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Entirely oligosaccharide-based supramolecular amphiphiles were constructed via host–guest interactions between ferrocene-terminated acetylated-maltoheptaose (Fc-AcMH) and β-cyclodextrin-terminated four-arm star maltoheptaose (MH4-β-CD). The amphiphiles could self-assemble to form spherical supramolecular nanoparticles to provide efficient drug delivery platforms. The combination of a pH-sensitive covalent acetal group and the oxidation-sensitive noncovalent host–guest interaction of β-CD and ferrocene provided the obtained fully oligosaccharide-based supramolecular amphiphiles. The structures of these amphiphiles could respond to the intracellular microenvironment. [ABSTRACT FROM AUTHOR]

Electrochemical CO2 reduction (ECR) to valuable chemicals and fuels using renewable energy is a promising way to reduce carbon emission. Herein, Sn-based films were electrodeposited on Ag foil surfaces (Sn/Ag-y) for selective ECR to CO, where y represented the concentration of SnCl2 in the electrodeposition bath. The Sn/Ag-20 electrode achieved a high CO faradaic efficiency of 96.0% with a current density of 69.3 mA cm−2. The enhanced catalytic performance could be attributed to appropriate superficial properties, large electrochemical active surface areas, low charge transfer resistance, efficient stabilization capacity of the CO2˙− intermediates, and suitable combination with electrolytes. [ABSTRACT FROM AUTHOR]

Hole transport materials (HTMs) have an important impact on the improvement of perovskite solar cell (PSC) performance. So far, HTMs with symmetrical and unbiased molecular structures have been extensively studied. Azulene, which is composed of a seven-membered ring and a five-membered ring, has shown nice potential in organic field-effect transistors and organic photovoltaic cells. In this research, we synthesized four bias structured HTMs (Azu-diT, Azu-diF, Azu-2T6F and Azu-2F6T) based on 2,6-substituted azulene. Among them, the more bias structured HTMs showed better electronic properties, and peripheral substitution on the 6-position of azulene had a greater influence on the solubility and film formation property. After being applied in PSCs, a power conversion efficiency (PCE) up to 16.16% was obtained by Azu-2T6F. These results demonstrate the potential of azulene derivatives as a hole transport material and the impact of biased peripheral regulation. [ABSTRACT FROM AUTHOR]

Atomic-level structure engineering has proven indispensable for fast ion transport kinetics. Herein, a unique framework of NiSe/Ni heterostructure with abundant heterointerface encapsulated hollow carbon spheres, namely NiSe/Ni@C, is synthesized as an anode for SIBs. The NiSe/Ni@C electrode delivers enhanced Na+ storage performance in terms of high specific capacity (490 mA h g−1) and excellent rate capability (546 mA h g−1) at a current of 5.0 A g−1 over 2000 cycles. This study can provide in-depth insights into the interface effect in hybrid structures and shed light on designing energy storage materials. [ABSTRACT FROM AUTHOR]

Deep eutectic solvents (DESs) have been intensively investigated as promising “green” solvents for a range of industrial processes, although most research continues to be focused on binary DESs. This paper reports on a class of ternary DESs formed by choline chloride (ChCl), polyethylene glycol (PEG), and boric acid (BA) that may be viewed as a new system for extraction and oxidative desulfurization (ODS) of diesel fuel. Compared with organic acid-based DESs, ternary DESs offer advantages including low volatility, low toxicity, and high activity. After tuning the molar ratio of the three compositions, sulfur removal reached 99.2% in 2 h at 60 °C when the molar ratio of H2O2 to dibenzothiophene was 6. The binary DESs, ChCl/PEG and ChCl/BA, showed unsatisfactory extraction and oxidation efficiency. The reaction mechanism identified through experimental and theoretical methods showed that superoxide radical may be the main active oxygen species, and BA-based peroxides may also play an important role. The results of this study may expand the use of BA and supply a new class of DESs for ODS and other possible applications. [ABSTRACT FROM AUTHOR]

FexOy@FexOy/C nanoparticles with a soap-bubble-like shell have been synthesized, and the materials exhibit excellent Fenton catalytic performance. More importantly, FexOy@FexOy/C nanoparticles as catalysts and precursors could catalyze organic dye molecules to form iron oxide@organic dye polymer core–shell nanospheres. [ABSTRACT FROM AUTHOR]

