Solvent Compatibility Research Articles

Investigation of the effects of solvent-mismatch and immiscibility in normal-phase × aqueous reversed-phase liquid chromatography

Comprehensive two-dimensional liquid chromatography (LC × LC) is an attractive separation technique that allows achieving high peak capacities and information on chemical correlations. Unfortunately, its application in industrial practice is still not widespread due to limiting factors such as complex method development, tedious method optimization and solvent-incompatibility (such as solvent-strength mismatch or immiscibility experienced during fraction transfer).A severe case of solvent-incompatibility is encountered in the comprehensive coupling of normal-phase LC and reversed-phase LC (NPLC × RPLC). NPLC × RPLC is considered a desirable LC × LC system, especially for the characterization of synthetic polymers, due to the high orthogonality of the two retention mechanisms. However, its experimental realization often suffers from solvent-injection effects in the RPLC dimension, such as peak-deformation, peak-splitting, or even unretained elution (“breakthrough”) of sample components. Such a decrease in performance or loss of retention is highly dependent on the types of solvents used.To explore the boundaries of solvent compatibility, we applied large-volume injections (LVI) of reference analytes (e.g. alkyl benzenes; ethoxylate and propoxylate polymers) dissolved in water-immiscible sample solvents, such as dichloromethane, n-hexane, and isooctane in fast water-based gradient RPLC separations (using methanol or acetonitrile as eluent). It was found that, when using highly aqueous initial gradient conditions, hydrophobic sample diluents were retained and eluted during the applied gradient. Depending on the relative retention of the retained diluent and the sample analytes, good chromatograms for LVI of immiscible solvents were obtained, comparable with injections under ideal conditions. The conclusions from injection experiments in aqueous RPLC were verified by coupling an NPLC system with a gradient from isooctane to tetrahydrofuran and an RPLC system with a gradient from water to acetonitrile in an online comprehensive NPLC × RPLC separation of a mixture of propoxylate polymers. The separation provided separation of the polymers based on their number of hydroxyl end-groups (NPLC) and oligomer chain-length (RPLC), without suffering from significant band-broadening effects due to solvent-mismatch upon injection in the second-dimension RPLC system.

Characterization and optimization of a rapid, automated 3D-printed cone spray ionization-mass spectrometry (3D-PCSI-MS) methodology

3D-printed cone spray ionization-mass spectrometry (3D-PCSI-MS) is an ambient ionization technique developed for the rapid, in-situ analysis of bulk solids and trace analytes within solid matrices. A reproducibly fabricated 3D-printed cone is used as the collection device, the extraction chamber, and the spray-based ionization source. Herein, we discuss the material selection based on the extraction and spray solvent compatibility with conductive plastic types, the strength of the selected material, and the advantages and disadvantages of the cone geometry. The ease of printing and the required parameters for reproducible manufacturing is also documented. To allow for improved sample throughput, reproducible positioning, and automated solvent delivery and analysis, an autosampler was developed from commercial-off-the-shelf (COTS) parts and custom 3D-printed pieces. Finally, the application of this automated sampling via 3D-PCSI-MS on a field portable mass spectrometer was demonstrated for environmental, defense, and forensic applications.

Two-Dimensional Nanomaterials for Boosting the Performance of Organic Solar Cells

The thin-film organic solar cells (OSCs) are currently one of the most promising photovoltaic technologies to effectively harvest the solar energy due to their attractive features of mechanical flexibility, light weight, low-cost manufacturing, and solution-processed large-scale fabrication, etc. However, the relative insufficient light absorption, short exciton diffusion distance, and low carrier mobility of the OSCs determine the power conversion efficiency (PCE) of the devices are relatively lower than their inorganic photovoltaic counterparts. To conquer the challenges, the two-dimensional (2D) nanomaterials, which have excellent photoelectric properties, tunable energy band structure, and solvent compatibility etc., exhibit the great potential to enhance the performance of the OSCs. In this review, we summarize the most recent successful applications of the 2D materials, including graphene, black phosphorus, transition metal dichalcogenides, and g-C3N4, etc., adapted in the charge transporting layer, the active layer, and the electrode of the OSCs, respectively, for boosting the PCE and stability of the devices. The strengths and weaknesses of the 2D materials in the application of OSCs are also reviewed in details. Additionally, the challenges, commercialization potentials, and prospects for the further development of 2D materials-based OSCs are outlined in the end.

