The electrochemical reduction of CO2 on catalyst surfaces is hindered by the inefficient mass transfer of CO2 in aqueous solutions. In this study, we employed an electrochemical reduction approach to fabricate a hydrophobic three-dimensional nanoporous silver catalyst with a plastron effect, aiming to enhance the CO2 diffusion. The resulting catalyst exhibited an exceptional performance with the FECO peaking at 95% at -0.65 V (vs. RHE) and demonstrated remarkable stability during continuous electrolysis for 48 hours. Control experiments, together with Tafel analysis, EIS measurements, and contact angle results, confirmed that the notable enhancement of performance was attributed to the hydrophobic porous structure that facilitated efficient storage and rapid mass transfer of low-solubility CO2 gas reactants.
The structure and properties of lignin can vary depending on the type of lignocellulosic biomass it comes from and the separation techniques used, and also affects its suitability for different applications. In this work, the structure and properties of lignin isolated from moso bamboo, wheat straw, and poplar wood by different treatment processes were compared. Results show that deep eutectic solvent (DES) extracted lignin exhibits well-preserved structures (including ß-O-4, ß-ß, and ß-5 linkages), a low molecular weight (Mn = 2300-3200 g/mol), and relatively homogeneous lignin fragments (1.93 < PDI < 2.33) compared to dealkaline lignin (DL) and milled wood lignin (MWL). Besides, lignin samples extracted by DES have a regular nanostructure, higher carbon residue content (>40 %), and excellent antioxidant properties (the free radical scavenging index >20). Among the three types of biomass, the structural destruction of lignin in straw is the most obvious, which is due to the degradation of ß-O-4 and ß-ß linkages during DES treatment. These findings can contribute to a better understanding of the structural changes that occur in various treatment processes from different lignocellulosic biomass, and help maximize the targeted development of their applications based on the characteristics of lignin.
Antioxidants , Lignin , Lignin/chemistry , Biomass , Molecular Weight
Bamboo pulp and papermaking produce a lot of bamboo powder waste, and its resource utilization is of great significance for biomass refining and environmental protection. Here, we propose an integrated approach involving mechanical activation, hydrothermal extraction, and deep eutectic solvents (DESs) multiple delignification for the efficient separation of bamboo powder. Among seven carboxylic acids based DESs, choline chloride (ChCl)-lactic acid (La) DES (1:1) is the most effective, with over 78.0% lignin removal and 88.9% cellulose retained after mechanical-hydrothermal (180 °C, 5 h)-DES (110 °C, 12 h) treatment. Notably, 84.7% of delignification is achieved after three times of ChCl-La DES treatment at 70, 90, and 110 °C respectively. The delignification rate is negatively correlated with the amount of carboxyl group in the DESs. The lower the pKa value, the higher the delignification rate. Additionally, the selectivity for lignin is improved with decreasing solvent polarity. DES treatment effectively degrades the guaiacyl unit lignin fractions and disrupts several ß-aryl-ether bonds (e.g., ß-O-4, ß-ß, and ß-5). Furthermore, DESs exhibit good recyclability, with less than 10% reduction in delignification after three cycles. Theory calculations confirm that ChCl-carboxylic acid DESs could compete with lignin to break hydrogen bonds in lignocellulosic biomass by providing their chloride, hydroxyl, and carboxyl groups. Overall, this study demonstrates the practical significance of multistage treatment for the effective fractionation of biomass into its three components.
