Fervent Hype behind Magnesium Batteries: An Open Call to Synthetic Chemists—Electrolytes and Cathodes Needed

Magnesium metal is a superior anode which has double the volumetric capacity of lithium metal and has a negative reduction potential of −2.37 V vs. the standard hydrogen electrode. A major benefit of magnesium is the apparent lack of dendrite formation during charging which is one of the crucial concerns of using a lithium metal anode. In this Review, we highlight the foremost research in the development of electrolytes and cathodes and discuss some of the significant challenges which must be overcome in realizing a practical magnesium battery.     

The study of phase,microstructure, and magnetocaloric properties in LaFe11.6*xSi1.4B0.1 alloys

The effect of Fe on the phase and magnetocaloric property of LaFe_11.6*xSi_1.4B_0.1 alloys with x = 1.0–1.4 have been studied. The results show that the excess of Fe will make the α-Fe phases increase, but the easy corrosion LaFeSi phase reduces in LaFe_11.6*xSi_1.4B_0.1 alloys. All LaFe_11.6*xSi_1.4B_0.1 alloys keep the first-order magnetic phase transition. The saturation magnetizations of LaFe_11.6*xSi_1.4B_0.1 alloys with x > 1 are much higher than LaFe_11.6Si_1.4B_0.1 alloy under 2T magnetic field. This results in the maximum isothermal magnetic entropy changes, and the relative cooling power of LaFe_11.6*xSi_1.4B_0.1 alloys is bigger than for LaFe_11.6Si_1.4B_0.1 alloys.     

Synthesis and Application of N-Tosyl Piperidinyl-Containing α-Aminophosphonates

Abstract

A series of novel (4′-tosyl) piperidin-4-yl containing α-aminophosphonates were synthesized by a one-pot reaction, efficiently catalyzed by magnesium perchlorate, under solvent-free conditions from 1-tosylpiperidin-4-one, substituted aromatic amines, and diethyl phosphite (DEP). The synthesized compounds were characterized by IR, ¹H NMR, ¹³C NMR, ³¹P NMR, and HRMS spectroscopy. A single-crystal X-ray structure of diethyl 4-(2-chlorophenyl) amino-1-(4’-methylbezenesulfonyl) piperidin-4-yl-phosphonate (2a) was obtained, and some of the title compounds displayed insecticidal activities against Plutella xylostella.

Supplementary materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfer, and Silicon and the Related Elements for the following free supplemental files: Additional figures and tables.     

Alternative Synthesis of A C,C-Diacetylenic Phosphaalkene

Abstract

Bis(trimethylsilyl)-terminated C,C-diacetylenic phosphaalkene was prepared from Mes*PCl₂ and a propargylic Grignard reagent that in turn was formed from 3-bromo-1,5-bis(trimethylsilyl)penta-1,4-diyne and Rieke-Mg.     

Solvent-Free Acetylation of Thiols Under Catalysis of MgBr2·OEt2

Solvent-free protection of aromatic and aliphatic thiols with acetic anhydride was performed at room temperature under trace quantities of magnesium bromide ethyl etherate, affording rapid formation of various thiol esters in excellent yields.     

REACTION OF SULFUR CHLORIDE WITH ACETOPHENONE. II

Abstract

In a previous paper,¹ we reported the formation of a resinous material (1) from the reaction of sulfur chloride with acetophenone which, upon treatment with DMF, yielded phenylglyoxylthiodimethylamide (4). We now report two additional resinous materials (5, 6), resulting from bromination of sodium phenacylthiosulfate (3) and diphenacyl disulfide (7) respectively, both of which not only resemble resinous 1 in appearance, but also yield 4 upon treatment with DMF in aqueous alkali.

Resinous 1, 5, and 6 appear to have the same common basic structure and differ only in the number of sulfur atoms bonded between the common units. Cleavage at the sulfur-sulfur bonds and elimination of hydrogen halide then yields identical oxothioamides from 1, 5, or 6. The latter appears to be a general reaction, and several oxothioamides were prepared by this synthetic method from 1, 5, and 6 and various amides and amines.     

