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Cyclopropane-based high-energy fuels possess high intramolecular energy and density, and their precise synthesis is a critical challenge. However, owing to the highest strain in the cyclopropane structure (compared to other four- or five-membered rings, etc.), metal-carbene intermediates form with difficulty, resulting in poor catalytic selectivity for its synthesis. Herein, through rational design of π−π stacking between the Pd organic complex and graphene, we report a single-site Pd catalyst for precise synthesis of multicyclopropane-based high-energy fuels. It is discovered that π−π stacking enhanced the electrophilicity of Pd through a weak metal−support interaction, thus promoting the formation of Pd═C carbene active intermediates. Meanwhile, the adsorption between the active centers and intermediates was enhanced via π−π stacking. These two respects led to almost twice selectivity for cyclopropanation reaction up to 80.5% as that without π−π stacking. This work provides an effective strategy of π−π noncovalent interactions for regulating C−C coupling reaction selectivity.

Fluorinated ionic liquids (ILs) are well-known as electrolytes in the nitrogen (N2) electroreduction reaction due to their exceptional gas solubility. However, the influence of fluorinated functional group on N2solvation and solubility enhancement remains unclear. Massive molecular dynamics simulations and free energy perturbation methods are conducted to investigate the N2solubility in 11 traditional and 9 fluorinated ILs. It shows that the fluorinated IL of 1-Ethyl-3-methylimidazolium tris(pentafluoroethyl) trifluorophosphate ([Emim]FAP) exhibits ultrahigh solubility, 4.844 × 10–3, approximately 118 times higher than that of traditional IL 1-Ethyl-3-methylimidazolium nitrate ([Emim]NO3). Moreover, fluorinated ILs with more than 10 C–F bonds possess higher N2solubility than others and show an exothermic nature during solvation. As the C–F bonds number in ILs decreases, the N2solubility decreases significantly and displays the opposite endothermic behavior. To understand the ultrahigh N2solubility in fluorinated ILs, we propose a concept of fluorine densification energy (FDE), referring to the average strength of interaction between atoms per unit volume in ILs with fluorine domains, demonstrating a linear relationship with C–F bonds. Physically, lower FDE results in lower N2–anion pair dissociation energy and higher free volume, finally enhancing the N2solubility. Consequently, medium to long alkyl fluorine tails within a polar environment defines a distinct fluorine domain, emphasizing FDE’s role in enhancing N2solubility. Overall, these quantitative results will not only deepen the understanding of N2solvation in ILs but may also shed light on the rational design of IL-based high-performance N2capture and conversion technologies.

The electrochemical dimerization of acrylonitrile (AN) to adiponitrile (ADN) is an essential process for nylon-66 production, but this process still faces many challenges such as low energy conversion efficiency and poor selectivity. Herein, various ionic liquids (ILs) were used as electrolyte additives to evaluate their effects on the electrochemical dimerization of AN. The addition of IL significantly enhanced the performance of the electrolytic reaction and inhibited the hydrogen evolution reaction (HER). The electrolyte containing Tetrabutylphosphonium bromide (TBPB) showed the highest faraday efficiency of adiponitrile (FEADN) of 84.5% and excellent stability at an optimal current density of 200 mA cm–2. Molecular dynamics (MD) simulations revealed that TBPB was uniformly dispersed in the electrolyte and formed a “long brush” hydrophobic layer with appropriate wettability on the electrodes. Moreover, it was observed that ILs with a more symmetrical cationic structure exhibited a better hydrophobic layer effect, favoring the dimerization of AN to ADN.

