The classic Friedel-Crafts acylation uses acid chloride or anhydride as acylating agents, and Lewis acid as catalysts. The large amount of Lewis acid applied and HCl generated in the acylation reaction must be treated. Acid chlorides are sensitive to moisture, and danger might occur during storage and usage. Acylation using carboxylic acids in the presence of trifluoroacetic anhydride as acylating agents does not require conversion of the acylating agents into acid chloride, anhydride or amide. Furthermore, the trifluoroacetic anhydride and trifluoroacetic acid generated can be easily recovered by distillation. Therefore, it can effectively solve the problems associated with the classic Friedel-Crafts acylation. This review summarizes the developments of the acylation process using carboxylic acids in the presence of trifluoroacetic anhydride as acylating agents, and their applications in the syntheses of organic functional molecules, drug molecules and natural products during the last two decades.

“Coordination space” is the space with specific structure and functions, which is defined by the coordination bonded structural elements of inorganic-organic hybrid system. This concept provides a new perspective for the research on the targeted construction and modulation of coordinative hybrid materials. As typical inorganic-organic hybrid materials, Metal-Organic Framework (MOF) and Metal-Organic Cage (MOC) have attracted widespread attention in recent years. The key point of targeted construction and regulation of could be regarded as the design of their coordination space. The stimuli-responsive MOFs possess dynamic coordination space, which promote their potential applications in adsorption/separation, sensing, drug delivery, and related fields. Based on the well-developed research of dynamic of metal-organic framework, herein we briefly introduce the recent progress in dynamic coordinate space, including the structure foundation and stimulating factors for the achievement of dynamic behaviors, the relationship between the structure and properties of this kind of material, which could be instructive useful references for related research investigation.

Diphenylalanine dipeptide is a key recognition sequence of the β-amyloid protein that causes Alzheimer's disease. Due to its simple structure and excellent assembly performance, diphenylalanine dipeptide has been becoming a “star” building block in the field of molecular assembly to construct many functional materials. At present, a large number of researchers have been carried out on the controllable assembly of diphenylalanine dipeptide and its derivatives, including molecular design, structural regulation and functional applications. In recent years, through molecular assembly, our group has achieved the controlled preparation of diphenylalanine dipeptide-based assemblies by modulating various kinds of molecular interactions including Schiff-base covalent bonding, electrostatic attraction, hydrogen bonding and pi-pi stacking. In particular, we have explored optical properties and potential applications of such assembled diphenylalanine dipeptide-based materials. This review will mainly introduce the research progress mentioned above. Firstly, the preparation methods of diphenylalanine-based photofunctional materials through covalent, non-covalent or combined assembly are analyzed, compared and discussed. Then, the applications of these assembled materials in actively optical waveguiding, optical imaging for tracing drug delivery, photodynamic therapy for cancer treatment, patterned photofabrication and biomimetic photocatalysis are introduced in detail, respectively. Finally, we give a summary and propose the possible development trend of diphenylalanine dipeptide-based assemblies.

Hydrogen (H₂) gas acquires a high combustion calorific value (285.8 kJ/mol) and only produces water during combustion, so it is considered as an ideal energy carrier. Photocatalytic H₂ evolution from water by simulating the structure and function of active center in natural photosynthesis is not only an important way to convert solar light into chemical energy but also an essential part of artificial photosynthesis. Here, we summarize the recent major progress of this field and forecast the development and potential applications of artificial photosynthetic H₂ production in the near future.

Carbon clusters, a new type of carbon material, have attracted great attentions in scientific community due to the unique structures and superior performances since its discovery in the 1980s. Carbon clusters have a wide range of categories ranging from single carbon atom in the gas phase to fullerenes, carbon nanotubes, carbon nanocones, graphenes, etc. It is of great significance to study the structures and progress of carbon clusters and solve the mystery of the formation mechanism for exploring new structures and applications of carbon cluster materials. In this paper, we review the structures and progress of carbon clusters and summary the synthesis, characterization and current state of progress of carbon clusters.

Inspired by the highly efficient biological motors in nature, researchers proposed the concept of micro/nanomotors, or micro/nanoscale autonomously moving devices. Combining the technology of chemistry, physics and multidisciplines, various micro/nanomotors of different structures, motion mechanisms and control methods are fabricated. These micro/nanomotors demonstrate great promises in multiple fields including sensing, environment remediation, biomedicine, etc. One of the most important applications in biomedicine is drug delivery. The micro/nanomotors can achieve efficient drug delivery, shedding new light for conventional cancer therapy. In this review, we focus on micro/nanomotors for drug delivery and introduce their structures, mechanisms and control methods. The motion mechanisms(self field mechanism and external field mechanism) of micro/nanomotors will be covered. Motor structures(polymer vesicle, tube and nanowire) suitable for drug delivery will be introduced. For efficient targeted drug delivery, motion control is very important. The on-off control, direction control and velocity control will be discussed. Current bottlenecks are also summarized and possible future direction of the field is discussed.

