Search

[HO-EtMIm][OTf] efficiently catalyzes the dehydrative cyclization of vicinal diols under metal-free conditions, producing 1,4-dioxanes in 100% selectivity.

Benzyl phenyl sulfide is a kind of important chemicals with wide usages, which are mainly prepared through a nucleophilic reaction of thiophenol with benzyl chlorides or benzyl alcohols, suffering from inherent drawbacks, such as low efficiency, requirements for equivalent acid or base catalysts and formation of harmful byproducts and wastes. Herein, we report a green route to access various benzyl phenyl sulfide derivatives in good to excellent yields under mild conditions via the reaction of thioanisoles with benzyl alcohols over ionic liquid 1-propylsulfonate-3-methylimidazolium trifluoromethanesulfonate ([SO3HPrMIm][OTf]). Mechanism investigation indicates that the synergic effect of cation and anion of [SO3HPrMIm][OTf] activates thioanisoles and benzyl alcohols via hydrogen bonding, thus catalyzes the dehydration of benzyl alcohol to dibenzyl ether and the subsequent metathesis reaction between dibenzyl ether and benzyl phenyl sulfide, finally generating benzyl phenyl sulfide derivatives. This is a simple, highly efficient, and green approach to produce benzyl phenyl sulfide derivatives, which may have promising application potentials.

A solvent plays an important role in chemical synthesis. Herein, we report ionic liquid (IL)-promoted formylation of N(sp2)-heteroarenes with CO2 and H2 to produce formamides over the Pd/C nanocata...

The low separation efficiency of photogenerated charges and severe photocorrosion seriously impeded the application of CdS in photocatalytic water splitting. Here we report new routes to improve the photocatalytic performance of CdS nanowires (NWs) by decorating with Ag2S nanoparticles, so Ag2S/CdS heterojunction is constructed. The Ag2S/CdS heterojunction exhibited optimal photocatalytic H2 evolution rate of 777.3 μmol h−1 g−1, which is 12.1 times higher than that of pure CdS. The intrinsic characteristics of Ag2S/CdS nanocomposites, such as structure, optical properties, and surface chemical state are systematically studied by experimental characterizations and theoretical calculations. The comprehensive analysis demonstrates that the heterojunction between Ag2S and CdS accelerates photoinduced electrons transfer from CdS to Ag2S, enhancing their ability for water splitting. Meanwhile, the holes on the valence band of CdS react with the sacrificial agents, thus leading to the efficient separation of photogenerated electron–hole pairs. This work offers a simple route to synthesize one-dimensional CdS-based nanocomposites for efficient energy conversion driven by visible light.

Alcoholysis of propylene oxide (PO) is achieved over azolate ionic liquids (IL, e.g., 1-hydroxyethyl-3-methyl imidazolium imidazolate) at room temperature, accessing glycol ethers in high yields with excellent selectivity (e.g., >99%). Mechanism investigation indicates that cooperation of hydrogen-bonding of the anion with methanol and that of the cation with PO catalyses the reaction.

A novel four-site ionic liquid (IL) was designed via the neutralization of citrazinic acid with tetrabutylphosphonium hydroxide, which had the highest CO2 absorption capacity of 3.26 mol per molar ...

Single-atom metal catalysts (SAMCs) have high catalytic activity, but mass production of SAMCs with high metal loading remains challenging. In this work, a two-step and one-pot strategy is presente...