Membrane channel proteins (MCPs) play key roles in matter transport through cell membranes and act as major targets for vaccines and drugs. For emerging ionic liquid (IL) drugs, a rational understanding of how ILs affect the structure and transport function of MCP is crucial to their design. In this work, GPU-accelerated microsecond-long molecular dynamics simulations were employed to investigate the modulating mechanism of ILs on MCP. Interestingly, ILs prefer to insert into the lipid bilayer and channel of aquaporin-2 (AQP2) but adsorb on the entrance of voltage-gated sodium channels (Nav). Molecular trajectory and free energy analysis reflect that ILs have a minimal impact on the structure of MCPs but significantly influence MCP functions. It demonstrates that ILs can decrease the overall energy barrier for water through AQP2by 1.88 kcal/mol, whereas that for Na+through Nav is increased by 1.70 kcal/mol. Consequently, the permeation rates of water and Na+can be enhanced and reduced by at least 1 order of magnitude, respectively. Furthermore, an abnormal IL gating mechanism was proposed by combining the hydrophobic nature of MCP and confined water/ion coordination effects. More importantly, we performed experiments to confirm the influence of ILs on AQP2in human cells and found that treatment with ILs significantly accelerated the changes in cell volume in response to altered external osmotic pressure. Overall, these quantitative results will not only deepen the understanding of IL-cell interactions but may also shed light on the rational design of drugs and disease diagnosis.

Abstract: Quantum chemical calculations of the structures and cation-anion interaction of 1-ethyl-3-methylimidazolium lactate ([Em-im][ LAC]) ion pair at the B3LYP/6-31++G** theoretical level were performed. The relevant geometrical characteristics, energy properties, intermolecular H-bonds (H-bonds), and calculated IR vibrations with respect to isolated ions were systematically discussed. The natural bond orbital (NBO) and atoms in molecule (AIM) analyses were also employed to understand the nature of the interactions between cation and anion. The five most stable geometries were verified by analyzing the relative energies and interaction energies. It was found that the most of the C-H…O intermolecular H-bonds interactions in five stable conformers have some covalent character in nature. The elongation and red shift in IR spectrum of C-H bonds which involve in H-bonds is proved by electron transfers from the lone pairs of the carbonyl O atom of [LAC]− to the C-H antibonding orbital of the [Emim]+. The interaction modes are more favorable when the carbonyl O atoms of [LAC]− interact with the C2-H of the imidazolium ring and the C-H of the ethyl group through the formation of triple H-bonds.

Abstract: To solve the inherent disadvantages in conventional processes for electrodeposition of zinc, it’s necessary to develop more high-efficiency and environmentally friendly electrolytes. In this work, it was found that the dissolution of ZnO was remarkably enhanced in some imidazolium chloride by the addition of urea, and the solubility of ZnO in 1:1 [Amim]Cl/urea mixture was as high as 8.35 wt% at 373.2 K. Electrochemical measurements showed that zinc could be readily electrodeposited from the solutions of ZnO. Bright, dense and well adherent zinc coatings with good purity were obtained from 0.6 M solution of ZnO in 1:1 [Amim]Cl/urea at 323.2–343.2 K. It’s expected that the solutions of ZnO in imidazolium chloride/urea mixtures have the potential to replace the traditional electrolytes, especially toxic zinc chloride-based ones for zinc electroplating, as well as preparation of zinc materials.

Abstract: Ionic liquids (ILs) have been widely used in separation, catalysis, electrochemistry, etc., and one of the most outstanding characteristics is that ILs can be tailored and tuned for specific tasks. In order to design and make better use of ionic liquids, the structures and properties relationship is indispensable. Both molecular dynamics and Monte Carlo simulations have been proved useful to understand the behavior of molecules at the microscale and the properties of the system. However, the quality of such simulations depends on force field parameters describing the interactions between atoms. All-atom (AA) or the united-atom (UA) force fields will be chosen because of the demand for more exact results or the lower computational cost, respectively. In order to make a systematic comparison of the two force fields, molecular simulations for four kinds of acyclic guanidinium-based ionic liquids (cations: (R2N)2C=N+<, anion: nitric or perchloric acid) were performed based on the AA and the UA force fields in this work. AA force field parameters were derived from our previous work (Fluid Phase Equilib., 2008, 272: 1–7), and the UA parameters were proposed in this work. Molecular dynamics simulation results for the AA and UA force fields were compared. Simulation densities are very similar to each other. Center of mass radial distribution functions (RDFs), site to site RDFs and spatial distribution functions (SDFs) were also investigated to depict the microscopic structures of the ILs.

