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Owing to the adverse influences of irreversible oxidation, the development of MXene‐based materials, especially those with satisfactory performance and longevity for aqueous energy storage, continues to suffer severe challenges. Herein, the strategy of targeted passivation‐supported defect‐lock‐oxygen is conceived, whereby engineered the V2CTx material for controllable partial oxidation with enhanced regioselectivity. When the material works, inside the intrinsic defects, the outward diffusion of oxidation is confined by the Lewis bases around the defects, which allows for the controllable progress of oxidation. The defect‐locked oxygen oxidizes the exposed carbon, thus forming sufficient amorphous carbons for enhancing the capacitive‐type adsorption of K‐ions. Then the oxidized defects enabled the fast kinetics via the cross‐layer transport of K‐ions. Benefiting from the strategy, the electrode assembly V2CTx‐RTIL (V2CTx equipped with room temperature ionic liquid) exhibits high capacity, good rate capability, and ultra‐longevity compared with those of the MXene materials so far reported. This work presents the first strategy of targeted passivation‐supported defect‐lock‐oxygen for high‐rate capability and super long‐cycling aqueous K+ storage and hopefully would provide the inspiration for the future design of novel electrodes. [ABSTRACT FROM AUTHOR]

The etherification and amination of difluoroenol silyl ethers with benzoquinones and quinonediimines were achieved by using hexafluoroisopropanol (HFIP) as the solvent. This 1,6‐addition reaction could construct difluorooxymethyl and difluoroaminomethyl compounds under metal‐free conditions. It is preliminarily speculated that the reaction took place through a single electron transfer (SET) process. [ABSTRACT FROM AUTHOR]

Core–shell-like structured polymeric ionic liquid hybrid nanoreactors with "internal hydrophobic–external hydrophilic" characteristics were successfully synthesized through the Stöber method and reversible addition–fragmentation chain transfer (RAFT) polymerization. Firstly, we introduced hydrophobic organosilicon as an inner core and fixed Pd nanoparticles (∼0.69 mmol g−1) in the pore and finally constructed a hydrophilic shell, which not only ensured the dispersity of the catalyst in water but also effectively prevented the leaching of Pd species. The structure and properties of nMIE@Pd/SiNP-CPDB were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), N2 adsorption–desorption, ICP-OES, thermogravimetric analysis (TGA) and ultraviolet and visible spectrophotometry (UV-vis) characterization methods. The adsorption enthalpy of the best catalyst for styrene was calculated using the Clausius–Clapeyron equation and the value was −12.765 kJ mol−1, which strongly verified that the prepared catalyst could effectively promote mass transfer and the adsorption of reactants or products. Furthermore, the as-prepared nanoreactors exhibit distinguished catalytic activity for aqueous hydrogenation reactions and even after 7 cycles, the catalysts still maintain their superior catalytic activity, showing almost no leaching of palladium species. [ABSTRACT FROM AUTHOR]

Green sustainable production is very important for the development of human society and the environment. In this study, Pickering interfacial catalysts (Pd-p(xTEMPA-yFDABCO-zDVB)@Fe3O4) with a CO2 and magnetic double response were prepared by a template-free method for the first time. The introduction of terminal alkene modified Fe3O4@SiO2 and 2,2,6,6-tetramethyl-4-piperidyl methacrylate (TEMPA), a CO2 responsive functional group, not only improved the formation of the mesoporous structure and increased the specific surface area of the final catalyst but also accelerated the demulsification rate of the emulsion, which was beneficial to the separation of products and the recovery of catalysts. The application of the Pd-p(xTEMPA-yFDABCO-zDVB)@Fe3O4 in hydrogenation resulted in an excellent conversion (88–99%) at room temperature and atmospheric pressure. The double basic catalyst p(xTEMPA-y[FDABCO][OH]-zDVB)@Fe3O4, exploited as a catalyst for the transesterification of soybean oil with ethanol, was obtained by exchanging Br− and OH−. These excellent performances are mainly due to the "microreactor" droplets formed by the Pickering emulsion and the mesoporous channels provided by the magnetic mesoporous poly(ionic liquid)s. On the other hand, the double responsive Pickering interfacial catalysts can be recycled at least 5 times without significant degradation in catalytic activity. [ABSTRACT FROM AUTHOR]