Long-chain aliphatic dicarboxylic acids generally refer to the saturated straight-chain dicarboxylic acids containing ten or more carbon atoms. Due to the existence of carboxyl functional groups in each terminal, they are usually applied to synthesize perfumes, special nylon engineering plastics, hot melt adhesives, coatings, plasticizers, senior lubricants and many other chemical products. In addition, they have better properties than short-chain dicarboxylic acids because of their long methylene sequences, which makes the corresponding composite materials have superior performance and be widely used in chemical industry, light industry, national defense, automobile industry, engineering materials and other fields. Besides, they could be also used to develop new polymer products. Long-chain aliphatic dicarboxylic acids do not exist alone in nature. At present, they have been synthesized mainly via chemical synthesis and biological fermentation in industry. In this review, the synthetic methods of long-chain aliphatic dicarboxylic acids are summarized, including traditional organic synthesis, biotechnology conversion, olefin metathesis, isomerization hydroxycarbonylation and functionalization of polyethylene. The application of long-chain aliphatic dicarboxylic acids in the polycondensation(mainly of polyesters and polyamides) is also briefly introduced. Finally, the problems remaining to be solved in the synthesis and the further advances are prospected.

Peptides self-assembly has great potential applications in the field of biomedicine and construction of new materials for the advantages of stable structure, easy control, and good biocompatibility and biodegradability. In this paper, the progress in peptides self-assembly is systematically reviewed, including the conception, mechanism and applications, focusing on the stimuli-responsive peptides self-assembly. According to the difference of stimuli, stimuli-responsive peptides self-assembly can be classified into pH-responsive self-assembly, temperature-responsive self-assembly, solvent-responsive self-assembly, light-responsive self-assembly, ultrasonic responsive self-assembly, and ion-responsive self-assembly. The applications of peptides self-assembly in drug release carriers, the repair of spinal cord injury, biomimetic enzyme catalysis, and biological template are listed in detail. Finally, the problems of peptides self-assembly research, such as difficult control of the external factors that affect the structure of assembly and the low degree of overlap between peptides self-assembly and life sciences, are analyzed, and the future development of stimuli-responsive peptides self-assembly is prospected.

As one of the most promising analytical instruments, mass spectrometry(MS) technology has shown a broad application prospect in medicine, food, environment, human health, national security and other related fields. While the different types of analytes have diverse characteristics and largely add the difficulties of direct ionization and mass spectrometric analysis. Ambient mass spectrometry(AMS) is a kind of newly emerging technology performed under ambient conditions that allows the direct analysis of sample or sample surfaces with little or no sample pretreatment. The development and applications of ambient ionization mass spectrometry(AI-MS) that realized ionization under ambient conditions without sample pretreatment have become a frontier field in mass spectrometry and deserved much attention over the last few years. Ambient ionization has high sensitivity and specificity. It also can rapidly analysis real-time in situ and achieve high-throughput analysis without destructing the sample. As a soft ionization method, ESI offers unique advantages for proteomics by allowing the direct analysis of thermolabile compounds and forming multiply charged ions. The developments and applications of mass spectrometry imaging(MSI) have become a frontier field in mass spectrometry and molecular imaging. Some recent contributions on the development of ambient ionization can be applied to mass spectrometry imaging. This review focuses on the development of ionization mechanism, characteristics and applications of various ion sources, which are based on electrospray ionization (ESI) principle.

Organosilicon materials as a novel class of functional materials with unique properties have become one of the most important research fields in chemistry and material sciences. The present review summarizes novel synthetic methodologies, including alkynyl-azide cycloaddition reaction, thiol-ene reaction and amine-ene Michael addition reaction, for organosilicon synthesis. In particular, the advantages of these strategies and their applications in novel functional organosilicon compounds, organosilicon polymers and organosilicon elastomers are introduced. Finally, the trend and future prospects of novel synthetic strategies for organosilicon synthesis will be presented.