With 3D framework structure and special corner-sharing characteristics, natrium superionic conductors (NASICONs) can vary their crystal structure with temperature change or on cation insertion/desertion, serve as both electrode and electrolyte materials, which make them fascinating in energy storage applications. However, those structure characteristics also bring about challenges on the understandings of charge transport mechanism, such as the precise cation/electron diffusion passage and the means to enhance or adjust it. Herein this review, we take typical NASICONs, the single ion conductor, Na3Zr2Si2PO12(NZSP) and ion/electron mixed conductor, Na3V2(PO4)3(NVP) as the examples, and briefly review the studies on charge transport mechanism as well as the strategy to enhance it. We find that doping is the mostly viable method to increase both ionic and electronic conductivity, while, considering the different roles that NASICON may act in energy storage, special attention should be paid on the doping effect. Typical doping elements were classified by their functions, such as working on the SE bulk, grain boundary, or enrich the vacancies. We found that some elements could enhance both σiof NZSP and σeof NVP, while most of the σeresults were obtained on pallet level, therefore, advanced particle-level electronic conductivity testing method or instrument is required.

The implementation of synthetic polymer membranes in gas separations, ranging from natural gas sweetening, hydrogen separation, helium recovery, carbon capture, oxygen/nitrogen enrichment, etc., has stimulated the vigorous development of high-performance membrane materials. However, size-sieving types of synthetic polymer membranes are frequently subject to a trade-off between permeability and selectivity, primarily due to the lack of ability to boost fractional free volume while simultaneously controlling the micropore size distribution. Herein, we review recent research progress on microporosity manipulation in high-free-volume polymeric gas separation membranes and their gas separation performance, with an emphasis on membranes with hourglass-shaped or bimodally distributed microcavities. State-of-the-art strategies to construct tailorable and hierarchically microporous structures, microporosity characterization, and microcavity architecture that govern gas separation performance are systematically summarized.Keywords: Gas separation membranes; Hierarchical microporosity; Micropore size distribution; Configurational free volume; Solution–diffusion mechanism.

The influencing mechanism of catalyst calcination atmospheres on the crystallinity, acidity, and alkylation stability of CeX zeolites. (EFAL: extra-framework aluminum species; CeX-O-O: CeX zeolite suffered from double-calcination in air; CeX-N-N: CeX zeolite suffered from double-calcination under nitrogen; B350: Brønsted acid concentration determined by pyridine adsorption-FTIR at 350 °C).

Ionic liquids (ILs) hold great promise in the fields of green chemistry, environmental science, and sustainable technology due to their unique properties, such as a tailorable structure, the various types available, and their environmentally friendly features. On the basis of multiscale simulations and experimental characterizations, two unique features of ILs are as follows: (1) strong coupling interactions between the electrostatic forces and hydrogen bonds, namely in the Z-bond, and (2) the unique semiordered structure and properties of ultrathin films, specifically regarding the quasi-liquid. In accordance with the aforementioned theoretical findings, many cutting-edge applications have been proposed: for example, CO2capture and conversion, biomass conversion and utilization, and energy storage materials. Although substantial progress has been made recently in the field of ILs, considerable challenges remain in understanding the nature of and devising applications for ILs, especially in terms of e.g. in situ/real-time observation and highly precise multiscale simulations of the Z-bond and quasi-liquid. In this Perspective, we review recent developments and challenges for the IL research community and provide insights into the nature and function of ILs, which will facilitate future applications.

