Multicomponent reactions (MCRs) are those reactions which incorporate three or more starting materials in one pot and prepare the final products effectively and efficiently. During multicomponent reactions, nearly all atoms from reactants contribute to the final product. Also, such reactions are free from lengthy intermediate separation and purification, so they have been widely used to synthesize complicated molecules such as drug precursors, bioactive molecules and so on. Our group has developed a unique system to carry out MCRs on the polymerization platform, combining monomer preparation and in situ controlled polymerization together in one-pot style, thus generating multifunctional polymers in one-step. The reactions involved in this system cooperated well without interference, thus generating well-defined products with controlled molecular weight and narrow polydispersity index(PDI). Compared with traditional multifunctional polymer synthesis techniques (step-by-step or post-modification approaches), this one-pot system has many intrinsic advantages: time-saving, atom-economic, green and highly efficient. By now, we have successfully developed several multicomponent polymerization systems, including binary, ternary and even quaternary systems. Meanwhile, the further applications of these systems have been investigated as well. We have demonstrated that chiral polymers and gradient polymers, which are difficult to be synthesized through orthodox approaches, could be easily and effectively prepared in these systems. With more investigation and understanding about this one-pot multicomponent polymerization system, we believe that it could be a facile and versatile alternative methodology for multifunctional polymer synthesis and preparation in the near future.

Contents
1 Introduction
2 Multicomponent one-pot polymerization and functionalization system
2.1 Binary system
2.2 Ternary system
2.3 Quaternary system
3 Applications of multicomponent one-pot polymerization and functionalization system
4 Conclusion and outlook

Self-assembly of nanoparticles at interfaces has become the focus of extensive studies since the phenomenon of Pickering emulsion, known as a fact that solid particles can spontaneously migrate onto fluid/fluid interface forming monolayer or multilayer, acting as the "surfactant" to stabilize the emulsion, was firstly established in early 20th century. Using interface, especially fluid/fluid interface, to guide the directed assemblies of nanoparticles is of great scientific interest for the food, cosmetics and pharmaceutical industry. For liquid/liquid interface-induced assembly, reduction of the interfacial energy is the dominating driving force. Self-assembly processes can be controlled by tuning the sizes of the nanoparticles as well as the chemical characteristics of the ligands on the particle surfaces. In this review, self-assembly behavior of different types of nanoparticles, including homogeneous, Janus-type, rod-type, and biological nanoparticles, and their applications are summarized. All these studies have shed new light on the basic understandings of self-assembly of nanoparticles at interfaces and widened the application fields of nanoparticles. The hierarchically ordered structures generated by self-assembly of nanoparticles could find extensive applications in various fields, such as optics, acoustics, electricity, magnetics, medicine, etc. Furthermore, the limitation and future development in the field of self-assembly of nanoparticles at interfaces are elucidated.

Contents
1 Introduction
1.1 Pickering emulsion
1.2 Nanoparticles as building block
2 Self-assembly of nanoparticles at interface
2.1 Homogeneous nanoparticles
2.2 Janus nanoparticles
2.3 Rod-type nanoparticles
2.4 Biological nanoparticles
3 Conclusion and outlook

This review summarizes the preparation methods of mixed-phase TiO₂ photocatalysts. Two main lines of fabrication have been followed: one is preparation of mixed-phase TiO₂ in situ (e. g. hydrothermal method, solvothermal method, sol-gel method and microemulsion-mediated hydrothermal method, etc.), and the other is physical mixing of different phases of TiO₂ or calcinations under high temperature (e. g. solvent mixing and calcination treatment, calcination under high temperature, etc.). The latter has fewer requirements on the equipments, but the produced TiO₂ nanoparticles tend to be aggregates, which affects the photocatalytic performance of TiO₂ materials seriously. The former has more advantages in practical applications. At the same time, this review summarizes and remarks the researches on photocatalytic mechanisms of the mixed-phase TiO₂. Furthermore, the applications of the mixed-phase TiO₂ photocatalysts in environmental and energy fields are also prospected.

Contents
1 Introduction
2 Synthesis of the mixed-phase TiO₂ photocatalysts
2.1 Phases of TiO₂
2.2 Methods of preparing the mixed-phase TiO₂ photocatalysts and their influencing factors
3 Mechanisms of the enhanced photocatalytic activities by the mixed-phase TiO₂ photocatalysts
4 Conclusion and outlook

Mesoporous metal-organic frameworks(MOFs), comparing with those with micropores, have attracted tremendous attention for expanding their applications in gas storage, heterogeneous catalysis, volatile organic compounds (VOCs) adsorption, drug carrier, etc. Metal-organic frameworks are still largely restricted to the microporous regins to date, with the negative impact of small pore size on the diffusion and mass transfer inside. The development of reliable and reproducible methods to prepare and stabilize mesoporous metal-organic frameworks with tailored structures and tunable properties remains a great challenge to meet many future applications. The structure of materials can be designed on molecular level, but the problem remains that the frameworks tend to interpenetrate one another to maximize packing efficiency or collapse while solvent molecules removed. The preparation and applications of mesoporous metal-organic frameworks are reviewed in this paper. Several preparation approaches, such as combining secondary building units(SBUs) and extended ligands, designing zinc-adeninate octahedral building units with lager size, using long ligands or mixed-ligands, surfactant template to get mesosize channels, cages or pockets are presented in detail, and the advantages and disadvantages of each method are summarized. In addition, applications of mesoporous metal-organic frameworks in the areas of gas storage, catalysis, sensors, adsorption of VOCs and drug carrier are introduced.