Cellulose , Lignin , Lignin/chemistry , Powders , Biomass , Solvents/chemistry , Lactic Acid , Choline/chemistry , Hydrolysis
Swelling is a very common phenomenon in organic substances. However, the swelling behaviors of inorganic substances had rarely been reported. In this study, a new type of swellable organic-inorganic hybrid polymer (PIL@CHT) was designed and successfully synthesized through free-radical copolymerization of polymerizable phosphonium ionic liquid monomer and vinyl-functionalized hydrotalcite (CHT). The swelling behaviors of PIL@CHT in various solvents with a wide range of Hansen solubility parameters (δT) were investigated, and PIL@CHT exhibited excellent swellable capacity in the solvents with δT > 24.4 MPa1/2. The swollen state of the hybrid PIL@CHT in water presented a network structure with a diameter of approximately 8-12 µm, and CHT particles were well dispersed to the channel of PIL. PIL@CHT was applied to catalyze the CO2-assisted hydration of propylene oxide (PO), in which a cascade reaction including the cycloaddition of CO2 and PO and the subsequent hydrolysis of propylene carbonate (PC) occurred. PIL@CHT, combining the active sites of PIL and CHT, synergistically catalyzed this cascade reaction and achieved a high yield (93.0%) and selectivity (98.2%) of 1,2-propanediol (1,2-MPG) under a low H2O/PO ratio of 1.5/1. Moreover, the catalyst could be recycled seven times without any significant loss of catalytic activities and had good substrate generality.
Herein, novel nano-sized 1,1-diamino-2,2-dinitroethylene (C2H4N4O4, FOX-7)/zeolitic imidazolate framework-8 (ZIF-8) composites are constructed by facile liquid-assisted mechanochemical reactions. In contrast to two-step thermal decomposition of raw FOX-7, the prepared FOX-7/ZIF-8 composites demonstrate a single high-intensity exothermal decomposition attributed to the catalysis of ZIF-8. Benefiting from nano-sized energetic materials and the buffering effect of ZIF-8, the mechanical sensitives of FOX-7/ZIF-8 composites are decreased.
The design and fabrication of lithium secondary batteries with a high energy density and shape flexibility are essential for flexible and wearable electronics. In this study, we fabricated a high-voltage (5 V class) flexible lithium polymer battery using a lithium nickel manganese oxide (LiNi0.5Mn1.5O4) cathode. A LiNi0.5Mn1.5O4-hybridized gel polymer cathode (GPC) and a gel polymer electrolyte (GPE) membrane, both containing a sulfolane (SL)-based highly concentrated electrolyte (HCE), enabled the fabrication of a polymer battery by simple lamination with a metallic lithium anode, where the injection of the electrolyte solution was not required. GPC with high flexibility has a hierarchically continuous three-dimensional porous architecture, which is advantageous for forming continuous ion-conduction paths. The GPE membrane has significant ionic conductivity enough for reliable capacity delivery. Therefore, the fabricated lithium polymer pouch cells demonstrated excellent capacity retention under continuous deformation conditions. This study provides a promising strategy for the fabrication of scalable and flexible 5 V class batteries using GPC and GPE containing SL-based HCE.
Currently, available nanoscale anticancer drug delivery systems have low targeting and release efficiency, limiting their therapeutic effects. Thus, tumor-targeting nanocarriers for self-assembly of amphiphilic polymer-drug conjugates are urgently needed to improve drug targeting and treatment efficacy. Here, we report the construction of a stable, reduction-sensitive prodrug conjugate based on hyaluronic acid-grafted pH-sensitive doxorubicin (DOX). The amphiphilic prodrug copolymer self-assembled into spherical nanoparticles in aqueous solution and exhibited an average diameter of 150 nm. Prodrug micelles were stable in a normal physiological environment and achieve selective and rapid release under acidic pH and/or high reduction conditions. Cell Counting Kit-8, flow cytometry, and live cell imaging assays showed that the prodrug had high targeting and antitumor activity against CD44 receptors. Moreover, in vivo pharmacokinetics and biodistribution studies showed that the prodrug had a longer circulation time in BALB/c mice and higher accumulation in 4T1 tumors. Interestingly, the prodrug could effectively treat tumors with few side effects. These results showed that the DOX prodrug micelles developed in this study may have great potential in targeted therapy.