A series of tunable-acidity vanadium phosphorus oxide (VPO) catalysts modified by layered double oxide (LDO) were first fabricated by a mechanical milling approach. The optimum Zn2Mg1Al1O-VPO sample achieved 63.2% yield of maleic anhydride (MA), which is 8.9% higher than that of Blank-VPO. Various characterizations were used to explore the relationship between the surface properties such as the crystal structure, surface P/V ratio, surface acidity, and catalytic performance. The NH3-TPD and pyridine IR analysis demonstrated that the appropriate surface acidity could significantly improve the performance of the VPO catalyst. A synergistic catalysis mechanism between the Lewis and Brønsted acid sites is tentatively proposed to enhance the catalytic performance of VPO. The Lewis acid sites accelerate the C–H bond activation and cleavage, thereby increasing the conversion of n-butane. Moreover, the Brønsted acid sites can stabilize the reaction intermediates and facilitate the desorption of MA, consequently improving the selectivity of MA.

Frustrated Lewis pairs (FLPs) containing sterically hindered Lewis acidic and basic sites can capture and react with N2and CO2, thus furnishing a new strategy for urea electrosynthesis. Herein, the rice-like InOOH nanoparticles coupled with the well-defined FLPs (i.e., In In-OH) were synthesized and exhibited a urea yield rate of 6.85 mmol h−1g−1and faradic efficiency of 20.97% at −0.4 V versus reversible hydrogen electrode. Systematic investigations reveal that the electron-deficient Lewis acidic In sites and electron-rich Lewis basic In-OH achieve the targeted chemisorption of the N2and CO2molecules by electronic interaction respectively. The bonding and antibonding orbitals of reactant molecules interact with the unoccupied orbitals of Lewis acid and nonbonding orbitals of Lewis base to generate the desired intermediates for urea synthesis in artificial FLPs. In addition, FLPs can further ensure the orbital-matched intermediates of ∗N=N∗ and CO proceed with the desirable C–N coupling reaction to produce ∗NCON∗ precursors.

Silicon-based anode materials attract ever-increasing attention owing to their high theoretical capacity. However, their practical application is significantly hindered by the dramatic volume change during the charge/discharge process, during which not only the solid electrolyte interface (SEI) but also the electrode might be ruined. Here, we propose a H-bond network-regulated binder by introducing low-molecular-weight cross-linkers, lithium oxalate and α-cyclodextrin (α-CD), into alginate (Alg). The balance between the binding strength and Li ion diffusion is realized through the control of the ratio between them. Lithium oxalate and α-CD can effectively regulate the H-bond network of the binder by forming intermolecular dynamic H bonds with Alg and reducing the intramolecular ones. Although the hybrid binder shows lower adhesion force than Alg, better electrode integrity is obtained during the charge/discharge process. Meanwhile, Li+transportation is facilitated due to extra Li+supplied by lithium oxalate, thereby achieving better rate capability.

The development of self-healing polymers can extend the service life of polymer materials. However, it is still a challenge to prepare a polyurethane with high healing efficiency and maximum retention of the properties of polyurethane itself. In this research, we proposed a new scheme for the industrial production of self-healing polyurethane and successfully synthesized a self-healing polyurethane using diacetyl oxime as the chain extender and triethanolamine as the cross-linking agent. Oxime-blocked isocyanates deblock at a higher temperature and regenerate oxime urethanes at a lower temperature, thereby achieving thermal reversibility and self-healing due to the concise and efficient thermal reversible reaction of oxime urethanes. Fourier transform infrared and differential scanning calorimetry experiments confirmed that the oxime urethanes in the polyurethane deblock efficiently at around 90 °C and re-block after the temperature is lowered. The process can be cycled at least three times. Microscopic observation confirmed that the cracks disappeared within 60–90 min at 90 °C. The tensile test shows that the synthetic DiO-c-PU has a self-healing efficiency of over 94% at 90 °C for 1.5 h, which is more efficient. From the results, it appears that DiO-c-PU has good self-healing properties.