The compounds with aggregation-induced emission (AIE) property have been widely developed to solve aggregation-caused quenching (ACQ) problem of organic luminophores at high concentration, in the solid state, or in the form of thin film. Therefore, AIE compounds are useful for a number of applications, such as fluorescent probes and receptors, and cell imaging. Tetraphenylethene (TPE) and its derivatives, as typical compounds with AIE property, have been widely applied in materials chemistry, biochemistry, and other related fields. Inspired from AIE, TPE has been also introduced into the field of supramolecular chemistry by supramolecular chemists. Especially, given their ability to restrict the intramolecular rotation or motion of TPE molecules, macrocyclic hosts can form host-guest complexes or supramolecular polymers with TPE via host-guest interactions, which results in enhancement in the AIE effect of guests. Hence, AIE of TPE derivatives with macrocycles via host-guest interaction also provides a new approach to develop the applications in stimuli-responsive sensors and probes. This review mainly focuses on summarizing the research progress of host-guest complexes between macrocycles and TPE, and comments on the bright future of AIE behaviors of the supramolecular systems involving host-guest interactions.

Water resource is a prerequisite for the survival of human beings with a self-evident importance. In recent years, water environment continues to deteriorate and water pollution is becoming more and more severe, oil spillages and indiscriminate discharge of organic pollutants cause serious and irrecoverable damages to environment and ecosystems, and the way for effective separation of oil-water mixture is becoming an urgent problem. The frequently-used methods for oil/water separation are physical adsorption, chemical dispersion and biodegradation, in which chemical adsorption and biodegradation methods usually cause secondary pollution to the marine environment; and the physical adsorption material has the advantages of easily collection, pollution-free and so on. This article summarizes the research status of physical filtration and physical adsorption materials for oil/water separation, some related difficulties that remain to be solved are pointed out and its future researching focus and developing directions are proposed.

Superhydrophilic-superoleophobic oil/water separation membrane is a special membrane for water penetration and oil retention in separation process, which has advantage of antifouling by oil when dealing with off-shore oil spillages and oil-polluted water. This kind of membrane is very meaningful in practical application. In order to grasp recent development in superhydrophilic-superoleophobic oil/water separation membrane, firstly, the mechanism of oil/water separation is described based on the hydrostatic pressure and capillary force. Then, the preparation and properties research of superhydrophilic and superoleophobic metal-based membrane, stimulus-responsive polymeric membranes and substrate-free polymeric membrane for oil/water separation are comprehensively reviewed. Finally we summarize the current problems in the field of superhydrophilic-superoleophobic oil/water separation membrane and prospect the future development.

The shortage of oil resources and the need to reduce the environmental burden caused by petroleum-based polymers have driven the development and production of biodegradable materials. In recent decades, natural polymers have replaced current synthetic polymers due to their non-toxicity, biodegradability, and biocompatibility. Starch has been extensively studied for the manufacture of biodegradable composites due to its reproducibility, biodegradability, low cost, and availability, which has been widely used for applications in agriculture, alimentary, medicine and packaging industry. However, the polyhydroxyl structure of starch gives it strong hydrophilicity, and the moisture sensitivity limits their mechanical properties and affects their application. In this paper, mainly from the perspective of improving the physical and chemical effects of thermoplastic starch, the research works in recent years on improving the water resistance of thermoplastic starch material and reducing its sensitivity to environmental humidity are summarized. The related factors affecting the water resistance and the methods of improvement are introduced, and the research trend in this field is also proposed.

Bisphenol A (BPA) is a phenol derivative and widely used in the manufacture of polycarbonate plastics and epoxy resins. It is one of the largest industrial products in the world. The extensive use of BPA makes it more easily exposed to the general population. BPA is believed to be a typical estrogen-like endocrine disruptor that can induce multiple toxic effects on the human body. High-dose BPA exerts its endocrine-disrupting effects mainly by antagonizing estrogen receptors (ERs); environmentally-relevant low-dose BPA cannot compete with estrogen for binding to ERs, and induces biological effects in a non-genomic manner mainly through the membrane receptor-mediated signaling pathways. However, it is still unclear which membrane receptor mediates the low-dose effect of BPA and the related molecular mechanisms. Based on this, our laboratory has done a series of work in these areas in recent years. We have found that membrane G protein-coupled receptor 30 and integrin αvβ3 and their mediated signaling pathways mediate the effects of environmentally-relevant low-dose BPA on the induction of male germ cells proliferation and the transcription of thyroid hormone genes, respectively. An in-depth understanding of the molecular mechanism of environmentally-relevant low-dose BPA will contribute to a more objective and realistic evaluation and prediction of the potential effects of environmental exposure on human health and then perform targeted prevention and interventions. Likewise, it will also provide a theoretical basis and technical support for evaluating the health effects of endocrine disruptors in other similar structural estrogen-like environments. This article combines our research work in recent years, reviews the current progress in the molecular mechanism of environmental low-dose BPA exposure on human health, existing problems, and some future research.

