRD and XPS results show that there are no PdNi alloy particles formed in Pd xNi/ rGO and the composites exist mostly in the form of Pd0 and NiOOH species. The electrochemical results reveal that Pd xNi/ rGO synthesized from the feeding source of Pd and Ni with an atomic ratio of 4∶1 exhibits higher activity, better stability and smaller electron transfer resistance toward formic acid electro-oxidation compared with commercial Pd/C, Pd/ rGO and other Pd xNi/ rGO samples. The excellent electrocatalytic performance indicates that the addition of appropriate amount of Ni can greatly enhance the activity and stability of Pd catalysts for formic acid oxidation. [ABSTRACT FROM AUTHOR]

Cornstalk core, a renewable by-product of agriculture, has been used as a carbon precursor to prepare high-performance electrode materials used in electrochemical capacitors (ECs). The influences of temperature and the ratio of activator (KOH) to carbon ( mKOH/ mC) on the structures of porous carbon materials (PCMs) derived from cornstalk core have been investigated systematically. The PCM obtained at optimal conditions ( mKOH/ mC=6, activated at 800 °C) exhibits a porous structure with a large specific surface area of 2139 m2 g−1 and total pore volume of 1.16 cm3 g−1. Acting as an electrode material, the optimum PCM exhibits excellent capacitive performance with a specific capacitance of 317.0 F g−1 at a scan rate of 1 mV s−1. More promising, a high power density of 28.3 kW kg−1 and energy density of 6.8 Wh kg−1 are achieved in 6 mol L−1 KOH aqueous electrolyte, as well as high-rate capability and excellent cycling stability. The capacitor has a time constant of about 0.3 s, and could retain more than 93 % of its initial capacitance after 10 000 cyclic processes. This work proposes a potential biomass resource to produce effective porous carbons for high-performance ECs. [ABSTRACT FROM AUTHOR]

An environmentally friendly approach is presented to synthesize sulfonated reduced graphene oxide (S-rGO) by using L-ascorbic acid ( L-AA) and aryl diazonium salt of sulfanilic acid. The preparation conditions have been optimized in order to obtain isolated and conductive S-rGO, and the products have been characterized by Ultraviolet-Visible spectroscopy, Fourier transformed infrared spectroscopy, Raman, X-ray photoelectron spectroscopy and X-ray powder diffraction and electrochemical methods. The results show that the S-rGO sheets possess excellent water-solubility and high electrical conductivity, which implies that the oxygen-containing functional groups have been removed and conjugated sp2 network has been restored. What's more, the electrochemical measurements reveal that the capacitive performance of the S-rGO has been improved compared with the graphene oxide (GO) and the reduced graphene oxide (rGO, reduced by L-AA). The optimum S-rGO exhibits a specific capacitance of 205 F·g−1 and good cycling stability (3.9% decreasing after 10000 cycles), which are better than those for graphene oxide (109 F·g−1 and decreasing 6.6% after 10000 cycles) and rGO (139 F·g−1 and decreasing 11.3% after 10000 cycling). This approach proves a new route to improve the capacitive properties of rGO. [ABSTRACT FROM AUTHOR]

This work reports a sensitive amperometric biosensor for organophosphate pesticides (OPs) fabricated through modifying glassy carbon electrode with acetylcholinesterase (AChE) immobilized on graphene/polyaniline (G/PANI) composite film. The obtained G/PANI composite films show large specific area, high conductivity, good biocompatibility, and fast redox properties and have perfect layered and encapsulated structures. The as-prepared biosensor shows high affinity to acetylthiocholine (ATCl) with a Michaelis-Menten constant value of 0.20 mmol/L. Furthermore, based on the inhibition of the enzymatic activity (immobilized AChE) caused by the model compound of carbaryl (one kind of pesticides), it is found that the inhibition activity of carbaryl is proportional to its concentration ranging from 38 to 194 ng·mL−1. The developed biosensor shows a detection limit of 20 ng·mL−1 ( S/ N=3) for OPs detection and exhibits good performance such as good reproducibility and acceptable stability, which makes it possible to provide a new and promising tool for the analysis of enzyme inhibitors. [ABSTRACT FROM AUTHOR]

The hydrogels of reduced graphene oxide (rGOHGs) have been synthesized through treating GO with various concentrations of sodium hypophosphite (NaH2PO2) under hydrothermal condition. The results reveal that the structure of rGOHGs changes along with the increase of the concentration of NaH2PO2. The rGO sheets prepared with low concentration of NaH2PO2 exhibit more crimples and larger specific surface area than those prepared with high concentration of NaH2PO2. The measurements of the capacitive performances of rGOHGs reveal that the rGOHGs prepared with low concentration of NaH2PO2 possess larger specific capacitance ( Cs) than that prepared with high concentration of NaH2PO2 at low cyclic voltammetry scan rates. However, the rGOHGs prepared with high concentration of NaH2PO2 possess larger Cs at high scan rates, more stability and better high-rate capability than those prepared at low concentration. It is believed that the structures and properties of rGOHGs can be adjusted by controlling the concentration of NaH2PO2 according to the requirement. [ABSTRACT FROM AUTHOR]

ABSTRACT The carbon nanotubes (CNTs) have been loaded on the melamine foam (MF) to form the composite (CNTs/MF) by dip-dry process, then polypyrrole (PPy) is coated on CNTs/MF (PPy/CNTs/MF) through chemical oxidation polymerization by using FeCl3·6H2O adsorbed on CNTs/MF as oxidant to polymerize the pyrrole vapor. Finally, CNTs are coated on the surface of PPy/CNTs/MF to increase the conductivity of the composite (CNTs/PPy/CNTs/MF) by dip-dry process again. The composites have been characterized by X-ray diffraction spectroscopy, scanning electron microscopy and electrochemical method. The results show that the structure of the composites has obvious influence on their capacitive properties. According to the galvanostatic charge/discharge test, the specific capacitance of CNTs/PPy/CNTs/MF is about 184 F g−1 based on the total mass of the composite and 262 F g−1 based on the mass of PPy (70.2 wt % in the composite) at the current density of 0.4 A g−1, which is higher than that of PPy/CNTs/MF (120 F g−1 based on the total mass of the composite and 167 F g−1 based on the mass of the PPy). Furthermore, the capacitor assembled by CNTs/PPy/CNTs/MF shows excellent cyclic stability. The capacitance of the cell assembled by CNTs/PPy/CNTs/MF retains 96.3% over 450 scan cycles at scan rate of 20 mV s−1, which is larger than that assembled by CNTs/PPy/MF (72.5%). © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 39779. [ABSTRACT FROM AUTHOR]