Conducting fibers with improved properties and functionalities are needed for diverse applications. Here we report the fabrication of core/shell conductive Dacron fibers by dip-coating method through originating from multi-walled carbon nanotubes (MWCNTs) coated on polyester fibers. The annealing process was conducted to enhance interaction between the conductive shell and polyester core as well as within the MWCNTs network. The properties of two kinds of MWCNTs dispersions and the electrical properties of conductive fibers were studied, respectively. The results show that both MWCNTs-polyurethane resin (MWCNTs-WPU) dispersion and MWCNTs-acrylic resin (MWCNTs-PAA) dispersion present a typical characteristic of pseudo-plastic fluid and an excellent wetting ability to polyester fibers. The ultimate tensile stress and elongation at break for the MWCNTs-PAA coated fiber are 261 MPa and 25.43%. The ultimate tensile stress and the elongation at break are both increasing with the increasing of MWCNTs contents, due to the strong interface bonding ability between the conductive shell and polyester core and strengthen the MWCNTs network. The electrical resistance of the obtained fibers can be controlled in the range from 732 to 30 Ω/cm by changing MWCNTs content, dipping times and annealing temperature. It was found that it is able to light a LED. All results suggest that the conductive fibers embody a good synergy effect of carbon nanotubes and polymers. Therefore, the fabricated conductive fibers have a widely prospect for being applied in the field of flexible electronics.

The CO2solubilities (including CO2Henry's constant) in physical- and chemical-based ILs/DESs and the COSMO-RS models describing these properties were comprehensively collected and summarized. The summarized results indicate that chemical-based ILs/DESs are superior to physical-based ILs/DESs for CO2capture, especially those ILs have functionalized cation and anion, and superbase DESs; some of the superbase DESs have higher CO2solubilities than those of ILs; the best physical- and chemical-based ILs, as well as physical- and chemical-based DESs are [BMIM][BF4] (4.20 mol kg−1), [DETAH][Im] (11.91 mol kg−1), [L-Arg]-Gly 1:6 (4.92 mol kg−1) and TBD-EG 1:4 (12.90 mol kg−1), respectively. Besides the original COSMO-RS mainly providing qualitative predictions, six corrected COSMO-RS models have been proposed to improve the prediction performance based on the experimental data, but only one model is with universal parameters. The newly determined experimental results were further used to verify the perditions of original and corrected COSMO-RS models. The comparison indicates that the original COSMO-RS qualitatively predicts CO2solubility for some but not all ILs/DESs, while the quantitative prediction is incapable at all. The original COSMO-RS is capable to predict CO2Henry's constant qualitatively for both physical-based ILs and DESs, and quantitative prediction is only available for DESs. For the corrected COSMO-RS models, only the model with universal parameters provides quantitative predictions for CO2solubility in physical-based DESs, while other corrected models always show large deviations (> 83%) compared with the experimental CO2Henry's constants.

Obtaining a comprehensive understanding of the energy storage mechanisms, interface compatibility, electrode–electrolyte coupling, and synergistic effects in carefully programmed nanoarchitectural electrodes and complicated electrolyte systems will provide a shortcut for designing better supercapacitors. Here, we report the intrinsic relationships between the electrochemical performances and microstructures or composition of complex nanoarchitectures and formulated electrolytes. We observed that isolated TiNb2O7nanoparticles provided both a Faradaic intercalation contribution and a surface pseudocapacitance. The holey graphenes partitioned by nanoparticles not only fostered the fast transport of both electrons and ions but also provided additional electrical double-layer capacitance. The charge contributions from the diffusion-controlled intercalation process and capacitive behaviors, double-layer charging, and pseudocapacitance, were quantitatively distinguished in different electrolytes including a formulated ionic-liquid mixture, various nanocomposite ionogel electrolytes, and an organic LiPF6electrolyte. A steered molecular dynamics simulation method was used to unveil the underlying principles governing the high-rate capability of holey nanoarchitectures. High energy density and high rate capability in solid-state supercapacitors were achieved using the Faradaic contributions from the lithium-ion insertion process and its surface charge-transfer process in combination with the non-Faradaic contribution from the double-layer effects. The work suggests that practical high-voltage supercapacitors with programmed performances and high safety can be realized viathe efficient coupling between emerging nanoarchitectural electrodes and formulated high-voltage electrolytes.