Microsized carbon spheres with the refined interior structure are highly desired, while it is challenging to achieve controllability limited to synthetic strategy. Herein, a novel architectural approach is proposed for developing interior multi-chamber carbon microspheres (MCMs) with the help of a liquid template. We focus on building "rooms" in fruit wine yeast and yielding "fungi house," which apply to other kinds of yeast. The size and number of the "room" can be controlled. To the best of our knowledge, such biomass-derived carbon spheres with defined interior structures have never been reported yet. When used as electrodes for supercapacitors and capacitive deionization, the exemplified MCM exhibits specific capacitance 339.31 F g−1 at 0.5 A g−1 and a salt adsorption capacity of 21.61 mg g−1 at 1.2 V, as well as excellent rate performance and cycle stability. Given the structure-dependent property, the architectural approach broadens the avenue to develop advanced materials. [ABSTRACT FROM AUTHOR]

Supercapacitors are highly attractive in the large-scale energy storage field, but the "trade-off" between the gravimetric capacitance and the volume and area specific capacitance greatly affects their further development. In this work, we developed coralloid-like porous carbon sheets (CPCS) with double support structure via a bidirectional anchoring strategy, exhibiting ultra-low specific surface area (26.95 m2 g−1) and moderate packing density (0.75 g cm−3). In the meantime, the proposed dual-anchor structure model made the interior "self-doping" defects and the exterior "foreign-doping" defects fully exposed, which is seldom obtained by other artificial methods. Based on this, it delivered a superior overall performance in gravimetric, volumetric, and areal capacitances (308.89 F g−1, 231.67 F cm−3, and 1146 μF cm−2) and stable cyclability (10 000 cycles), which is the highest capacitance reported for polyacrylonitrile-based hard carbon without chemical/physical activation. Considering the low-energy and innovative synthesis route, our work may shed some light on developing advanced carbons promising for supercapacitors. [ABSTRACT FROM AUTHOR]

A magnetic nanoparticles-supported chiral aminocyclohexane in combination with sulfamide, which was modified by an imidazolium ionic moiety, was prepared and characterized by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), vibrating sample magnetometry (VSM), thermal gravimetric (TG) analysis and elementary analysis. The catalyst was successfully applied not only in the enantioselective Michael addition but also in the asymmetric aldol condensation to afford good to excellent yields (70-94%) and satisfactory stereoselectivity ( ee: 92-100%, dr: 91:9-99:1).The role of the ionic moiety was verified by comparison of the catalyst with an ionic moiety-free counterpart. The heterogeneous catalyst was easily separated and recovered using external magnetic force and can be used for up to five times without obvious loss in its catalytic activity. [ABSTRACT FROM AUTHOR]

Ionic tagged propyl amine immobilized on magnetic nanoparticles (MNPs) was synthesized and fully characterized. The novel catalyst (MNPs@PA-IL) was applied in phospha-Michael addition and gave the desired β-phosphonomalonates in good yields. The MNPs supported catalyst with ionic tag could be readily recovered from the reaction mixture using an external magnet. Compared with ionic-free counterpart (MNPs@PA), MNPs@PA-IL present better catalytic activity. The proposed mechanism regarding the MNPs@PA-IL catalyzed phospha-Michael reaction was also discussed. Graphical Abstract: [Figure not available: see fulltext.] [ABSTRACT FROM AUTHOR]

In acidic solution, complex micelles were formed by diblock copolymers of poly (ethylene glycol)- b-poly (ε-caprolactone) (PEG- b-PCL) and folate-poly (2-(dimethylamino) ethyl methylacrylate)- b-poly (ε-caprolactone) (Fol-PDMAEMA- b-PCL) with a PCL core, a mixed PEG/Fol-PDMAEMA shell. The surface charge of the complex micelles was positive at acidic surroundings for the protonated PDMAEMA. With increasing pH value to 7.4 (above p K of PDMAEMA), these micelles could convert into a core-shell-corona (CSC) structure composing a hydrophobic PCL core, a collapsed PDMAEMA shell, and a soluble PEG corona. Compared to core-shell micelles formed by PEG- b-PCL, micelles with CSC structure can prolong degradation by enzyme. Doxorubicin was physically loaded into the PCL core. The drug release rate was pH-dependent. At pH 5.5, complex micelles with core-shell structure showed faster drug release rate, while at pH 7.4, complex micelles gained CSC structure which control the drug release at a lower rate. The multifunctional complex micelles were prepared for enhanced tumor therapy. [ABSTRACT FROM AUTHOR]