Contents
1 Introduction
2 Design of mesoporous metal-organic frameworks
2.1 SBU and extended ligands
2.2 Metal-adeninate vertices
2.3 Long ligands
2.4 Utility of mixed-ligands
2.5 Surfactant template
3 Application of mesoporous metal-organic frameworks
3.1 Gas storage
3.2 Heterogeneous catalysis
3.3 Sensors
3.4 Adsorption of VOCs
3.5 Drug carrier
4 Conclusion

Surface plasmon resonance (SPR) biosensor technology, with countless researches and attractive progress, has been commonly applied in the field of biochemical analysis. From theoretical research to design and produce of bioanalytical instrument, application development and performance improvement, our research team has been engaged in SPR study for almost 10 years and always concerned about the latest progress. This paper mainly includes: the description of principle, components and accessories of SPR bioanalytical instrument, modulation types and coupling configurations of SPR sensor, as well as SPR imaging sensor; the methods for improving the bioanalytical instrument performance, namely, the combination with local surface plasmon resonance (LSPR) technology, metal film redesign and data processing optimization; the lasted developments, involving the technology combination between the SPR and microfluidic chip, electrochemistry, surface-enhanced raman scattering (SERS); the applications in clinical diagnosis, drugscreening, human biomolecular research, food safety and environmental monitoring; and the main problems and future trends of SPR bioanalytical instrument.

Contents
1 Introduction
2 SPR bioanalytical instrument
2.1 Principle of SPR
2.2 SPR instrument
3 SPR sensors
3.1 Modulation types
3.2 Coupling configurations
3.3 SPR imaging sensors
4 Performance improvement mothods of SPR biosensors
4.1 Local surface plasmon resonance
4.2 Metal film
4.3 Data processing
5 The developments of SPR biosensors
5.1 SPR combined with microfluidic chip
5.2 SPR combined with electrochemical
5.3 SPR combined with SERS
6 Applications
7 Conclusions and prospects

The study of polymer materials with stimulation responsibility has been one of the current cores in polymer research. Serving as an innovative stimulating source, mechanical force owns several properties different from traditional sources such as light and heat. Mechanical forces can be divided into two categories from their origins, i.e. the microscopic mechanical force and the macroscopic one. Mechanical force at macroscopic level has long been utilized to process and mold polymer materials even since ancient time of human history. However, the principles and applications of microscopic mechanical force responsive polymer has not been focused on until the past decades. In this review, we start from the analysis of the mechanochemical principles, followed by the exhibition of various mechanical force responsive systems divided into different groups. Specially, according to the bonds responsively broken by mechanical force, we divided them into covalent bond system and non-covalent bond system. The covalent bond systems can be further separated into cyclic structure systems and linear ones. Additionally, this article has provided a window into the existing interdisciplinary applications, including mechanical force stimulated racemic isolation, mechanical force stimulated catalyst activation, mechanical force assisted mechanism study, and so on. We hope the review can have the potential to offer some meaningful points to the en route development of mechanochemical systems and their further applications.

Contents
1 Introduction
2 General principles of mechanical force responsive polymer systems
3 Catalogs of mechanical force responsive polymer systems in polymer chemistry
3.1 Covalent bond systems
3.2 Non-covalent bond systems
4 Applications
4.1 Mechanical force stimulated racemic isolation
4.2 Mechanical force stimulated catalyst activation
4.3 Active species generation from mechanical force stimulation
4.4 Mechanical force assisted mechanism study
5 Conclusion and outlook

Gellan gum is an anionic linear microbial polysaccharide. It has been extensively used in foods and cosmetics industries due to its special gelling property and rheological behavior of its aqueous solution since the early stage of its discovery. Recently, gellan gum as a natural polymer and its hydrogel show a wide range of application perspective in drug delivery and tissue engineering. Gellan gum is nontoxic, biocompatible, biodegradable and the resulting hydrogel is transparent and stable. The mechanical properties of gellan gum hydrogel are similar to those of normal human tissues under certain conditions. These advantages provide gellan gum versatile characteristics as a source of biomaterials. However, gellan gum-based hydrogels have intrinsic disadvantages such as lack of toughness and tissue tolerance as tissue engineering materials. These defects restrict their use in biomedical field. In order to solve these problems, quite a lot of work on chemical and physical modification on gellan gum has been carried out. Modified gellan gum reveals a much more promising perspective in the development of biomedical materials. In this paper, we summarize the gelation mechanism of gellan gum and various modification methods, and highlight the application of gellan gum and modified gellan gum based hydrogels in biomedical field. We also point out a number of main challenges for gellan gum-based tissue engineering materials.