Role of Solvent Compatibility in the Phase Behavior of Binary Solutions of Weakly Associating Multivalent Polymers.

Condensate formation of biopolymer solutions, prominently those of various intrinsically disordered proteins (IDPs), is often driven by “sticky” interactions between associating residues, multivalently present along the polymer backbone. Using a ternary mean-field “stickers-and-spacers” model, we demonstrate that if sticker association is of the order of a few times the thermal energy, a delicate balance between specific binding and nonspecific polymer–solvent interactions gives rise to a particularly rich ternary phase behavior under physiological circumstances. For a generic system represented by a solution comprising multiassociative scaffold and client polymers, the difference in solvent compatibility between the polymers modulates the nature of isothermal liquid–liquid phase separation (LLPS) between associative and segregative. The calculations reveal regimes of dualistic phase behavior, where both types of LLPS occur within the same phase diagram, either associated with the presence of multiple miscibility gaps or a flip in the slope of the tie-lines belonging to a single coexistence region.

Lithium-Titanate As Electrode Material for Aprotic Systems

This article briefly describes experiments which investigate the mutual compatibility of aprotic solvents with higher fire safety and Lithium Titanate Oxide (LTO) as the negative electrode material for lithium-ion batteries. The work follows the current trend of enhancing fire safety by using new kinds of aprotic solvents along with a new generation of electrode materials which fulfil the intended using of lithium-ion batteries for high power applications, e.g. electric vehicle propulsion. In our work, the examiner of using sulfolane electrolyte (SL) and Li4Ti5O12 (LTO) under various ambient temperatures. The influence of electrolyte on the proper operation and stability of negative electrode material was considered. The measurements were performed in the temperature range from 25 °C up to 80 °C with half-cell connection. Our main objective of these experiments was to prove and investigate a proper operation of an aprotic electrolyte with higher fire safety together with LTO negative material under high ambient temperatures.

Rational Design and Facile Synthesis of Dual-State Emission Fluorophores: Expanding Functionality for the Sensitive Detection of Nitroaromatic Compounds.

Six novel benzimidazole-based D-π-A compounds 4 a-4 f were concisely synthesized by attaching different donor/acceptor units to the skeleton of 1,3-bis(1H-benzimidazol-2-yl)benzene on its 5-position through an ethynyl link. Due to the twisted conformation and effective conjugation structure, these dual-state emission (DSE) molecules show intense and multifarious photoluminescence, and their fluorescence quantum yields in solution and solid state can be up to 96.16 and 69.82 %, respectively. Especially, for excellent photostability, obvious solvatofluorochromic and extraordinary wide range of solvent compatibility, DSE molecule 4 a is a multifunctional fluorescent probe for the visual detection of nitroaromatic compounds (NACs) with the limit of detection as low as 10-7 M. The quenching mechanism has been proved as the results of photoinduced electron transfer and fluorescence resonance energy transfer processes. Importantly, probe 4 a can sensitively detect NACs not only in real water samples, but also on 4 a-coated strips and 4 a@PBAT thin films.

In situ extraction (milking) of the two promising Botryococcus braunii strains Showa and Bot22 under optimized extraction time