Knoevenagel condensation of aromatic aldehydes with active methylene compounds such as malononitrile, ethylcyanoacetate, benzimidazol-2-acetonitrile and benzothiazole-2-acetonitrile proceeded very smoothly, catalyzed by nano-Fe3O4 encapsulated-silica particles supported primary amine. Both reaction time and yield are satisfying. The advantages of this catalyst are ease of preparation, non-toxicity, low cost, ease of handling and recyclability. [ABSTRACT FROM AUTHOR]

Thermo-responsive polymeric micelles of poly (ethylene glycol)- b-poly(2-hydroxyethyl methacrylate- g-lactide)- b-poly( N-isopropylacrylamide) (PEG-P(HEMA-PLA)-PNIPAM) with core-shell-corona structure were fabricated for applications in controlled drug release. The graft copolymer of PEG-P(HEMA-PLA)-PNIPAM was self-assembled into core-shell micelles with a densely PLA core and mixed PEG/PNIPAM shells at 25 °C in aqueous media. By increasing the temperature above the lower critical solution temperature of PNIPAM, these core-shell micelles could be converted into core-shell-corona micelles because of the collapse of PNIPAM block on the PLA core as the inner shell and the soluble PEG block stretching outside as the outer corona. Anticancer drug doxorubicin (DOX) was loaded in the polymeric micelles as a model drug. Compared with polymeric micelles formed by liner PEG- b-PLA- b-PNIPAM triblock copolymer, these polymeric micelles exhibited higher loading capacity, and release of DOX from the polymeric micelles with core-shell-corona structure was well-controlled. [ABSTRACT FROM AUTHOR]

Glycerol was used as a reaction medium as well as promoter for aza-Michael addition of aromatic amines to electronic deficient α,β-unsaturated ketones. Various aromatic amines can react smoothly with chalcone, 2-cyclohexen-1-one, 2-cyclopenten-1-one, and ethyl vinyl ketone to achieve good to excellent yields in the absence of any catalyst. [ABSTRACT FROM AUTHOR]

An efficient and facile protocol for aza-Michael addition of aliphatic and aromatic amines to electron-deficit alkenes using [TMG][Lac] as catalyst under solvent-free conditions was established. [ABSTRACT FROM AUTHOR]

Knoevenagel condensation of aromatic aldehydes with active methylene compounds such as malononitrile, ethylcyanoacetate, and cyanoacetamide proceeded very smoothly in reusable and cheap ionic liquid 2-hydroxyethylammonium formate at room temperature in the absence of a catalyst. Compared to other reported ionic liquids, the ionic liquid 2-hydroxyethylammonium formate shows better potential in the applications on the industrial scale with its low cost and viscosity. [ABSTRACT FROM AUTHOR]

A new separation method, wiped molecular distillation (WMD), was applied and experimental work was carried out to study the effect of operation parameters such as distillation temperature, pressure, feed flow rate, wiped speed and the separation stages on purifying the raw material containing 95% 3-hydroxypropionitrile (HPN). It was an excellent result that the mass concentration of HPN in the final product can be more than 99.5% under the optimistic operation conditions. The high purity cannot be achieved with normal separating method including rectification and extraction in practice. As for the raw material, a function of HPN purity in distillate was plotted with distillation temperature and pressure in experiment ranges. According to the experiment data obtained and the theory in molecular distillation, the distillation speed of HPN and separation efficiency were computed. It was concluded that the distillation speed of HPN and the separation efficiency were satisfying for industrial production. [ABSTRACT FROM AUTHOR]

The Knoevenagel condensation of aromatic aldehydes with active methylene compounds such as malononitrile, ethyl cyanoacetate, benzimidazole-2-acetonitrile and benzothiazole-2-acetonitrile proceeded very smoothly, in a reusable and cheap choline chloride and urea based deep eutectic solvents. Both reaction time and yield are satisfactory. The advantages of this catalyst are that it is readily available, biodegradable, non-toxic, low cost and is recyclable. [ABSTRACT FROM AUTHOR]