Lithium–sulfur (Li–S) batteries have been considered to be one of the most promising energy storage devices in the next generation. However, the insulating properties of sulfur and the shuttle effect of soluble lithium polysulfides (LiPSs) seriously hinder the practical application of Li–S batteries. In this paper, a novel porous organic polymer (HUT3) was prepared based on the polycondensation between melamine and 1,4-phenylene diisocyanate. The micro morphology of HUT3 was improved by in situ growth on different mass fractions of rGO (5%, 10%, 15%), and the obtained HUT3-rGO composites were employed as sulfur carriers in Li–S batteries with promoted the sulfur loading ratio and lithium-ion mobility. Attributed to the synergistic effect of the chemisorption of polar groups and the physical constraints of HUT3 structure, HUT3-rGO/S electrodes exhibits excellent capacity and cyclability performance. For instance, HUT3-10rGO/S electrode exhibits a high initial specific capacity of 950 mAh g−1 at 0.2 C and retains a high capacity of 707 mAh g−1 after 500 cycles at 1 C. This work emphasizes the importance of the rational design of the chemical structure and opens up a simple way for the development of cathode materials suitable for high-performance Li–S batteries.

N-formylation of amines with CO2/H2 is a green route to access N-formamides, which has been explored extensively in recent years. In this article, a heterogeneously catalytic system, “Ru/C+[Bmim][OAc]” was designed to catalyze the N-formylation of amines including primary, secondary and aryl amines under mild conditions, which afforded a series of N-formamides in good to excellent yields at 100 °C and 8 MPa (CO2:H2=3:5) without any additives. Detailed study indicates that [Bmim][OAc] plays multiple roles in the reaction process with activating amines through H-bonding interaction and modifying the Ru nanoparticles to improve their activities.

The low Coulombic efficiency and hazardous dendrite growth hinder the adoption of lithium anode in high-energy density batteries. Herein, we report a lithium metal-carbon nanotube (Li-CNT) composite as an alternative to the long-term untamed lithium electrode to address the critical issues associated with the lithium anode in Li-O

Photoreduction of carbon dioxide to chemicals or fuels is very interesting from the viewpoint of green chemistry. Herein, we report the photoreduction of CO2 catalyzed by a metal-free photocatalyst...

Direct hydrogenation of CO2 into formic acid is an atom-economic reaction, but it is thermodynamically limited, and the production of free formic acid is challenging. Herein, we report a protocol o...

ConspectusMetal-free catalysis is a promising protocol to access chemicals without metal contamination. Ionic liquids (ILs) that are entirely composed of organic cations and inorganic/organic anions have emerged as promising alternatives to molecular solvents and metal catalysts due to their unique properties such as structural tunability, the coexistence of multiple interactions among ions (e.g., electrostatic interaction, hydrogen bonding, van de Waals forces, acid/base interactions, hydrophilic/hydrophobic interactions, etc.), unique affinity for a wide range of chemicals, good chemical and thermal stability, and quite low volatility. ILs have shown potential applications in various chemical processes.In this Account, we systematically described our most recent work on IL-catalyzed approaches under metal-free conditions. The first section presents the IL-catalyzed strategies toward the transformation of CO2 to value-added chemicals, focusing on the CO2-reactive IL-catalyzed CO2 transformation to various heterocycles and the IL-catalyzed reductive transformation of CO2 to chemicals. In these approaches, we designed task-specific ILs that are able to chemically capture and activate CO2 via forming anion-based carbonate/carbamate or cation-based carboxylate/carbamate intermediates, thus further accomplishing its transformation to a series of heterocycles including quinazoline-2,4(1H,3H)-diones, cyclic carbonates, 2-oxazolidinones, oxazolones, and benzimidazolones under metal-free conditions. For the IL-catalyzed approaches to reducing CO2 with hydrosilanes to chemicals, we employed ILs capable of activating the Si-H bond in hydrosilanes and the N-H bond in amine substrates via H-bonding, thus achieving the reductive transformation of CO2 to formamides, benzimidazoles, and benzothiazoles via cooperative catalysis. The second section describes our finding on the IL-catalyzed hydration of the C≡C bond in propargylic alcohols. Azolate anion-based ILs that can chemically capture CO2 via the formation of carbamates could serve as robust nucleophiles to attack the C≡C bond in propargylic alcohols and then efficiently catalyze the hydration of propargylic alcohols to produce α-hydroxy ketones with the assistance of atmospheric CO2 gas under metal-free conditions. The third section unveils the cooperative catalysis strategy of hydrogen bond donors and acceptors of ILs for chemical reactions. In the hydrogen-bonding catalysis protocols, cations of the ILs act as H-bond donors and anions, as acceptors, forming H-bonds with the reactant molecules, respectively, in opposite ways, which can cooperatively catalyze the ring-closing C-O/C-O bond metathesis reactions of aliphatic diethers to O-heterocycles, the dehydrative etherification of alcohols to ethers, and direct oxidative esterification of alcohols to esters. We believe that these IL-catalyzed metal-free processes and strategies display promising practical applications, and their commercialization would bring great benefits to the production of the as-afforded value-added chemicals.