Nanoparticles , Neoplasms , Prodrugs , Animals , Drug Delivery Systems , Hyaluronic Acid , Mice , Mice, Inbred BALB C , Neoplasms/drug therapy , Oxidation-Reduction , Polymers , Tissue Distribution
For the development of energetic materials, insensitive compounds have attracted considerable attention due to their improved safety and lower cost than those of sensitive energetic compounds during production, transportation, and application. In this study, insensitive 4-aminofurazan-3-carboxylic acid amidrazone was used as a cation to obtain four derivatives which were determined by X-ray single crystal diffraction. It is interesting to note that all four derivatives are insensitive to impact and friction, while the velocities of detonation for derivatives are superior to that of insensitive TATB (1,3,5-triamino-2,4,6-trinitrobenzene). Multi-factors analysis shows that the cation of 4-aminofurazan-3-carboxylic acid amidrazone is a promising furazan-based cation in desensitizing energetic compounds.
Hypergolic ionic liquids (ILs) have shown a great promise as viable replacements for toxic and volatile hydrazine derivatives used as propellant fuels, and hence, have attracted increasing interest over the last decade. To take advantage of the reactivity and high energy density of the azido group, a family of low-cost and easily prepared azide-functionalized cation-based ILs, including fuel-rich anions, such as nitrate, dicyanamide, and nitrocyanamide anions, were synthesized and characterized. All the dicyanamide- and nitrocyanamide-based ILs exhibited spontaneous combustion upon contact with 100 % HNO3 . The densities of these hypergolic ILs varied in the range 1.11-1.29â g cm-3 , and the density-specific impulse, predicted based on Gaussianâ 09 calculations, was between 289.9 and 344.9â s g cm-3 . The values of these two key physical properties are much higher than those of unsymmetrical dimethylhydrazine (UDMH). Among the studied compounds, compound IL-3b, that is, 1-(2-azidoethyl)-1-methylpyrrolidin-1-ium dicyanamide, shows excellent integrated properties including the lowest viscosity (30.9â M Pa s), wide liquid operating range (-70 to 205 °C), shortest ignition-delay time (7â ms) with 100 % HNO3 , and superior density specific impulse (302.5â s g cm-3 ), suggesting promising applications with potential as bipropellant formulations.
A series of hypergolic ionic liquids (HILs) based on the cyano (1H-1,2,3-triazole-1-yl) dihydroborate anion were synthesized by introducing the {BH2-CN} moiety into the 1,2,3-triazole anion. This introduction allowed us to improve the self-ignition property and decrease the viscosity of ionic fuels. The synthesized series of HILs exhibited wide liquid operating ranges (>220 °C), high densities (>1 g cm-3), low viscosities (as low as 22.48 cP), and ignition delay (ID) times as short as 5 ms by using white fuming nitric acid (WFNA) as the oxidizer. Furthermore, these HILs can be ignited upon contact with a 90 wt% H2O2 oxidizer in the presence of iodine.
Redox-responsive ferrocene (Fc)-grafted supramolecular block copolymers functionalized with hyaluronic acid (HA-g-ß-CD/Fc-polymers or HAP) or folic acid (FA-g-ß-CD/Fc-polymers or FAP) were synthesized by host-guest interaction. The copolymer structures were characterized by Fourier transform infrared spectroscopy, nuclear magnetic resonance, and gel permeation chromatography. The block copolymers self-assemble into spherical micellar aggregates in aqueous solution, and exhibit reversible redox characteristics in the presence of an oxidant and reductant. The tunable redox response was evaluated by transmission electron microscopy, ultraviolet-visible spectroscopy, cyclic voltammetry and dynamic light scattering. The micelles rapidly release DOX under oxidative and acidic condition in vitro. Furthermore, presence of HA and FA on the micelles enabled effective uptake by the CD44 and FA receptor-overexpressing cancer cells. Taken together, the redox responsive Fc-block copolymer micelles have good biocompatibility, biodegradability, low toxicity, and high selectivity, and are a highly promising drug delivery system for cancer therapy.
The development of ionic-liquid-derived functional materials would be vital for stimulation of the interdisciplinary research in the fields of ionic liquid chemistry and material science. Here, a series of novel poly(ionic liquid)s with explosive capability were designed and prepared by introducing the energetic nitrato group and nitro-rich anions, such as nitrate, dinitramide, and nitroform into the polymeric chains. The as-synthesized explosive poly(ionic liquid)s (E-PILs) were fully characterized, and their physicochemical and detonation properties were investigated. All E-PILs show higher detonation performances than state-of-the-art energetic polymers including glycidyl azide polymer (GAP) and poly(glycidyl nitrate) [poly(GLYN)]. Some E-PILs exhibit higher calculated detonation velocities and pressures than 2,4,6-trinitrotoluene (TNT). These E-PILs are promising candidates for applications as new high-performance energetic polymers.
