The robust synthetic flexibility of metal–organic frameworks (MOFs) offers a promising class of tailorable materials, for which the ability to tune specific physicochemical properties is highly desired. This is achie...
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The robust synthetic flexibility of metal–organic frameworks (MOFs) offers a promising class of tailorable materials, for which the ability to tune specific physicochemical properties is highly desired. This is achievable only through a thorough description of the consequences for chemical manipulations both in structure and dynamics. Magic angle spinning solid‐state NMR spectroscopy offers many modalities in this pursuit, particularly for dynamic studies. Herein, we employ a separated‐local‐field NMR approach to show how specific intraframework chemical modifications to MOF UiO‐66 heavily modulate the dynamic evolution of the organic ring moiety over several orders of magnitude.
Photo/electrochemical CO 2 splitting is impeded by the low cost‐effective catalysts for key reactions: CO 2 reduction (CDRR) and water oxidation. A porous silicon and nitrogen co‐doped carbon (SiNC) nanomaterial by ...
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Photo/electrochemical CO 2 splitting is impeded by the low cost‐effective catalysts for key reactions: CO 2 reduction (CDRR) and water oxidation. A porous silicon and nitrogen co‐doped carbon (SiNC) nanomaterial by a facile pyrolyzation was developed as a metal‐free bifunctional electrocatalyst. CO 2 ‐to‐CO and oxygen evolution (OER) partial current density under neutral conditions were enhanced by two orders of magnitude in the Tafel regime on SiNC relative to single‐doped comparisons beyond their specific area gap. The photovoltaic‐driven CO 2 splitting device with SiNC electrodes imitating photosynthesis yielded an overall solar‐to‐chemical efficiency of advanced 12.5 % (by multiplying energy efficiency of CO 2 splitting cell and photovoltaic device) at only 650 mV overpotential. Mechanism studies suggested the elastic electron structure of −Si(O)−C−N− unit in SiNC as the highly active site for CDRR and OER simultaneously by lowering the free energy of CDRR and OER intermediates adsorption.
Correction for ‘Selenium borohydride reaction as a versatile platform for the straightforward preparation of selenide-containing topological polymers’ by Chunlai Ding et al., Polym. Chem., 2017, DOI: 10.1039/c7py006...
Correction for ‘Selenium borohydride reaction as a versatile platform for the straightforward preparation of selenide-containing topological polymers’ by Chunlai Ding et al., Polym. Chem., 2017, DOI: 10.1039/c7py00676d.
Fischer-Tropsch synthesis（FTS） is a heterogeneous catalytic process for the change of synthesis gas into wide-range hydrocarbon fuels and high value chemicals. The iron-based catalysts supported on silica were synth...
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Fischer-Tropsch synthesis（FTS） is a heterogeneous catalytic process for the change of synthesis gas into wide-range hydrocarbon fuels and high value chemicals. The iron-based catalysts supported on silica were synthesized by autocombustion method using nitrate ion（N） and citric acid（CA）. The aim of this study is as-synthesized catalysts were used directly in fixed-bed reactor for FTS without further reduction. The effects of N/CA molar ratio of the catalysts were investigated by XRD, BET, H-TPR and SEM. With increase of N/CA molar ratio, the CO conversion and C selectivity of the catalyst increased at first, reached a maximum and then decreased. Results of the N/CA was 0.1 showed the highest CO conversion and C selectivity were about 70% and 76%, respectively. The addition of CA played a positive role to improve both CO conversion and selectivity. However, the excessive CA resulted in oversupply of the carbon residues which were coated on the catalysts and caused the decrease CO conversion and selectivity. Therefore, the advantage of autocombustion method may reveal another choice to synthesize catalyst without further reduction, notably the catalysts cannot be reduced at higher temperature.
Carboxylate as a promising and valuable directing group has attracted a great deal of ***,employing it as a traceless direction group has rarely been *** developed the ruthenium-catalyzed amidation of substituted benz...
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Carboxylate as a promising and valuable directing group has attracted a great deal of ***,employing it as a traceless direction group has rarely been *** developed the ruthenium-catalyzed amidation of substituted benzoic acids with isocyanates via directed C–H functionalization followed by decarboxylation to afford the corresponding metasubstituted N-aryl benzamides,in which the carboxylate serves as a unique,removable directing ***,this protocol can provide an efficient alternative to access meta-substituted N-aryl benzamides,which are much more difficult to prepare than ortho-substituted analogues.
The increasing number of microbreweries in recent years is a success by the variety of craft beers available in the pubs and markets. The beer is a beverage rich in phenolic compounds and antioxidants;however, little ...
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Hybrid organic–inorganic metal halide perovskites possess exceptional structural tunability, with three‐ (3D), two‐ (2D), one‐ (1D), and zero‐dimensional (0D) structures on the molecular level all possible. While...
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Hybrid organic–inorganic metal halide perovskites possess exceptional structural tunability, with three‐ (3D), two‐ (2D), one‐ (1D), and zero‐dimensional (0D) structures on the molecular level all possible. While remarkable progress has been realized in perovskite research in recent years, the focus has been mainly on 3D and 2D structures, with 1D and 0D structures significantly underexplored. The synthesis and characterization of a series of low‐dimensional organic tin bromide perovskites with 1D and 0D structures is reported. Using the same organic and inorganic components, but at different ratios and reaction conditions, both 1D (C 4 N 2 H 14 )SnBr 4 and 0D (C 4 N 2 H 14 Br) 4 SnBr 6 can be prepared in high yields. Moreover, photoinduced structural transformation from 1D to 0D was investigated experimentally and theoretically in which photodissociation of 1D metal halide chains followed by structural reorganization leads to the formation of a more thermodynamically stable 0D structure.
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