Synthesis of renewable acetic acid from CO2 and lignin was effectively achieved over an ionic liquid (e.g., [BMIm][Cl])-based catalytic system containing Ru–Rh bimetal catalyst (Ru3(CO)12 and RhI3) and LiI. As far as we know, this is the first initiative to produce acetic acid from lignin and CO2.

Developing efficient methods for the real-time detection of Zn2+ levels in biological systems is highly relevant to improving our understanding of the role of Zn2+ in the progression of Parkinson's disease (PD). In this work, a novel Schiff base based Zn2+ fluorescent probe (ZP) was designed, synthesized and systematically investigated. A significant turn-on effect on ZP upon the addition of Zn2+ was observed, accompanied by a blue-shift of the fluorescence spectra. ZP is sensitive to Zn2+ and has excellent selectivity against various biologically relevant cations, anions and amino acids. The sensing mechanism of ZP was studied by 1H NMR, MS, single crystal X-ray diffraction and theoretical calculations. The results showed that the response of ZP to Zn2+ was based on the chelation–hydrolysis-enhancement process. Upon bonding, Zn2+ hydrolyzes the Schiff base to an aldehyde precursor, the resulting aldehyde further coordinates to Zn2+ to form a more stable heterobimetallic complex leading to the emission enhancement and blue-shift. ZP was applied to imaging exogenous/endogenous Zn2+ in live HeLa cells. Furthermore, we successfully measured the Zn2+ levels using in vitro PD models, which provided a visualization method to better understand the relationship between Zn2+ levels and PD development.

A Rose bengal-functionalized porous organic polymer (RB-POP) was prepared with a specific surface area of up to 562 m2 g−1. In the presence of 1,8-diazabicyclo[5.4.0]undec-7-ene, RB-POP supported Ag(0) nanoparticles exhibited excellent performance for catalyzing cyclization of propargyl alcohols with CO2 at 30 °C, achieving a TOF of 5000 h−1, the highest value among the reported ones.

The reduction of CO2 with amines and H2 generally produces N-formylated or N-methylated compounds over different catalysts. Herein, we report the selective synthesis of formamides, 1,2-bis(N-heterocyclic)ethanes, and methylamines, which is achieved over an ionic liquid (IL, e.g., 1-butyl-3-methylimidazolium tetrafluoroborate, [BMIm][BF4])–Pd/C catalytic system. By simply varying the reaction temperature, formamides and methylamines can be selectively produced, respectively, in high yields. Interestingly, 1,2-bis(N-heterocyclic)ethanes can also be obtained via the McMurry reaction of the formed formamide coupled with subsequent hydrogenation. It was found that [BMIm][BF4] can react with formamide to form a [BMIm]+–formamide adduct; thus combined with Pd/C it can catalyze McMurry coupling of formamide in the presence of H2 to afford 1,2-bis(N-heterocyclic)ethane. Moreover, Pd/C–[BMIm][BF4] can further catalyze the hydrogenolysis of 1,2-bis(N-heterocyclic)ethane to access methylamine. [BMIm][BF4]–Pd/C was tolerant to a wide substrate scope, giving the corresponding formamides, 1,2-bis(N-heterocyclic)ethanes or methylamines in moderate to high yields. This work develops a new route to produce N-methylamine and opens the way to produce 1,2-bis(N-heterocyclic)ethane from cyclic amine as well.