The design and synthesis of new hypergolic ionic liquids (HILs) as replacements for toxic hydrazine derivatives have been the focus of current academic research in the field of liquid bipropellant fuels. In most cases, however, the requirements of excellent ignition performances, good hydrolytic stabilities, and low synthetic costs are often contradictory, which makes the development of high-performance HILs an enormous challenge. Here, we show how a fuel-rich boranophosphate ion was rationally designed and used to synthesize a series of high-performance HILs with excellent comprehensive properties. In the design strategy, we introduced the {BH3 } moiety into the boranophosphate ion for improving the self-ignition property, whereas the complexation of boron and phosphite was used to improve the hydrolytic activity of the borohydride species. As a result, these boranophosphate HILs exhibited wide liquid operating ranges (>220 °C), high densities (1.00-1.10â g cm-3 ), good hydrolytic stabilities, and short ignition delay times (2.3-9.7â milliseconds) with white fuming nitric acid (WFNA) as the oxidizer. More importantly, these boranophosphate HILs could be readily prepared in high yields from commercial phosphite esters, avoiding complex and time-consuming synthetic routes. This work offers an effective strategy of designing boranophosphate HILs towards safer and greener hypergolic fuels for liquid bipropellant applications.
A novel family of hydrophobic triaminocyclopropenium cation based ionic liquids have been synthesized, and their structures and physicochemical properties characterized by NMR and IR spectroscopy, elemental analysis, differential scanning calorimetry, and hypergolic tests. The experimental results showed that all of these ionic liquids exhibited the expected hypergolic reactivity with the oxidizer white fuming nitric acid. Among them, the hypergolic ionic liquid based on the cyanoimidazolylborohydride anion showed excellent integrated properties, including high decomposition temperature (194 °C), high density (0.95â g cm-3 ), moderate viscosity (44â MPa s), ultrafast ignition delay time (6â ms), and high specific impulse (301.9â s); this demonstrates its potential as an environmentally friendly alternative to toxic hydrazine derivatives.
Hierarchical porous poly(ionic liquid)s (PILs) with high specific surface area were firstly synthesized via anion exchange. The exchange of bulky salicylate and its dimers/clusters in PILs by other smaller anions increased the specific surface area and fabricated a hierarchical porous structure. The high specific surface area and hierarchical porous structure prompted a high degree of exposure of the active sites and made the heterogeneous PIL catalysts contact with substrates sufficiently, enhancing their catalytic activity.
Ionic liquids have attracted a great deal of interest in recent years, illustrated by their applications in a variety of areas involved with chemistry, physics, biology, and engineering. Usually, the stabilities of ionic liquids are highlighted as one of their outstanding advantages. However, are ionic liquids really stable in all cases? This review covers the chemical stabilities of ionic liquids. It focuses on the reactivity of the most popular imidazolium ionic liquids at structural positions, including C2 position, N1 and N3 positions, and C4 and C5 positions, and decomposition on the imidazolium ring. Additionally, we discuss decomposition of quaternary ammonium and phosphonium ionic liquids and hydrolysis and nucleophilic reactions of anions of ionic liquids. The review aims to arouse caution on potential decomposition of ionic liquids and provides a guide for better utilization of ionic liquids.
Homogeneous catalysts generally show higher catalytic activities, while heterogeneous catalysts are more easily separated from products. To combine the advantages of heterogeneous and homogeneous catalysts has been of great interest for many years. Here, we report a kind of facilely prepared cross-linked poly(ionic liquid)s (PILs) with swelling property to increase catalytic activities of heterogeneous catalysts. The swelling ability of PILs was greatly affected by cross-linking density and chain length of substituents on imidazolium, and the unique swelling property prompted the nonporous PILs to contact with substrates sufficiently, enhancing their catalytic activities similar to homogeneous ionic liquid monomers.