This review summarizes the recent advances of semi-volatile/intermediate volatility organic compounds studies, including the measurement techniques, S/IVOCs sources, atmospheric behavior and their contributions to organic aerosol formation. The rapid development of mass spectrometry facilitates the S/IVOCs measurements which include on-line and off-line mass spectrometry. The S/IVOCs off-line measurements provide more information about species at molecular level. However, the offline techniques bear the drawbacks of complex pretreatment and low time resolution, which leads to large uncertainties and the limitation to study the atmospheric chemistry processes. The on-line techniques measure the high time resolution molecular composition and gas-to-particle partitioning, and provide more useful information to elucidate the chemical mechanism of the ambient atmosphere. S/IVOCs could be directly emitted into the atmosphere, or formed by the oxidation of volatile organic compounds (VOCs). The major primary S/IVOCs sources are vehicular emission and biomass burning. Previous studies showed that ratios of S/IVOCs to POA are 2.9~8.5 for gasoline engines, 4.5~20.4 for diesel engines, and 0.83~5.57 for biomass burning. The S/IVOCs oxidation could contribute to 34%~76%, 90%, and 80% of the total SOA from the oxidation of gasoline vehicle exhaust, diesel vehicle exhaust, and biomass burning gases, respectively. Model simulation based on field observations showed that the SOA from the S/IVOCs oxidation could account for 40%~85% of the ambient SOA, suggesting that S/IVOCs are unneglectable SOA precursors. In future studies, new techniques are required to be developed to quantify more S/IVOCs species. Concentrations and speciation of S/IVOCs from different sources as well as ambient atmosphere need to be quantified. The combination of field campaign, lab study and model simulation can provide more insights of mechanism of S/IVOCs oxidation to improve our understanding of SOA formation.

Food safety has received great attention due to its close connectivity with people’s health and the harmonious development of national economy and society. Trace amount of toxic and harmful compounds in food and water are potentially harmful to human health. Excellent adsorbent and efficient extraction have received more and more attention in food safety detection. Metal-organic frameworks (MOFs) are an emerging class of porous functional materials with high porosity, large surface area, easy structural design, adjustable pore size, as well as acceptable chemical and thermal stability. In the past, the research on MOFs mainly focused on the structural design. Recently, more and more attention has been focused on applications of MOFs in food safety analysis. Meanwhile, their high porosity, tunable surface functionalities, various metal and ligands, as well as diverse coordination modes make MOFs promising as adsorption material for SPE. The merits of MOFs and their functional materials, in particular, are high enrichment, excellent matrix interference resistance, good selectivity, and environmentally-friendly development. Interesting research of MOFs and their functional materials in the pretreatment of food and water samples are summarized.

Silicon is expected to replace graphite as the next-generation anode material for lithium-ion batteries because of its high theoretical specific capacity. But the huge volume expansion (~300%) of silicon during lithiation/delithiation process will cause active substance pulverization and loss contact with current collector, and continuous formation of solid electrolyte layer will further result in irreversible capacity fading. It has been demonstrated that nanocrystallization and carbon coating are effective ways to overcome these problems. In this paper, the mechanism of capacity fading of silicon is introduced, and the latest research on the synthesis of Si nanoparticles and carbon composites is reviewed, mainly including coating, core-shell and embeded silicon/carbon anode materials. The core-shell and embedded type are specifically reviewed. Finally the problems of the Si nanoparticles/carbon composites are analyzed and the prospects for research are prospected.

Due to the low cost and high safety of the new sodium battery system using sodium-based solid electrolyte, the new sodium battery system has great potential for its applications in energy storage field. High ionic conductivity and stability of sodium-based solid electrolytes are prerequisites for its applications in new sodium battery systems. In recent years, people have significantly improved the ionic conductivity and stability of sodium-based solid electrolytes by improving preparation methods and doping modifications. In addition, the new sodium battery system needs to solve the interface problems such as poor interface contact and poor interface stability between the solid state electrolyte and the electrode. In this paper, we firstly summarize the research progress in ionic conductivity and stability of β″-Al₂O₃, NASICON, sulfides, and polymer of sodium-based solid electrolytes. Then the applications of sodium-based solid electrolytes in sodium-sulfur batteries, hybrid sodium-air batteries, and all-solid-state sodium-ion batteries are introduced. In view of the interface problems, the solving strategies are systematically discussed. The future large-scale applications in energy of the new sodium battery system based on solid state electrolytes need breakthroughs in many aspects such as battery materials, interfaces, and battery design.