O-heterocycles have wide applications, and their efficient and green synthesis is very interesting. Herein, we report hydrogen-bonding catalyzed ring-closing metathesis of aliphatic ethers to O-heterocycles over ionic liquid (IL) catalyst under metal- and solvent-free conditions. The IL 1-butylsulfonate-3-methylimidazolium trifluoromethanesulfonate ([SO3 H-BMIm][OTf]) is discovered to show outstanding performance, better than the reported catalysts. An interface effect plays an important role in mediating the reaction rate due to the immiscibility between the products and the IL catalyst, and the products can be spontaneously separated. NMR analysis and DFT calculation suggest that a pair of cation and anion of [SO3 H-BMIm][OTf] could form three strong H-bonds with an ether molecule, which catalyze the ether transformation via a cyclic oxonium intermediate. A series of O-heterocycles including tetrahydrofurans, tetrahydropyrans, morpholines and dioxane can be obtained from their corresponding ethers in excellent yields (e.g., >99 %). This work opens an efficient and metal-free way to produce O-heterocycles from aliphatic ethers.

Cocatalyst loading is an efficient strategy to accelerate the hydrogen evolution reaction, which is the final crucial process to complete photocatalytic hydrogen production and realize solar-to-hydrogen conversion. Herein, we report that N-doped vanadium carbide (NVC) is combined with Pt to form a multifunctional cocatalyst capable of enhancing carrier separation, activating H2O, and accelerating H2 evolution. Our designed Pt/NVC/C3N4 displays much higher photocatalytic activity than g-C3N4 loaded with Pt or NVC. The photocatalytic H2 evolution rate of Pt/NVC/C3N4 reaches 40 μmol/h, which is three times and one hundred times higher than that of Pt/C3N4 and NVC/C3N4, respectively. The significantly enhanced photocatalytic activity of Pt/NVC/C3N4 is attributed to the partial synergy between Pt and NVC, where NVC promotes carrier separation and activates H2O, and Pt is responsible for boosting proton reduction. Our work demonstrates that hybrid cocatalysts exhibit superior performance compared to traditional single-component cocatalysts, providing guidance for exploring highly active cocatalysts for photocatalysis.

Choline-based ionic liquids (Ch-ILs) with anions possessing interacting sites to attract CO2 were designed, which could capture CO2 with capacity >1.0 mol CO2 per molar IL under ambient conditions. Moreover, this kind of ILs combining with CuCl could catalyze the formylation of amines with CO2/H2 at 120 °C. Especially, choline imidazolate showed the best performance, affording a series of N-formamides in excellent yields. It was demonstrated that the IL activated CO2 and the synergistic effect between the IL and CuCl resulted in the high activity for catalysing the formylation of amines with CO2/H2.

Nitroreductase (NTR) is a member of flavin-containing enzymes that exists widely in bacteria. Hypoxia, which is a characteristic of locally advanced solid tumors, resulting from an imbalance between oxygen consumption and supply, can result in NTR overexpression. Using either nicotinamide adenine dinucleotide (NADH) or nicotinamide adenine dinucleotide phosphate (NADPH) as a source of reducing equivalents, NTR can catalyze the reduction of nitroaromatic compounds to the corresponding amines. Based on this reduction mechanism, NTR can be applied not only in the bioremediation and degradation of organic nitrogen compounds, but also in the development of NTR-targeted fluorescent probes to detect the hypoxic status of cancer cells. This review aims to provide a summary of the progress in fluorescent probes for NTR in recent years and elucidate the main fluorescent mechanisms that have been applied to design probes.

