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The emission of NH 3 into atmosphere is seriously harmful for human health and public safety, thus the capture and recovery of NH 3 from ammonia emissions is highly desirable. In recent years, many kinds of solid adsorbents have been exploited to absorb NH 3 . However, these materials do not show the advantages of high uptake capacity and good recyclability at the same time. Here, nontoxic and low cost few-layer BiI 3 nanosheets have been prepared from bulk BiI 3 powder by a simple and efficient liquid phase exfoliation strategy using green solvents and then applied for the NH 3 capture for the first time. The results show that the adsorption capacity of NH 3 of BiI 3 nanosheets reaches up to 22.6 mmol/g at 1.0 bar and 25 °C, which approaches the record value for NH 3 adsorption. Importantly, the NH 3 uptake in BiI 3 nanosheets is completely reversible and no clear loss in uptake capacity is observed after 10 cycles of adsorption-desorption. Furthermore, the BiI 3 nanosheets exhibit remarkable selectivity for the separation of NH 3 /CO 2 at 70 °C with theoretical selectivity coefficient of 700, which is promising for the selective separation of NH 3 and CO 2 in hot tail gas of some industrial processes. Mechanism studies indicate that such superior NH 3 capacity, excellent reversibility and remarkable selectivity are primarily attributed to the Bi 3+ -NH 3 coordination interactions.

In recent years, metal-organic frameworks (MOFs) have been explored as emulsifiers for the fabrication of Pickering emulsions and then used for hybrid material synthesis and interface catalysis. Nevertheless, stimuli-responsive Pickering emulsions stabilized by MOFs have been rarely reported so far, although they are of great importance for fundamental research studies and practical applications. Herein, for the first time, triethylenetetramine (TETA)-functionalized MOFs (ZIF-90/TETA) have been designed, synthesized, and used for fabricating CO 2 -/N 2 -response Pickering emulsions. It is shown that even at the ZIF-90/TETA content of 0.25 wt %, the functional MOF can still efficiently emulsify n -hexane and water to form a high internal phase Pickering emulsion. Importantly, the Pickering emulsion can be easily and reversibly switched between emulsification and demulsification by bubbling of CO 2 and N 2 alternatively at atmospheric pressure. The possible mechanism of the CO 2 /N 2 switchable emulsion is investigated by zeta potential, water contact angle, interfacial tension, 13 C NMR spectroscopy, and an optical microscope. It is found that the acid-base reaction of CO 2 with TETA anchored on the surface of ZIF-90 leads to the production of hydrophilic ammonium bicarbonate and carbamate, which results in the emulsification of the Pickering emulsion. However, when N 2 is bubbled to remove CO 2 , the reverse reaction takes place to cause the demulsification of the Pickering emulsion. Moreover, the CO 2 /N 2 switchable Pickering emulsion has been successfully used as a microreactor for Knoevenagel reactions to demonstrate a highly efficient integration of chemical reaction, product separation, and ZIF-90/TETA recycling for a sustainable chemical process.

The nanoplasmonic metal-driven photocatalytic activity depends heavily on the spacing between metal nanoparticles (NPs) and semiconductors, and this work shows that ethylene glycol (EG) is an ideal candidate for interface spacer. Controlling the synthetic systems at pH 3, the composite of Ag NPs with EG-stabilized amorphous TiO 2 (Ag/TiO 2 -3) was synthesized by the facile light-induced reduction. It is verified that EG spacers can set up suitable geometric arrangement in the composite: the twin hydroxyls act as stabilizers to bind Ag NPs and TiO 2 together and the nonconductive alkyl chains consisting only of two CH 2 are able to separate the two building blocks completely and also provide the shortest channels for an efficient transfer of radiation energies to reach TiO 2 . Employed as photocatalysts in hydrogen evolution under visible light, amorphous TiO 2 hardly exhibits the catalytic activity due to high defect density, whereas Ag/TiO 2 -3 represents a remarkably high catalytic efficiency. The enhancement mechanism of the reaction rate is proposed by the analysis of the compositional, structural, and optical properties from a series of Ag/TiO 2 composites.

This work developed a facile colloidal route to synthesize BH 4 - -capped Pd x Ag y nanoparticles (NPs) in water using the reducing ionic liquids of [C n mim]BH 4 , and the resulting NPs were prone to form the nanocomposites with [amim] + -modified reduced graphene (RG). The removal of the metal-free inorganic ions of BH 4 - can create the profoundly exposed interfaces on the Pd x Ag y NPs during the electrooxidation, and favor the ethanol oxidation reaction (EOR) in lowering energy barrier. The counterions of [C n mim] + can gather ethanol, OH - ions, and the reaction intermediates on catalysts, and synergistically interact with RG to facilitate the charge transfer in nanocomposites. The interface-modified RG nanosheets can effectively segregate the Pd x Ag y NPs from aggregation during the EOR. Along with the small size of 4.7 nm, the high alloying degree of 60.2%, the large electrochemical active surface area of 64.1 m 2 g -1 , and the great peak current density of 1501 mA cm -2 mg -1 , Pd 1 Ag 2 @[C 2 mim]BH 4 -amimRG nanocomposite exhibits the low oxidation potentials, strong poison resistance, and stable catalytic activity for EOR in alkaline media, and hence can be employed as a promising anodic catalyst in ethanol fuel cells.