In situ extraction or “milking” of microalgae is a promising approach to reduce downstream costs in order to produce low-value substances such as lipids from microalgae in an economical way. Due to its ability to secrete high amounts of long-chain hydrocarbons to an extracellular matrix, the green microalga Botryococcus braunii is suitable for the process of in situ extraction as the cost intensive steps of harvesting, dewatering, and cell disruption could be omitted. Based on a previous study investigating various B. braunii strains in terms of growth, lipid accumulation, and solvent compatibility, the B. braunii strains Showa and Bot22 (both B race) were identified as potential candidates for the process of in situ extraction. In order to prove the suitability of these two strains for the process of in situ extraction, this study first determined the optimal extraction time using short-term in situ extraction over 7 days at different starting biomass concentrations of 1.5 and 2.5 g L−1. Furthermore, both strains were treated applying the optimal extraction time in long-term in situ extractions for 30 days to confirm the results from the short-term extractions. The results indicate a strain-dependent optimal extraction time of 300 min day−1 for strain Showa and 200 min day−1 for strain Bot22. During long-term in situ extraction for 30 days, hydrocarbon productivity was 16.99 mg L−1 day−1 (10.53 mg gDW−1 day−1) for strain Showa and 14.53 mg L−1 day−1 (10.48 mg gDW−1 day−1) for strain Bot22. Furthermore, a direct correlation between hydrocarbon productivity achieved by in situ extraction and the hydrocarbon concentration in the biomass of the respective strain could be established. It could be shown that the consideration of the effective extraction time and the phase boundary area is required to calculate an extraction system independent value for the comparison of different extraction setups.

Simultaneous Analysis of the Metabolome and Lipidome Using Polarity Partition Two-Dimensional Liquid Chromatography-Mass Spectrometry.

Comprehensive metabolic profiling is a considerable challenge for systems biology since the metabolites in biological samples have significant polarity differences. A heart-cutting two-dimensional liquid chromatography-mass spectrometry (2D-LC-MS) method-based polarity partition was established to analyze both the metabolome and lipidome in a single run. Based on the polarity partition strategy, metabolites with high polarity were retained and separated by one-dimensional hydrophilic chromatography, while low- and medium-polarity lipids were collected into a sample loop and injected into two-dimensional reversed-phase chromatography for separation. A simple online dilution strategy realized the online coupling of the 2D-LC-MS, which effectively solved band broadening and peak distortion caused by solvent incompatibility. Moreover, a dual gradient elution procedure was introduced to further broaden the coverage of low-polarity lipids. The metabolites' log P values, which this 2D-LC-MS method could analyze, ranged from -8.79 to 26.86. The feasibility of the 2D-LC-MS system was demonstrated by simultaneous analysis of the metabolome and lipidome in rat plasma related to depression. A total of 319 metabolites were determined within 40 min, including organic acids, nucleosides, carbohydrate derivatives, amino acids, lipids, and other organic compounds. Finally, 44 depression-related differential metabolites were screened. Compared with conventional LC-MS-based methods, the 2D-LC method covered over 99% of features obtained by two conventional methods. In addition, the selectivity and resolution of the hydrophilic metabolites were improved, and the matrix effects of the hydrophobic metabolites were reduced in the developed method. The results indicated that the established 2D-LC system is a powerful tool for comprehensive metabolomics studies.

Boosting practical high voltage lithium metal batteries by butyronitrile in ether electrolytes via coordination, hydrolysis of C[tbnd]N and relatively mild concentration strategy

Currently ether solvents have been regarded as the most compatible organic solvents with lithium metal in electrolytes of lithium batteries. However, ether solvents are unstable under high voltage (>4.0 V), and prone to side reactions with nickel-rich high-voltage cathode materials. In this work, a novel dual-solvent electrolyte in ethylene glycol dimethyl ether (DME) and butyronitrile (BN) mixed solvent was designed and fabricated for Li/LiNi0.5Mn0.3Co0.2O2-based lithium metal batteries. When charged to high voltage 4.3 V, the battery cycled in this optimal electrolyte can maintain the capacity at 133.7 mAh g−1 with a retention of 88.84% after 150 cycles at 0.2 C and −10 °C. During long-term cycling, the battery also exhibits excellent cycling performance with capacity maintained at about 112.0 mAh g−1 after 500 cycles at 1 C and −10 °C. BN has strong oxidation resistance and high conductivity, which can inhibit the decomposition of ether solvents under high voltage and improve the low temperature performance of battery effectively. Additionally, the cyano (–CN) group in BN molecular has a strong coordination ability with the high-valent metal ions and can mask the active ions on the cathode, correspondingly reducing the corrosion of cathode material by the electrolyte. Moreover, cyano group can participate in the hydrolysis to remove trace amounts of water and acidic by-products such as HF in the electrolyte. Therefore, the boosting effect of butyronitrile for ether solvents can provide a promising strategy for enhancing the performance of high voltage lithium metal batteries for practical industrialization.