Surface band bending and composition of Ga-polar n-GaN with different surface treatments were characterized by using angular dependent X-ray photoelectron spectroscopy. Upward surface band bending of varying degree was observed distinctly upon to the treatment methods. Besides the nitrogen vacancies, we found that surface states of oxygen-containing absorbates (O-H component) also contribute to the surface band bending, which lead the Fermi level pined at a level further closer to the conduction band edge on n-GaN surface. The n-GaN surface with lower surface band bending exhibits better linear electrical properties for Ti/GaN Ohmic contacts. Moreover, the density of positively charged surface states could be derived from the values of surface band bending.

Solar-energy-driven photoreduction of CO2 to hydrocarbon fuels is an interesting and challenging topic, which generally requires photocatalysts with the capability to capture and photoreduce CO2 simultaneously. Herein, we demonstrate that a N,O,P-containing covalent organic polymer (NOP-COP) prepared via condensation of hexachlorocyclotriphosphazene with barbituric acid can capture CO2 and further photocatalyze its reduction to CH4 under visible-light irradiation. The characterization information indicates that the incorporation of phosphorus in the skeleton of NOP-COP promoted the absorption of visible light and improved the lifetime of the photoinduced carriers. As a result, NOP-COP exhibited enhanced efficiency for photoreduction of CO2 compared with the N,O-containing polymer, affording CH4 as the sole carbonaceous product with a rate of 22.5 μmol gcat–1 h–1 and selectivity over 90%. This work provides insight into designing and fabricating polymeric photocatalysts for CO2 photoreduction to fuels.

Although metal nitride thin films have attractive prospects in plasmonic applications due to its stable properties in harsh environments containing high temperatures, shock, and contaminants, the effect of deposition parameters on the properties of the metallic ZrN grown on III-N semiconductors by pulse laser deposition still lacks of detailed exploration. Here we have successfully prepared metallic ZrN x films on p-GaN substrate by pulsed laser deposition in N 2 ambient of various pressures at a fixed substrate temperature (475 °C). It is found that the films exhibit quite smooth surfaces and (111) preferred orientation. The X-ray photoelectron spectroscopy measurements indicate that carbon contamination can be completely removed and oxygen contamination is significantly reduced on the film surfaces after cleaning using Ar + sputtering. The N/Zr ratio increases from 0.64 to 0.75 when the N 2 pressure increases from 0.5 Pa to 3 Pa. The optical reflectivity spectra measured by the UV–vis–NIR spectrophotometer show that the ZrN x is a typical and good metallic-like material and its metallic properties can be tuned with changing the film compositions.

CO2 incorporation into C–H bonds is an important and interesting topic. Herein a sequential protocol for C(sp)–H carboxylation by employing a metal-free C–H activation/catalytic silylation reaction in conjunction with KO t Bu-mediated carboxylation with CO2 was established, in which KO t Bu catalyzes silylation of terminal alkynes to form alkynylsilanes at low temperature, and simultaneously mediates carboxylation of the alkynesilanes with atmospheric CO2. Importantly, the carboxylation further promotes the silylation, which makes the whole reaction proceed very rapidly. Moreover, this methodology is simple and scalable, which is characterized by short reaction time, wide substrate scope, excellent functional-group tolerance and mild reaction conditions, affording a range of corresponding propiolic acid products in excellent yields in most cases. In addition, it also allows for a convenient 13C-labeling through the use of 13CO2.

A mesoporous imine-functionalized organic polymer (Imine-POP) was prepared based on the reaction of an aryl ammonium salt with an aromatic aldehyde in water without any catalyst and template. The Pd coordinated Imine-POP exhibited high catalytic activity for the N-formylation of amines with CO2/H2 at 100 °C, affording a series of formamides in high yields.

The CO2-involved synthesis of chemicals is of great significance from a green and sustainable point of view. Herein, we present an efficient Co-based catalytic system composed of a commercially available Co salt, the tetradentate phosphine ligand P-(CH2CH2PPh2)3, and a base, denoted as [Co]/PP3/base, for the synthesis of formamides via the formylation of amines with CO2/H2. It was indicated that the selectivity of products (i.e., formamide or methylamine) could be tuned to some extent via changing the solvent and the base. Using ethanol as the solvent, the Co(ClO4)2·6H2O/PP3/K2CO3 system showed high activity for the production of formamides, affording product yields of 82–95%, together with its broad substrate scope. Exploration of the reaction mechanism indicated that formamide was formed with HCOOH as the intermediate, while the methylamine byproduct was produced with HCHO as the intermediate via the hydrogenolysis of dialkylaminomethane.