The formation of hydrogen bonds in the polyethylene terephthalate degradation process is beneficial for the break of ester bonds and accelerates the reaction. Therefore, we designed a series of amino acid ionic liquid catalysts, which have several donor and receptor groups and can form multiple hydrogen bonds with the reactants to enhance the nonmetallic degradation process. By comparing with the traditional catalysts, the designed catalysts avoid the introduction of metal elements and have a similar catalytic efficiency to the traditional metal catalysts. Under the optimal conditions with [Bmim]Pro, the conversion reached 100.0% and the yield of bis(2-hydroxyethyl terephthalate) reached 75.3%. The catalyst has good recycling performance under the reaction condition. Through two-dimensional overhauser enhancement spectroscopy, it was found that there are multiple interactions between [Bmim]Pro and the reactants. Multiple hydrogen bonds between reactants and [Bmim]Pro were proved by density functional theory (DFT) calculations. Finally, the reaction kinetics were studied, which are consistent with the shrinking-core model.

Integrating sustainability principles as a design goal in chemical engineering has become a major challenge facing modern society. This review aims to provide a comprehensive investigation regarding available methods that can potentially be used by industries to quantify the sustainability performance of chemical processes. First, the expansion in the definition of sustainable processes is summarized, forcing corresponding methods to broaden the assessment scope. Then, 30 methods are classified into three categories based on their scope to facilitate their analysis: material and energy flow analysis, life cycle assessment, and sustainability assessment. Key attributes of methods in each category are extracted and discussed in detail. In addition, illustrative examples have been introduced to demonstrate the applicability of these methods. Finally, challenges of the present methods and future research directions for sustainability assessment methods are also highlighted, such that the objective of efficient, environmentally friendly, and economic processes can be realized.

For improving the surface-enhanced Raman scattering (SERS) performance of nanomaterials to achieve trace detection of proteins and complex biological systems, structural and topographical control is one of the important strategies. In this work, a facial and effective method to optimize the topography of TiO2nanotube arrays (TNAs) is demonstrated, together with a significant enhancement of the SERS performance of cytochrome C (Cyt C) on TNAs. An enhancement factor (EF) up to 104, which is obtained with the newly developed method on the basis of the quantification of atomic force microscopy (AFM)-measured interaction force, is achieved, corresponding to a superior detection limit of Cyt C down to 10–7M. The main reason is that adjusting the fluoride contents in an electrolyte (from 0.4 to 0.1 wt %) can reduce the content and sizes of cracks, as well as the tube ruptures of TNAs, where the fluoride content at 0.2 wt % can successfully provide the excellent and optimized topography of TNAs. The TNAs with the optimized topography, especially those with larger tube diameters, demonstrated the importance of structural integrity on a remarkably excellent SERS performance in the trace detection of proteins. The proposed method will stimulate the development and optimization of the active substrate on the SERS applications in biology, bioanalysis, and nanoscience.

The development of biocompatible advanced Fenton-like catalysts with high catalytic activity, good stability, and recyclability using sustainable biosourced materials is of considerable interest yet remains a challenge. Herein, we develop a novel mussel-inspired magnetic cellulose nanocomposite (MCNF/PDA) with carboxylated cellulose nanofibers (CNF) and explore as advanced Fenton-like catalysts to effectively degrade organic dyes and antibiotics. The MCNF/PDA nanocomposites were prepared by anchoring Fe3O4nanoparticles to CNFs via chemical deposition followed with PDA coatings. The composites exhibit an excellent degradation activity toward methylene blue (MB) in a wide pH range of 2–10 in the presence of H2O2and have a maximum degradation capacity of 2265 mg/g. Moreover, the MCNF/PDA nanocatalysts are highly stable and can be easily regenerated. After four cycles, it can still achieve the removal rate as high as 95%. In addition, the MCNF/PDA nanocatalysts also demonstrate an excellent degradation performance to the antibiotic tetracycline. This work provides new insights into fabricating biocompatible cellulosic-based advanced Fenton catalysts with sustainable biomass-derived materials to efficiently remove organic pollutants from wastewater.