Printed Lithium for Next Generation Battery Technologies

Next generation lithium ion batteries will need to utilize anode materials that offer higher energy density and faster charging rates compared to graphite anode. However, widespread commercialization of anodes containing more than a few percent of high energy density materials such as silicon and tin has been hindered by issues such as high first cycle inefficiency and poor cycle life. Loss of active lithium from cathode materials due to SEI formation permanently lowers the cell energy density. Pre-lithiation employs an external, sacrificial source of lithium to offset active lithium losses during the first cycle, allowing more efficient use of lithium from the cathode and therefore raising the cell energy density1,2,3.Livent has developed a proprietary approach to pre-lithiation called Printable Lithium Technology (PLT) that incorporates SLMP into a stable printable formulation. Printable Lithium Formulation (PLF) is comprised of SLMP dispersed in a compatible solvent along with other rheology and performance modifiers to create a formulation that is chemically stable and not prone to separation for extended periods of time. The technology is scalable using industry standard equipment to apply the formulation to the surface of a prefabricated anode. Printable Lithium Technology (PLT) is anode and cathode chemistry agnostic4,5,6. PLT can be used in anodes with a range of silicon content, because lithium loading could be accurately controlled based on the applications’ requirements. Lithium loading control is achieved through the print head designed for pattern printing. We will also discuss safety benefits of using our approach.Figure 1a shows the dQ/dV curve of for baseline SiO/Li half-cell compared to a half-cell with PLF treated SiO. Figure 1a shows the absence of solvent reduction peak in the 0.4V – 0.2V range for the cell incorporating PLT, indicating PLF eliminate the irreversible capacity loss. The voltage vs. capacity curve on the right shows that the first cycle efficiency (FCE) has been improved from 69% in the baseline cell to 87% in the cell with PLT incorporated. Initial voltage is lowered from 1.6V to 0.2V in the cell with treated anode.It can be seen in Figure 2 that PLT can be used in a variety of cell chemistries to improve the cell FCE. Figure 1

Designing and Demystifying the Lithium Metal Interface toward Highly Reversible Batteries.

Reversible lithium (Li) plating/stripping is essential for building practical high-energy-density batteries based on Li metal chemistry, which unfortunately remains a severe challenge. In this contribution, it is demonstrated that through the rational regulation of strong Li+ -anion coordination structures in a highly compatible low-polarity solvent, 2-methyl tetrahydrofuran, the Li plating/stripping assisted by a nucleation modulation procedure delivers a remarkably high average Coulombic efficiency under rather demanding conditions (99.7% and 99.5% under 1.0mAcm-2 , 3.0mAh cm-2 and 3.0mAcm-2 , 3.0mAh cm-2 , respectively). The exceedingly reversible cycling obtained herein is fundamentally correlated with the flattened Li deposition and minimized solid electrolyte interphase (SEI) generation/reconstruction in the customized condition, which notably restrains the growth rates of both dead Li0 (0.0120mAh per cycle) and SEI-Li+ (0.0191mAh per cycle) during consecutive cycles. Benefiting from the efficient Li plating/stripping manner, the assembled anode-free Cu|LiFePO4 (2.7mAh cm-2 ) coin and pouch cells exhibit impressive capacity retention of 43.8% and 41.6% after 150 cycles, respectively, albeit with no optimization on the test conditions. This work provides guidelines into the targeted interfacial design of high-efficiency working Li anodes, aiming to pave the way for the practical deployment of high-energy-density Li metal batteries.