The methylation of amines using methanol is a promising route to synthesize N-methylamines, and the development of cheap and efficient catalytic system for this reaction is of great significance. Herein, we reported a cobalt (Co)-based catalytic system, which was in situ formed from commercially available Co precursor and a tetradentate phosphine ligand P(CH2CH2PPh2)3 combined with K3PO4. This catalystic system was very effective for the selective production of dimethylated products from aliphatic amines and monomethylated ones from aromatic amines. The reaction mechanism was further investigated by control and isotope labelling experiments.

Etching of GaN/AlGaN heterostructure by O-containing inductively coupled Cl 2 /N 2 plasma with a low-energy ion bombardment can be self-terminated at the surface of the AlGaN layer. The estimated etching rates of GaN and AlGaN were 42 and 0.6 nm/min, respectively, giving a selective etching ratio of 70:1. To study the mechanism of the etching self-termination, detailed characterization and analyses were carried out, including X-ray photoelectron spectroscopy (XPS) and time-of-flight secondary ion mass spectroscopy (TOF-SIMS). It was found that in the presence of oxygen, the top surface of the AlGaN layer was converted into a thin film of (Al,Ga)O x with a high bonding energy, which effectively prevented the underlying atoms from a further etching, resulting in a nearly self-terminated etching. This technique enables a uniform and reproducible fabrication process for enhancement-mode high electron mobility transistors with a p-GaN gate.

A series of tetrabutylphosphonium ([Bu4P]+)-based ionic liquids (ILs) with multiple-site for CO2 capture and activation in their anions are reported, which could efficiently catalyze the cyclization reaction of propargylic alcohols with CO2 at ambient conditions. Especially, the IL, [Bu4P]3[2,4-OPym-5-Ac], which has three interaction sites for attracting CO2 together with a pKa1 value of 9.13, exhibited the best performance, affording a series of α-alkylidene cyclic carbonates in moderate to good yields. The mechanism exploration demonstrated that IL served as a bifunctional catalyst with anion simultaneously activat-ing CO2 via multiple-site cooperative interactions and the C≡C triple bond in propargylic alcohol via inductive effect, thus resulting in the production of α-alkylidene cyclic carbonates..

Herein we present a simple, metal-free and versatile route to synthesize unsymmetrically N,N-disubstituted formamides (NNFAs) from CO2, primary amine and aldehyde promoted by ionic liquid (1-butyl-3-methylimidazolium chloride) at room temperature. This approach features wide scopes of amines and aldehydes, and various unsymmetrical NNFAs could be obtained in good to excellent yields. The ionic liquid can be reused at least five runs without obvious activity loss.

Pyridine-containing anion-based ionic liquids (PA-ILs) with two kinds of interaction sites to bind CO2, e.g., [P4444][2-OP], were found to be highly efficient for catalysing the cycloaddition reactions of atmospheric CO2 with epoxides at room temperature under metal- and halogen-free conditions, producing a series of cyclic carbonates in high yields. It was demonstrated that the cooperative interaction from two interaction sites in the anions of PA-ILs activated CO2, while the cation activated the epoxides substrates via coordination to the central P+ unit, thus resulting in the high activity of the IL catalysts.

Mesoporous Troger's base-functionalized polymers (Meso-TBPs) were prepared using a sulfonic acid group functionalized ionic liquid/H2O system, with surface areas up to 431 m2 g−1 and pore sizes of 3–15 nm. Ir(II) coordinated Meso-TBPs exhibited extraordinary catalytic performance in the N-methylation of amines using methanol.