Five low-cost deep eutectic solvents (DESs) were synthesized based on choline chloride (ChCl) and a series of straight-chain monobasic acids. Under UV light irradiation, one-pot extraction combined with the metal-free photochemical aerobic oxidative deep desulfurization of fuels in deep eutectic solvents was successfully achieved. This liquid-liquid extraction and photochemical oxidative desulfurization system (EPODS) comprised of air, isobutylaldehyde (IBA), DESs and model oil. The factors influencing sulfur removal were systematically investigated, including the amount of DES, volume ratio of model oil and IBA, different sulfur concentrations, different substrates and fuel composition. The sulfur removal of dibenzothiphene (DBT) could reach 98.6% with air as oxidizing agent under UV light irradiation. Sulfur removal by different sulfur compounds decreased as BT ＞ DBT ＞ 4,6-DMDBT. The possible photochemical oxidative desulfurization mechanism was researched by gas chromatograph-mass spectrometer (GC-MS), electron spin-resonance (ESR) spectroscopy and density functional theory (DFT). [ABSTRACT FROM AUTHOR]

Metal-free graphene-like boron nitride (BN) samples were prepared and applied as adsorbents for removing dibenzothiophene (DBT) in model oil. The results showed that the graphene-like BN exhibited a remarkable adsorption performance. The adsorption capacity could reach 28.17 mg S g−1 adsorbent. Experiments have been carried out to investigate the effects of the number of BN layers, DBT initial concentration, and temperature on DBT adsorption. Langmuir and Freundlich isotherm models were used to study the adsorption of DBT on BN. The kinetic results showed that the adsorption process was best described by the pseudo-second-order kinetic model. Density functional theory (DFT) was employed to prove that the Lewis acid–base interaction plays an important role in removing DBT over graphene-like BN. [ABSTRACT FROM AUTHOR]

The multi-step reaction of CO2 over basic catalysts significantly improves the diversity of products, vividly embodying the ability of green chemistry to turn waste into treasure. However, under a Lewis acidic CO2 atmosphere, the activity maintenance of the multi-step reaction puts forward higher requirements for the reversible regeneration ability of the basic catalysts. Novel Lewis–Brønsted binary basic poly(ionic liquid)s (LB-PILs) were successfully developed through a radical copolymerization followed by ion-exchange strategy, and were applied to the two-step synthesis of dimethyl carbonate (DMC) by coupling CO2 cycloaddition and CH3OH transesterification without any cocatalyst. Relying on the activation of CO2 by Lewis basic tertiary N and the thermal recovery of nucleophilic HCO3− to stronger Brønsted basic OH− with the help of temperature control in CH3OH transesterification, the LB-PILs presented high activity, stable repeatability and linear carbonate universality. In situ IR analysis and Knoevenagel condensation, combined with theoretical calculations, provided reliable support for the ingenious incorporation of reversible regeneration of basic catalysts in a Lewis acidic CO2 atmosphere and multi-step coupling reaction process of CO2. [ABSTRACT FROM AUTHOR]

With the rapid development of lithium-ion batteries (LIBs), the selective recovery of lithium and other valuable metals from spent LIBs is in urgent need because of the shortage of Li and valuable metals along with the toxicity of components. Herein, a tandem leaching system for the selective recovery of Li and other valuable metals (Co, Mn) from spent LIBs was engineered by employing formic acid and its derived deep eutectic solvent (DES) as leaching agents. Results illustrate that Li can be selectively leached by formic acid, and other valuable metals can be recycled by DES. The selective leaching of valuable metals from different types of LIBs were investigated, and it was found that the tandem leaching system was applicable to the different types of LIBs with recovery efficiencies >99% for valuable metals at leaching temperatures as low as 70 °C. This finding may provide an environmentally friendly and effective approach for the selective recovery of Li and other valuable metals from spent LIBs. [ABSTRACT FROM AUTHOR]

A series of WO3/TiO2 catalysts with a pore structure were successfully synthesized. The catalysts were systematically characterized and it was found that different calcination temperatures had great effects on the pore structure of the catalysts. The catalyst presented a mesoporous structure after calcining at 550 °C (expressed as 550-WO3/TiO2) and had the largest specific surface area among the mesoporous catalysts. The oxidation of dibenzothiophene (DBT) with 550-WO3/TiO2 catalyst reached 100% under optimum conditions. After recycling for 6 times, the oxidation of DBT could still achieve a DBT removal of 96.7%, suggesting that the catalyst had good stability and recycle performance. In addition, DBT sulfone (DBTO2) was proven to be the only oxidation product of DBT after the reaction, as observed by the GC-MS analysis. The catalytic activities of the catalyst on different substrates were also investigated, and the activities decreased in the order: DBT ＞ 4-MDBT ＞ 4,6-DMDBT ＞ BT. [ABSTRACT FROM AUTHOR]