Solution‐Processed Chemically Non‐Destructive Filter Transfer of Carbon‐Nanotube Thin Films onto Arbitrary Materials

AbstractFilter‐transfer methods of single‐walled carbon‐nanotube (SWNT) thin films have been widely employed to fabricate state‐of‐the‐art electronics and photonics devices with highly transparent and conductive electrodes; however, a challenge remains for all solution‐processable technologies to overcome substrates’ destruction due to their solvent incompatibility. Here, an advanced method of transferring SWNT thin films onto arbitrary material substrates by adopting chemically stable and flexible polytetrafluoroethylene (PTFE) membranes is reported. Filtrated SWNT thin films on PTFE membranes (PTFE@SWNTs) press‐freely adhere to not only flat but curved substrates by their solvent‐wettability and flexibility natures, and are spontaneously transferred after low‐temperature evaporation of the wet solvents and peeling of the PTFE membrane. SWNT thin films transferred onto polyethylene terephthalate films show sheet resistance values of ≈400 Ω □−1 at ≈90% transmittance, which are drastically decreased to ≈50 Ω □−1 at ≈65% from ≈100 Ω □−1 at ≈80%. The wet solvents are suitably displaced based on solvent‐compatibility experiments with the substrates. Topically, it is demonstrated that the solvent‐wetted PTFE@SWNT can be non‐destructively placed onto a perovskite (CH3NH3PbI3) substrate via the as‐displaced various organic solvents. A pre‐doping process of PTFE@SWNTs is possible by using a HNO3 aqueous solution. The HNO3‐doped SWNT thin film is successfully transferred onto the perovskite substrate.

Colloidal magnesium hydroxide Nanoflake: One-Step Surfactant-Assisted preparation and Paper-Based relics protection with Long-Term Anti-Acidification and Flame-Retardancy

Enhancing the interfacial dispersion and suspension stability is crucial for magnesium hydroxide (Mg(OH)2) nanomaterials in the long-term deacidification of paper-based cultural relics. However, because of the low specific surface area and the poor solvent compatibility of as-prepared large-sized Mg(OH)2, it often tends to agglomerate and settle down during the usage and storage, that is harmful for paper protection due to its unevenly deacidification and nonuniformly distribution on paper cellulose. Herein, we propose a feasible preparation of colloidal Mg(OH)2 ultrathin nanoflakes with high dispersion stability via a simple one-step surfactant-assisted strategy. The surfactant acts as both a structure-direct agent to confine the growth of Mg(OH)2 with rich active sites and a surface modifier to enhance its solvent adaptability and dispersion stability, avoiding the common fussy procedure with additional steric stabilizer. Owing to the evenly interaction with free acid species therein and the uniformly distribution on the paper fiber as alkaline reserve, the as-obtained Mg(OH)2 presents the superior paper protection performance characterized by its safer pH of 7.29 for the original aged paper (pH = 5.03) and the excellent long-term anti-acidification effect with competitive pH of 5.47 after accelerated-aging at 105 °C for 5 months. Furthermore, Mg(OH)2 nanoflakes with surfactant-modified structure also endue them as an improved flame retardant for multifunctional paper protection. The protection with Mg(OH)2 has little effect on the paper surface properties and cellulose crystallinity, in line with the principle of least intervention. This work will put forward a feasible way toward colloidal Mg(OH)2 nanoflakes with excellent paper protection performance, shedding light on the development of emerging protection materials for paper-based cultural relics.

Microwave-assisted solid-phase synthesis of nitrogen-doping carbon dot with good solvent compatibility and its sensing of sunitinib.

Microwave-assisted solid-phase synthesis method was simple, convenient, and fast, and herein adopted to produce nitrogen-doping carbon dots (N-CDs) in only 3min. The N-CDs possessed high fluorescence quantum yield up to 15.9% with satisfactory stability to the environmental pH, ionic strength, and ultraviolet radiation. Particularly, the N-CDs had excellent dispersibility in both water and water-compatible organic solvents with similar fluorescence properties. Sunitinib, a small-molecule tyrosine inhibitor effective for some solid tumors, was found to quench the fluorescence of N-CDs in these media via the inner-filter effect. Hence, it was convenient to combine the proper sample pretreatment with the N-CD probe for sensing sunitinib avoiding the medium incompatibility problem. For rat plasma sample, salting-out liquid-liquid extraction was employed to minimize the sample matrix and concentrate the target sunitinib from aqueous to acetonitrile. The fluorescence detection of sunitinib was then achieved in acetonitrile by the addition of the proper amount of N-CDs. The method provided a good linearity of 0.1μg/mL to 7μg/mL with a limit of detection of 30ng/mL, which met the requirement of the therapeutic drug monitoring of sunitinib. The developed method was potential for on-site detection of sunitinib.