Amorphous AlSnO ( a -ATO) thin films have been synthesized by a combustion solution process at low temperatures, with the Al:Sn molar ratio of 1: x ( x = 11 − 7) in the precursors. The influence of compositions on the structural, optical, and electrical properties of AlSnO (ATO) films were investigated in detail. The X-ray diffraction patterns revealed that all the ATO films are amorphous in nature. All elements were distributed uniformly over the films, regardless of holes formed in the matrix with increasing Al contents. The a -ATO films had an average transmittance over 80% in the visible region, with enlarged optical band gap energies from 3.42 to 3.67 eV at elevated Al contents. Hall-effect measurements identified that weak p -type conductivity could be obtained at the high Al doping levels with Al:Sn ratios higher than 1:9. The realization of p -type a -ATO films by the combustion solution method may open a door to design p -type amorphous-oxide-semiconductor thin-film transistors for transparent electronics.

The chemical transformation of atmospheric CO2 is of great significance yet still poses a great challenge. Herein, azole-anion-based aprotic ionic liquids (ILs) were synthesized by the deprotonation of weak proton donors (e.g., 2-methylimidazole, 4-methylimidazole, and 2,4-dimethylimidazole) with tetrabutylphosphonium hydroxide, [Bu4P][OH]. We found that these ILs, such as [Bu4P][2-MIm], could activate atmospheric CO2 through the formation of carbamates. The resultant carbamate intermediates could further react with various types of substrate, including propargylic alcohols, 2-aminobenzonitriles, ortho-phenylenediamines, and 2-aminothiophenol, thereby producing α-alkylidene cyclic carbonates, quinazoline-2,4(1 H,3 H)-diones, benzimidazolones, and benzothiazoline, respectively, in moderate-to-good yields. Thus, we have achieved the transformation of CO2 at atmospheric pressure, and we expect this method to open up new routes for the synthesis of various oxygen-containing heterocyclic compounds under metal-free conditions.

The synthesis of hierarchically mesoporous polymers with multiple functionalities is challenging. Herein we reported a template-free strategy for synthesis of phenolic azo-polymers with hierarchical porous structures based on diazo-coupling reaction in aqueous solution under mild conditions. The resultant polymers have surface areas up to 593 m(2) g(-1) with the mesopore ratio of80 %, and a good ability to complex with metal ions, such as Cu(2+) , Zn(2+) ,Ni(2+) , achieving a metal loading up to 26.24 wt %. Moreover, the polymers complexed with Zn showed excellent performance for catalyzing the reaction of CO2 with epoxide, affording a TOF of 2570 h(-1) in the presence of tetrabutyl ammonium bromide (7.2 mol %). The polymer complexed with Cu could catalyze the oxidation of alcohol with high efficiency.

Visible-light-driven photoreduction of CO2 to energy-rich chemicals in the presence of H2 O without any sacrifice reagent is of significance, but challenging. Herein, Eosin Y-functionalized porous polymers (PEosinY-N, N=1-3), with high surface areas up to 610 m2 g-1 , are reported. They exhibit high activity for the photocatalytic reduction of CO2 to CO in the presence of gaseous H2 O, without any photosensitizer or sacrifice reagent, and under visible-light irradiation. Especially, PEosinY-1 derived from coupling of Eosin Y with 1,4-diethynylbenzene shows the best performance for the CO2 photoreduction, affording CO as the sole carbonaceous product with a production rate of 33 μmol g-1 h-1 and a selectivity of 92 %. This work provides new insight for designing and fabricating photocatalytically active polymers with high efficiency for solar-energy conversion.