Flammability and Thermal Oxidative Degradation Kinetics of Magnesium Hydroxide and Expandable Graphite Flame Retarded Polypropylene Composites

The flammability and the thermal oxidative degradation kinetics of expandable graphite (EG) with magnesium hydroxide (MH) in flame‐retardant polypropylene (PP) composites were studied by limiting oxygen index (LOI), UL‐94 test, and thermogravimetric analysis (TGA). The results show that EG is a good synergist for improving the flame retardancy of PP/MH composite and the effect is enhanced with decreasing EG particle size. The Kissinger method and Flynn‐Wall‐Ozawa method were used to determine the apparent activation energy (E) for degradation of PP and flame retarded PP composites. The data obtained from the TGA curve indicate that EG markedly increases the thermal degradation temperature of PP/MH composites and improves the thermal stability of the composites. The kinetic results show that the values of E for degradation of flame retarded PP composites is much higher than that of neat PP, especially PP/MH composites with suitable amount of EG, which indicates that the flame retardants used in this work have a great effect on the mechanisms of pyrolysis and combustion of PP.     

Tuning Nanoparticle Catalysis for the Oxygen Reduction Reaction

Advances in chemical syntheses have led to the formation of various kinds of nanoparticles (NPs) with more rational control of size, shape, composition, structure and catalysis. This review highlights recent efforts in the development of Pt and non‐Pt based NPs into advanced nanocatalysts for efficient oxygen reduction reaction (ORR) under fuel‐cell reaction conditions. It first outlines the shape controlled synthesis of Pt NPs and their shape‐dependent ORR. Then it summarizes the studies of alloy and core–shell NPs with controlled electronic (alloying) and strain (geometric) effects for tuning ORR catalysis. It further provides a brief overview of ORR catalytic enhancement with Pt‐based NPs supported on graphene and coated with an ionic liquid. The review finally introduces some non‐Pt NPs as a new generation of catalysts for ORR. The reported new syntheses with NP parameter‐tuning capability should pave the way for future development of highly efficient catalysts for applications in fuel cells, metal‐air batteries, and even in other important chemical reactions.     

Determination of zinc in marine/lacustrine sediments by graphite furnace atomic absorption spectrometry using Pd/Mg chemical modifier and slurry sampling

Effectiveness of Pd/Mg chemical modifier for the accurate direct determination of zinc in marine/lacustrine sediments by graphite furnace atomic absorption spectrometry (GF-AAS) using slurry samples was evaluated. A calibration curve prepared by aqueous zinc standard solution with addition of Pd/Mg chemical modifier is used to determine the zinc concentration in the sediment. The accuracy of the proposed method was confirmed using Certified Reference Materials, NMIJ CRM 7303-a (lacustrine sediment) from National Metrology Institute of Japan, National Institute of Advanced Industrial Science and Technology, Japan, and MESS-3 (marine sediment) and PACS-2 (marine sediment) from National Research Council, Canada. The analytical results obtained by employing Pd/Mg modifier are in good agreement with the certified values of all the reference sediment materials. Although for NRC MESS-3 an accurate determination of zinc is achieved even without the chemical modifier, the use of Pd/Mg chemical modifier is recommended as it leads to establishment of a reliable and accurate direct analytical method. One quantitative analysis takes less than 15 minutes after we obtain dried sediment samples, which is several tens of times faster than conventional analytical methods using acid digested sample solutions. The detection limits are 0.13?µg?g^?1 (213.9?nm) and 16?µg?g^?1 (307.6?nm), respectively, in sediment samples, when 40?mg of dried powdered samples are suspended in 20?mL of 0.1?mol?L^?1 nitric acid and a 10?µl portion of the slurry sample is measured. The precision of the proposed method is 8–15% (RSD).