Facile Deposition of Silver Nanoparticles on Photonic Cellulose Nanocrystals Films: A Study on Solvent Stability and Post Antibacterial Activity

AbstractCellulose nanocrystals (CNCs) incorporated with silver nanoparticles (AgNPs) photonic films have drawn considerable attention due to their plasmonic chiroptical activity. However, the exploitation of some fundamental properties for practical use such as the affinity analysis of metal nanoparticles attached to the surface of photonic films according to the solvent compatibility and antibacterial activity under physical conditions has yet not been studied. Hence, a facile process of in situ deposition of AgNPs into the chiral structure of CNC films is proposed. CNC photonic films, cross‐linked by glutaraldehyde are prepared. This interaction generated the solvents‐stable photonic film with a considerable amount of unreacted aldehyde functional groups that facilitates the reduction of Ag salt to AgNPs. The formed AgNPs in the photonic films show excellent stability over immersion in various polar and non‐polar solvents. The post‐solvent treated photonic films display excellent contact‐based antibacterial behavior against gram‐negative Escherichia coli.

Electroforming-free nonvolatile resistive switching of redox-exfoliated MoS2 nanoflakes loaded polystyrene thin film with synaptic functionality

Here, we report robust and highly reproducible nonvolatile resistive switching (RS) devices with artificial synaptic functionalities utilizing redox-exfoliated few-layered 2H-MoS2 nanoflakes. Advantageous polar solvent compatibility of 2D MoS2 from this method were utilized to fabricate thin film devices very easily and cost-effectively using polystyrene as matrix. Prominent RS property of polystyrene thin film devices with varying MoS2 concentrations strongly favors electroforming-free operation. The conduction band position of 2D MoS2 nanosheet in combination with the work functions of chosen electrodes looks alleviating to switch the current from low to high at a suitable positive bias voltage. We further confirmed the mechanism of charge transport through fitting the results with theoretical models, say injection-dominated Schottky emission model for low-conducting states and space-charge-limited current mechanism for the high-conducting state. Interestingly, a relatively high current On/Off ratio 102 was recorded during the pump-probe testing to show resistive random-access memory (ReRAM) application. Finally, artificial synaptic functionalities- the building blocks of neuromorphic computing architectures is also illustrated by considering the robust RS property and ReRAM application.

Scalable Production of Lipid Nanoparticles Containing Amphotericin B.

Lipid-based formulations have been developed to improve stability profiles, tolerability, and toxicity profiles of small molecule drugs. However, manufacture of such formulations involving lipophilic compounds can be labor-intensive and difficult to scale because of solubility and solvent compatibility issues. We have developed a rapid and scalable approach using rapid-mixing techniques to generate homogeneous lipid nanoparticle (LNP) formulations of siRNA, triglycerides, and hydrophilic weak-base drugs. Here, we used this approach to entrap a hydrophobic small molecule, Amphotericin B (AmpB), a hydrophobic drug not soluble in ethanol. The three prototypes presented in this study were derived from LNP-siRNA systems, triglyceride nanoparticles, and liposomal systems. Cryogenic transmission electron microscopy (cryo-TEM) revealed that all three LNP-AmpB formulations retain structural characteristics of the parent (AmpB-free) LNPs, with particles remaining stable for at least 1 month. All formulations showed similar in vitro toxicity profiles in comparison to AmBisome. Importantly, the formulations have a 2.5-fold improved IC50 for fungal growth inhibition as compared to AmBisome in in vitro efficacy studies. These results demonstrate that the rapid-mixing technology combined with dimethyl sulfoxide (DMSO) for drugs insoluble in other organic solvents can be a powerful manufacturing method for the generation of stable LNP drug formulations.