Fast, efficient capture and safe storage of radioactive iodine is of great significance in nuclear energy utilization but still remains a challenge. Here we report imidazolate ionic liquids (Im-ILs) for rapid and efficient capture, and reliable storage of iodine. These Im-ILs can chemically capture iodine to form I-substituted imidazolate ILs with an iodide counterion and the newly formed ILs can absorb iodine to form polyiodide species and low-temperature eutectic salts. For example, choline imidazolate shows iodine capture capacities of 8.7 and 17.5 g of iodine per gram of IL at 30 and 100 oC, respectively, which are, to the best of our knowledge, higher than the values (0.5–4.3 g/g) reported to date. Importantly, iodine can be stably stored in the Im-IL absorbent systems even at 100 oC. The Im-ILs have potential for application in the capture and storage of radioactive iodine. Efficient capture of iodine has important applications in nuclear waste processing. Here a class of imidazolate-derived ionic liquids are shown to chemically capture up to 17.5 grams of iodine per gram of ionic liquid at useful temperatures.

B(C6F5)3 combined with atmospheric CO2 was found to be highly effective for the cyclization of ortho-substituted aniline derivatives with N,N-dimethylformamide (DMF), and a series of N-containing heterocycles including benzothiazoles, benzimidazoles, quinazolinone and benzoxazole were obtained in good to excellent yields.

A novel bathocuproine (BCP) derivative 4,7-bis(3,5-bis(trifluoromethyl)phenyl)-2,9-dimethyl-1,10-phenanthroline (BCP-2CF3) was synthesized and investigated as a candidate for exciton blocking layers (EBLs) in organic solar cells. The impacts of BCP-2CF3 and BCP on the performance of photovoltaic devices were studied for bulk-heterojunction (BHJ) devices with a blend of poly[N-9′′-hepta-decanyl-2,7-carbazole-alt-5,5-(4′,7′-di-2-thienyl-2′,1′,3′-benzothiadiazole)] (PCDTBT) and [6,6]phenyl-C61-butyric acid methyl ester (PC61BM). In comparison with BCP, BCP-2CF3 showed a comparable improvement in the power conversion efficiency (PCE) (ca. 39%), and moreover a better thermal stability. Organic photovoltaic (OPV) devices with BCP-2CF3 withstood an annealing temperature as high as 100 °C, while those with BCP revealed a loss about 90% of the original efficiency at the same temperature. The newly designed principle for BCP-derived EBL materials opens a window for systematic enhancement of the efficiency and especially durability of organic solar cells.

The construction of the C–S bond using CO2 as a C1 feedstock can be considered as a green route for the synthesis of S-containing compounds and is of great significance. Herein, we report the acetate-based ionic liquids (ILs)-catalyzed synthesis of benzothiazoles via cyclization of 2-aminothiophenols with CO2 and hydrosilane under mild conditions (e.g., 60 °C, 0.5 MPa). It was found that the IL (e.g., 1-butyl-3-methylimidazolium acetate, [Bmim][OAc]) served as a multifunctional catalyst with activating CO2 and hydrosilane to form a formoxysilane intermediate, as well as simultaneously activating 2-aminothiophenols through a hydrogen bond, finally resulting in the production of benzothiazoles. [Bmim][OAc] showed the best performance, and a series of benzothiazoles were obtained in high yields. To the best of our knowledge, this is the first protocol for the synthesis of benzothiazoles using CO2 as a C1 building block under metal-free and mild conditions.

Ultrathin two-dimensional (2D) crystalline materials show high specific surface area (SA) of high energy (HE) facets, imparting a significant improvement in their performances. Herein we report a novel route to synthesize TiO2 nanofilms (NFs) with atomic thickness (2.0 nm) through a solvothermal reaction mediated by the hydrogen-bonding networks constructed by hydroquinone (HQ). The resultant TiO2 NFs have nearly 100 % exposed (001) facets and give an extremely high SA up to 487 m(2) g(-1) . The synergistic effect of HQ and choline chloride plays a vital role in the formation of TiO2 NFs and in the exposure of HE (001) facets. Because of its ultrathin feature and exposed (001) facet, the N2 -annealled TiO2 NFs showed fast kinetics of lithium insertion/extraction, demonstrating foreseeable applications in the energy storage.