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The degradation of cellulosic ethanol wastewater by peroxymonosulfate (PMS) is one of the important methods to solve the environmental problems caused by it. In order to improve the degradation efficiency of cellulosic ethanol wastewater, the design of more catalytically active and stable chalcogenide catalysts has become a problem that needs to be solved nowadays. The application of foreign cations to replace the A- or B-site to increase the oxygen vacancy of the chalcocite catalyst to improve the efficiency of chalcocite catalytic degradation of wastewater has received much attention. In this work, the perovskite material LaCuO3 was synthesized using a citric acid-sol–gel method, and the novel material La1-xSrxCuO3 was prepared by doping of Sr element at the A position. In order to prepare catalytic materials with better performance, this study carried out performance-optimized degradation experiments on the prepared materials and determined that the catalytic efficiency of La0.5Sr0.5CuO3 prepared under the conditions of the complexing agent dosage of 1:2, the gel temperature of 80 °C, and the calcination temperature of 700 °C was better than that of the catalytic materials prepared under other conditions. The prepared material has good recycling function; after four times recycling, the removal rate of pollutant COD is still more than 85%. This work provides a new synthesis method of perovskite material with good recycling function and high catalytic efficiency for the degradation technology of cellulosic ethanol wastewater. [ABSTRACT FROM AUTHOR]

A Mg and Cl co-doped Li3V2(PO4)3/C (LVMPCl/C) material has been synthesized via a solid state method. The effects of Mg and Cl co-doping on the electrochemical properties, structure and morphology of Li3V2(PO4)3 are investigated. Detailed analysis of the XRD patterns suggests that Mg and Cl atoms partly occupy V and O sites in the crystal structure of Li3V2(PO4)3, respectively. The valence states of Mg and Cl elements are investigated using X-ray photoelectron spectroscopy (XPS). Combining XRD patterns with 31P NMR spectra, it is further demonstrated that doped Mg and Cl atoms affect the local electronic structure of P atoms in Li3V2(PO4)3. According to the results of electrochemical performance, LVMPCl/C exhibits excellent discharge capacity as high as 129.1 mA h g−1 at 0.1C. In addition, the capacity retention of LVMPCl/C is almost 100% after 100 cycles at 3.0–4.3 V. Impedance spectroscopy (EIS) and cyclic voltammetry (CV) curves illustrate the lower charge transfer resistance and much more decreased polarization of LVMPCl/C than the pristine one. The excellent electrochemical performance of LVMPCl/C can be attributed to its larger Li ion diffusion channels, which is ascribed to the increased unit-cell volumes, smaller particle sizes and higher electronic conductivity. [ABSTRACT FROM AUTHOR]

Poor electronic conductivity and "shuttle effect" as well as large volume change during cycling hinder the further practical applications of lithium-sulfur batteries (LSBs). Here, N,O dual-doped carbons were developed as sulfur host with adjustable porosity, graphited degree and surficial chemistry by simply changing molten inorganic salts (none, NaCl, NaCl/FeCl 3) during sintering with aniline-pyrrole copolymer. NaCl promotes the graphitization and porosity with multi-scaled porous carbon host (CH2). NaCl/FeCl 3 boosts doping content and facilitates transformation of both chemical state of doping elements and morphology to micro-meso pores dominated nanosheet (CH3) from little porous bulk (CH1). The flexible CH3 nanosheet with micro-mesopores could physically block dissolved Li 2 S n (4 ≤ n ≤ 8) and provide large interfacial area to guarantee good electronic conductivity and ionic transport of the sulfur cathode for improving the electrochemical reactions kinetics. Furthermore, the high content doped pyrrolic N and epoxidized O in CH3 enhance chemical adsorption of soluble Li 2 S n and accelerate the conversion process between Li 2 S n and Li 2 S 2 /Li 2 S. Hence, CH3/S system exhibits ∼30% and ∼167% higher capacity than CH2/S and CH1/S after 200 cycles at 0.2 C. Our results clarify the working mechanism of carbon morphology and nitrogen, oxygen co-doping state tuning and promote the development of high-electrochemical performance LSBs. [Display omitted] [ABSTRACT FROM AUTHOR]