Pressure swing adsorption (PSA) is an attractive technology for low-concentration CO2removal from confined spaces. In this study, the dynamic process simulation of PSA with four adsorbents (e.g., Zeolite 13X, carbon molecular sieve (CMS), silica gel, and MOF-508b), the sensitivity analysis, and the minimum energy optimization of the PSA process were employed. The adsorption isotherm Langmuir models of CO2and N2with four absorbents were built, and the estimated values agreed well with the experimental data of the literature. Considering the sensitivity analysis, the minimization of energy consumption of PSA process was conducted to obtain the optimal adsorption pressure, desorption pressure, and purge/feed ratio. The results indicated that Zeolite 13X is the best candidate that meets the separation goals (CO2concentration below 500 ppm) with the lowest specific energy consumption (108.8 kJ·Nm–3N2). The results provide a novel strategy and guidance for low-concentration CO2removal.

To develop catalysts with superior stability for isobutane alkylation, La3+exchanged FAU zeolites with varying framework Si/Al ratios were investigated. Based on the reaction performed in a continuous flow stirred tank reactor, a strong linear relationship between catalyst lifetime and strong Brønsted acid concentration was observed. Catalyst lifetime was speculated to change in an M-shaped pattern with respect to the framework Si/Al ratio, which implies there were at least two extreme Si/Al ratios in terms of catalyst stability. However, their product distribution differed significantly. LaFAU with a high Si/Al ratio led to enhanced acid strength, which resulted in higher cracking, self-alkylation activity, and poor product selectivity. In determining a balance between catalyst stability and product selectivity, a Si/Al ratio of ∼1.2 was selected as the optimal value for LaFAU zeolites.

In this work, metal acetylacetonates were used to catalyze the reaction of dimethyl carbonate (DMC) and bisphenol A (BPA) and high conversion of BPA and excellent selectivity of carboxymethylation products were achieved. Among these, zirconium(IV) acetylacetonate (Zr(acac)4) exhibited the best catalytic performance with BPA conversion of 85.2% and carboxymethylation products selectivity up to 99.0%, which has been the most efficient catalyst so far to the best of our knowledge. According to Fourier transform infrared (FT-IR) characterization and density functional theory (DFT) calculations, we found that the most active cis–cisinteraction species 3 formed between a Zr cation and two oxygen atoms from the CH3–O moiety of DMC greatly promoted the selective occurrence of the carboxymethylation reaction. It was demonstrated that the catalytic performance of metal acetylacetonate was related to d-electrons and interaction mode of the metal, and the plausible reaction mechanism was proposed.

Today, the laws of traditional thermodynamics are facing challenges when science is growing rapidly toward the microscale-world, even quantum hypothesis. In this work, the thermodynamics of nano-confinement and quantum thermodynamics are summarized to illustrate their developments at the microscales.

Nanoparticles resistant to strong acid were prepared by grafting alkyl chains (i.e., C1–, C8–, and C18−) and alkyl sulfonic acid groups onto silica. The composition, morphology, and contact angles of these nanoparticles were characterized. These modified silica nanoparticles were used to fabricate a Pickering emulsion using the mixture of concentrated sulfuric acid and ionic liquid as the water phase and alkane as the oil phase. The effects of nanoparticle structure, ionic liquid concentration, emulsifier content, storage time, and temperature on the physicochemical properties of the emulsion were investigated. It was illustrated that emulsions constructed by C8–SiO2–SO3H (octyl and propylsulfonic acid groups modified silica) were more stable. As the concentration of ionic liquid increased, the droplet size of the emulsion gradually increased. Conversely, the increase of the alkyl chain of the oil phase resulted in a decrease of the droplet size of the emulsion, and no obvious demulsification was observed when the emulsion constructed by C8–SiO2–SO3H was stored at room temperature for 14 days or when the temperature was increased to 80 °C. This kind of emulsion was used to improve the product distribution of isobutene oligomerization under mild conditions. It was found that compared with the system containing no emulsion, the weight percentage of tri-isobutene (C12=) in the product could be enhanced by 4.8% at 40 °C in 60 min, and that of C12=and C16=was increased by 10.5%.