Additive-Free Solution Processing of Carbon Nanotubes in Industrial Solvents

Carbon nanotubes can now be produced in the ton scale in the form of powders, but they need to be further processed, usually by solution-based routes, into disaggregated and more usable forms for applications. There has been extensive effort to search and design solvents that can disperse nanotubes, which can also be easily removed afterward. We have discovered that cresols, which are already manufactured for other industrial purposes, are such solvents. They can disperse carbon nanotube powders of many types at unprecedentedly high concentrations, rendering them polymer-like rheological and viscoelastic properties, and high processability. This makes carbon nanotube powders immediately usable by current materials-processing techniques for creating desirable structures or composites.Using cresols as a minority cosolvent, unfunctionalized carbon nanotubes can be dispersed in many common industrial solvents. Spectroscopic studies reveal that cresol forms a charge-transfer complex with carbon nanotubes, which is destabilized in high-dielectric-constant solvents but remains stable in low-dielectric-constant solvents. The new chemical insight enables scalable technical solutions for solving a longstanding problem of solution processing of carbon nanotubes. For example, volatile compatible solvents, such as n-hexane and chloroform, can be used as the main solvent to formulate fast-evaporating nanotube inks for high-throughput techniques, such as airbrushing, to quickly create continuous and conformal carbon nanotube coatings. Meanwhile, incompatible solvents such as acetone can help remove residual high-boiling-point cresols without the usual need for heating.

Improved CO2 separation performance and interfacial affinity of composite membranes by incorporating amino acid-based deep eutectic solvents

• ADES was chosen as CO 2 carrier to prepare composite membrane for CO 2 separation. • The asymmetric distribution of ADES in the membrane is realized. • DFT calculations were used to investigate the CO 2 separation mechanisms. • The composite membrane presented potential to break through the “trade-off” effect. Increasing concentration of CO 2 in the atmosphere has drawn attention to the mitigation of global warming. In order to develop an efficient and cost-effective CO 2 capture technology, a defect-free asymmetric composite membrane based on amino acid-based deep eutectic solvent (ADES) and Pebax 1657 was assembled. ADES is a novel alternative to ionic liquids for CO 2 capture, synthesized from natural substances through simple processes, which has the basic characteristics of ionic liquids and is environmentally friendly. The asymmetric distribution of ADES in the membrane is achieved by solvent compatibility design. Under the synergistic effect of multiple factors, the composite membrane shows outstanding gas separation performance. Compared with the neat Pebax membrane, the CO 2 /N 2 selectivity of the composite membrane is increased by 17%, while the CO 2 permeability is reduced by less than 0.6%. Density functional theory (DFT) calculations were also conducted to investigate the interaction mechanism between composite membrane and gas molecules.

All‐polymer solar cells with over 16% efficiency and enhanced stability enabled by compatible solvent and polymer additives

AbstractConsidering the robust and stable nature of the active layers, advancing the power conversion efficiency (PCE) has long been the priority for all‐polymer solar cells (all‐PSCs). Despite the recent surge of PCE, the photovoltaic parameters of the state‐of‐the‐art all‐PSC still lag those of the polymer:small molecule‐based devices. To compete with the counterparts, judicious modulation of the morphology and thus the device electrical properties are needed. It is difficult to improve all the parameters concurrently for the all‐PSCs with advanced efficiency, and one increase is typically accompanied by the drop of the other(s). In this work, with the aids of the solvent additive (1‐chloronaphthalene) and the n‐type polymer additive (N2200), we can fine‐tune the morphology of the active layer and demonstrate a 16.04% efficient all‐PSC based on the PM6:PY‐IT active layer. The grazing incidence wide‐angle X‐ray scattering measurements show that the shape of the crystallites can be altered, and the reshaped crystallites lead to enhanced and more balanced charge transport, reduced recombination, and suppressed energy loss, which lead to concurrently improved and device efficiency and stability.