Micrometer scaled MoS2 hierarchical hollow cubic cages assembled by bilayers can be synthesized via a one-step self-assembly coupled with intermediate crystal templating process without any surfactant, in which the intermediate K2NaMoO3F3 crystal formed in-situ and then served as the self-sacrificed template based on the Kirkendall Effect; The MoS2 hierarchical hollow cubic cages were employed for electrochemical hydrogen storage with a high capacity of 375 mAh g(-1) due to the more active edges exposing on the upright-standing nanoplates.

No abstract

Two homologous series of double-tail hybrid surfactants containing a hydrocarbon chain and a fluorocarbon chain attached to the same hydrophilic head group have been synthesized. The micellar solutions of such hybrid surfactants have been studied by conductance, surface tension, 19F NMR and 'H NMR. The dependence of the cmc on the chain length follows Klcven's equation. The micellar aggregation numbers are 10-35 and become smaller as the chain length increases. When the hydrocarbon chain bears three carbons or more, both the fluorocarbon and the hydrocarbon chains are incorporated inside the micelle. IntroductionThere has been a continuous effort in industry to prepare new formulations of detergents by changing the compositions of the surfactants, builders, and additives. However, there is relatively little development in the synthesis and characterization of new surfactants that have unusual structures, properties, and applications. The hybrid surfactants described in this paper represent part of our effort in this direction. They are composed of a hydrocarbon (HC) chain and a fluorocarbon (FC) chain attached to the same hydrophilic head group and are a new category of compounds which have not been explored previously.Doubletail surfactants with two HC chains attached to a sulfate head group have been studied by Winsorl and Evans2 in the 1950s. These homologous compounds of sodium dialkyl sulfate have the structural formulae RR'CHOS03Na, in which R and R' are unbranched HC chains with R having a longer chain length than R'. The hybrid surfactants reported here have similar structures, except that one of the chains is an unbranched FC chain.It has long been noticed that fluorinated surfactants are particularly efficient in lowering surface tension. Normally, in the mixture of a FC surfactant with a suitable HC surfactant, the FC surfactant reduces the surface tension while the HC surfactant aids in the reduction of the interfacial tension. The net result can be a system that easily wets and spreads on otherwise hard-tewet ~urfaces.~ However, for ionic surfactants with the same headgroup charge, the application of this advantage of combined effect is limited because of the demixing of HC/FC mixed surfactants. To overcome this problem, some single-chain surfactants containing a FC segment and a HC segment were synthesized, and they show good wettability on solid substrates containing FC ~omponents.~ Recently, Abenin and Cambon reported the synthesis of a series of double-tail HC/FC surfactants R&&NHCH2CHOHCH2NRI "Rm5 Such surfactants are very effective in lowering the surface tension or interfacial ten~ion.~ To our knowledge, hybrid surfactants containing separate FC and HC chains attached to the same head group have not been reported. In the present work, the synthesis, characterization, and the micellar properties of a homologous series of novel double-tail hybrid surfactant are described:

Many organophosphorus (OP) based compounds are highly toxic and powerful inhibitors of cholinesterases that generate serious environmental and human health concerns. Organothiophosphates with a thiophosphoryl (P=S) functional group constitute a broad class of these widely used pesticides. They are related to the more reactive phosphoryl (P=O) organophosphates, which include very lethal nerve agents and chemical warfare agents, such as, VX, Soman and Sarin. Unfortunately, widespread and frequent commercial use of OP-based compounds in agricultural lands has resulted in their presence as residues in crops, livestock, and poultry products and also led to their migration into aquifers. Thus, the design of new sensors with improved analyte selectivity and sensitivity is of paramount importance in this area. Herein, we review recent advances in the development of fluorescent chemosensors for toxic OP pesticides and related compounds. We also discuss challenges and progress towards the design of future chemosensors with dual modes for signal transduction.