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This paper proposed a new method for the determination of chlorine in coal by Eschka's mixture decomposition-ion chromatography so as to satisfy the needs of determining chlorine content in coal samples in large batches in coal exploration, coal production and processing industries.Specifically, this paper improved the sample pretreatment steps and determined the experimental parameters.The detection limit of the method was 0.001 7 %, the relative standard deviations of ten parallel determinations of three actual coal samples were in the range of 1.08 % ~3.92 %, the recoveries of six spiked determinations were in the range of 98 % ~104 %, and the results of the three standard coal samples were all within the guaranteed values.Results showed that the detection limit of the method was lower than that of the national standard method, and the precision and accuracy met or exceeded the national standard method.The determination of chlorine in coal by Eschka's mixture decomposition-ion chromatography has the advantages of simple operation, low cost and high determination efficiency and could be widely applied in the batch determination of a large number of samples.

Rechargeable Zn–air batteries (ZABs) are considered highly competitive technologies for meeting the energy demands of the next generation, whether for energy storage or portable power. However, their practical application is hindered by critical challenges such as low voltage, CO2 poisoning at the cathode, low power density, and poor charging efficiency Herein, a rechargeable hybrid alkali/acid Zn–air battery (h‐RZAB) that effectively separates the discharge process in an acidic environment from the charging process in an alkaline environment, utilizing oxygen reduction reaction (ORR) and glycerol oxidation reaction (GOR) respectively is reported. Compared to previously reported ZABs, this proof‐of‐concept device demonstrates impressive performance, exhibiting a high power density of 562.7 mW cm−2 and a high operating voltage during discharging. Moreover, the battery requires a significantly reduced charging voltage due to the concurrent utilization of biomass‐derived glycerol, resulting in practical and cost‐effective advantages. The decoupled system offers great flexibility for intermittently generated renewable power sources and presents cost advantages over traditional ZABs. As a result, this technology holds significant promise in opening avenues for the future development of renewable energy‐compatible electrochemical devices. [ABSTRACT FROM AUTHOR]

In this study, we used effective and one-pot Heck coupling reactions under moderate reaction conditions to construct two new hybrid porous polymers (named OVS-P-TPA and OVS-P-F HPPs) with high yield, based on silsesquioxane cage nanoparticles through the reaction of octavinylsilsesquioxane (OVS) with different brominated pyrene (P-Br4), triphenylamine (TPA-Br3), and fluorene (F-Br2) as co-monomer units. The successful syntheses of both OVS-HPPs were tested using various instruments, such as X-ray photoelectron (XPS), solid-state 13C NMR, and Fourier transform infrared spectroscopy (FTIR) analyses. All spectroscopic data confirmed the successful incorporation and linkage of P, TPA, and F units into the POSS cage in order to form porous OVS-HPP materials. In addition, the thermogravimetric analysis (TGA) and N2 adsorption analyses revealed the thermal stabilities of OVS-P-F HPP (Td10 = 444 °C; char yield: 79 wt%), with a significant specific surface area of 375 m2 g–1 and a large pore volume of 0.69 cm3 g–1. According to electrochemical three-electrode performance, the OVS-P-F HPP precursor displayed superior capacitances of 292 F g−1 with a capacity retention of 99.8% compared to OVS-P-TPA HPP material. Interestingly, the OVS-P-TPA HPP showed a promising HER value of 701.9 µmol g−1 h−1, which is more than 12 times higher than that of OVS-P-F HPP (56.6 µmol g−1 h−1), based on photocatalytic experimental results. [ABSTRACT FROM AUTHOR]

Sodium-based dual-ion batteries have received increased attention owing to their appealing cell voltage (i.e., >3 V) and cost-effective features. However, the development of high-performance anode materials is one of the key elements for exploiting this electrochemical energy storage system at practical levels. Here, we report a source-template synthetic strategy for fabricating a variety of nanowire-in-nanotube MSxTey@C (M = Mo, W, Re) structures with an in situ-grown carbon film coating, termed as nanocables. Among the various materials prepared, the MoS1.5Te0.5@C nanocables are investigated as negative electrode active material in combination with expanded graphite at the positive electrode and NaPF6-based non-aqueous electrolyte solutions for dual-ion storage in coin cell configuration. As a result, the dual-ion lab-scale cells demonstrate a prolonged cycling lifespan with 97% capacity retention over 1500 cycles and a reversible capacity of about 101 mAh g−1 at specific capacities (based on the mass of the anode) of 1.0 A g−1 and 5.0 A g−1, respectively. Sodium-based dual-ion batteries are promising electrochemical energy storage devices. Here, the authors report a source-template synthetic strategy to prepare carbon-coated MoS1.5Te0.5 nanocables and their use as anode active materials in Na-based dual ion cells. [ABSTRACT FROM AUTHOR]

Sodium‐tellurium (Na‐Te) battery, thanks to high theoretical capacity and abundant sodium source, has been envisaged as one promising battery technology, its practical application yet faces daunting challenges regarding how to mitigate the critical issues of uncontrollable dendrites growth at Na anode and polytellurides shuttling effect at Te cathode. We here report an elaborative design for fabrication of microsphere skeleton nanohybrids with three‐dimensional (3D) hierarchical porous carbon loading CeO2 quantum dots (CeO2‐QDs/HPC), which feature highly favorable properties of sodiophilic and catalysis for hosting sodium and tellurium, respectively. The systematic investigations coupling with first‐principle calculations demonstrate the CeO2‐QDs/HPC not only offers favorable structure and abundant electrocatalytic sites for facilitating interconversion between Te and NaxTe as a cathode host, but also can function as dendrite inhibitor anode host for reversible sodium electro‐plating/deposition. Such Na‐Te battery exhibits admiring electrochemical performance with an impressive specific capacity of 392 mAh g−1, a long cycling stability over 1000 cycles, as well as remarkably high energy density of 192 Wh kg−1 based on the total mass of anode and cathode. Such proof‐of‐concept bifunctional host design for active electrode materials can render a new insight and direction to the development of high‐performance Na‐Te batteries. [ABSTRACT FROM AUTHOR]