A typical volcano-shaped curve has been found in heterogeneous catalytic systems containing titanosilicates for the first time. A new reactive intermediate with double H-bonds is proposed. Systematic results clearly evidence another H-bond formed between the high-electronegativity atom of the H-bond acceptor and the H(end) atom of Ti-Oα-Oß-H(end).
Several lines of evidence suggest that inflammation may play a role in the etiology of biliary tract cancers. To examine further the role of inflammation, we evaluated the associations between self-reported inflammatory-related medical conditions and the risk of biliary tract cancers in a population-based case-control study in Shanghai, China. Our analysis included 368 gallbladder cancer cases, 191 bile duct cancer cases, 68 ampulla of Vater cancer cases, and 959 healthy subjects. We used logistic regression to estimate odds ratios (ORs) and 95% confidence intervals (CIs) for biliary tract cancers in relation to six inflammation-related conditions. Gallbladder cancer was significantly associated with cholecystitis occurring at least 5 years prior to interview (OR = 1.7, 95% CI 1.1-2.9). Even though biliary stones did not significantly modify the associations between cholecystitis and gallbladder cancer, 90% of the gallbladder cancer cases with cholecystitis also had biliary stones, indicating that stones likely play an important role in the link between cholecystitis and gallbladder cancer. Among subjects who smoked and drank alcohol, a history of gastric (OR = 4.3, 95% CI 1.2-15.0) or duodenal ulcers (OR = 3.7, 1.2-12.0) was associated with an excess risk of gallbladder cancer. Although the mechanisms are unclear, our results further support the role for inflammation in the etiology of biliary tract cancers.
Biliary Tract Neoplasms/epidemiology , Gallbladder Neoplasms/epidemiology , Inflammation/epidemiology , Adult , Aged , Alcohol Drinking/epidemiology , Biliary Tract Neoplasms/pathology , Case-Control Studies , China/epidemiology , Cholecystitis/epidemiology , Cholecystitis/pathology , Female , Gallbladder Neoplasms/pathology , Gallstones/epidemiology , Gallstones/pathology , Humans , Inflammation/pathology , Logistic Models , Male , Marijuana Smoking/epidemiology , Middle Aged , Odds Ratio , Risk Factors , Ulcer/epidemiology , Ulcer/pathology
To evaluate the role of chronic inflammation in the development of gallstones and biliary tract cancer, we examined the risk associated with 62 single nucleotide polymorphisms (SNPs), in 22 inflammation-related genes, in a population-based case-control study conducted in Shanghai, China, where the incidence of biliary tract cancer has been increasing in recent decades. The study included 411 cases with biliary tract cancer (237 gallbladder, 127 extrahepatic bile duct, and 47 ampulla of Vater), 895 with biliary stones, and 786 controls randomly selected from the population. Unconditional logistic regression was used to calculate odds ratios and 95% confidence intervals for the association of individual SNPs and haplotypes with biliary stones and biliary tract cancer. Of the 62 SNPs examined, 14 were related to the risk of biliary cancer and stones. Specifically, variants in the IL8, IL8RB, RNASEL, and NOS2 genes were associated with biliary stones, whereas VEGF variants were associated with gallbladder cancer. Of the 10 genes with multiple SNPs from which we inferred haplotypes, only one IL8RB haplotype, consisting of 3 SNPs (rs2230054, rs1126579, and rs1126580), was associated with the risk of bile duct cancer (P = 0.003) and biliary stones (P = 0.02), relative to the most frequent haplotype. In summary, common variants in genes that influence inflammatory responses may predispose to gallstones and biliary tract cancer, suggesting the need for future studies into the immunologic and inflammatory pathways that contribute to biliary diseases, including cancer.
Biliary Tract Neoplasms/genetics , Inflammation/genetics , Population Surveillance , Biliary Tract Neoplasms/epidemiology , China , Humans , Polymorphism, Single Nucleotide , Risk Factors