Contents
1 Introduction
2 Structure and properties of gellan gum
2.1 Chemical structure and conformation
2.2 Rheological property of aqueous gellan gum solution
2.3 Gelation mechnism of gellan gum hydrogels
3 Chemical/physical modifications of gellan gum and their effect
3.1 Derivatization
3.2 Hydrophobization
3.3 Crosslinking
3.4 Graft copolymerization
3.5 Dual interpenetrating network
3.6 Compound modification
4 Applications of gellan gum and its modified materials in biomedicine
4.1 Drug controlled release
4.2 Tissue engineering
4.3 Other biological applications
5 Outlook

Polymeric cryogel with interconnected pore structure can be prepared using the cryogelation technique and have been paid intensive attention in the fields of both academia and industry. Because of its high porosity, permeability, and chemical/mechanical stability, polymeric cryogel has been widely used as stationary phase in chromatography separation of particulate-containing fluids and cells, carriers for immobilization of cell/biological particulates, and three-dimensional scaffolds for tissue engineering. This paper introduces in detail the preparation of polymeric cryogel and relationship between its structural parameters and preparation process, such as concentration of monomer/precursor/initiator, freezing process, and solvent. The functionalization of cryogels as well as its biomedical applications are also summarized.

Contents
1 Introduction
1.1 Preparation and structure of polymeric cryogels
1.2 Pore structure and the preparation process
1.3 Structure characterization of cryogels
2 Functionalization of polymeric cryogels
2.1 Copolymerization of functional monomers
2.2 Surface coupling of functional groups
2.3 Surface graft polymerization
2.4 Double crosslinking
2.5 Composite cryogels
3 Application of polymeric cryogels
3.1 Stationary phase in chromatography separation of cell/biological particulate
3.2 Carrier for immobilization of cell/biological particulate
3.3 Scaffold for tissue engineering
4 Conclusion and outlook

Frontal polymerization (FP) is a synthesis process in which a localized reaction propagates directionally through the reactor. Compared with batch polymerization, FP is a simple, quick, energy-saving way to produce polymerization materials with distinctive properties. It is a new promising method for preparing functional materials and structural materials. In this paper, research progress on the reaction system, ignition, process, application and problems of FP are summarized. Some achievements of frontal polymerization in recent ten years are reviewed emphatically. Besides the free radical polymerization, there are more and more new frontal polymerization systems, such as binary-phase and multi-phase systems, ionic liquid monomer systems and deep eutectic solvents systems. More and more assistant agents, such as fillers, cross-linking agents, chain transfer agents, activators, thickening agents, surfactants and catalysts, are added to frontal polymerization and play an important role on the polymerization process and structure and property of polymers. New initiators, such as photo-initiators, ionic liquid initiators and other specially designed initiators, are described here. New initiation modes, such as UV, water, plasma and coupling ignition, are also discussed. Two new special processes of frontal polymerization are included. At last, the problems of frontal polymerization and the research area of commercializing the frontal polymerization are proposed.

Contents
1 Introduction
2 Advantages of FP
3 Reaction system
3.1 Monomer
3.2 Initiator
3.3 Solvent
3.4 Assistants
4 Initiation of FP
4.1 Heat
4.2 UV
4.3 Others: plasma, laser,magnet,water
5 Process of FP
5.1 Process parameters
5.2 Process monitor
5.3 Special Processes
6 Application of FP
6.1 Preparation of SAP
6.2 Preparation of hydrogel
6.3 Preparation of porous materials
6.4 Preparation of environmental materials
6.5 Preparation of nanophase materials
6.6 Preparation of hybrid materials
6.7 Preparation of amphiphilic materials
6.8 Epoxy curing
6.9 Preparation of functional gradient materials
6.10 Preparation of interpenetrating polymer network
6.11 Preparation of photoelectric materials
7 Problem of FP
8 Conclusion

Hydrogels are a class of hydrophilic, crosslinked polymeric materials. They are valuable for drug delivery, biosensing and tissue engineering. Generally, hydrogels with nearly ideal network structures can be obtained via the click reactions which have advantages of fast reaction rate, modularity and less by-products. As the representative of click chemistry, Cu(Ⅰ)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction has been applied widely for the preparation of hydrogel materials. The copper metal contamination in the obtained hydrogels is a major concern because of the use of copper salts catalytic system. The drawback counteracts the applications of CuAAC reaction in the fields of synthesis of hydrogels. Copper-free click reactions, such as thiol-ene/yne reaction, furan/anthracene-maleimide (MI) Diels-Alder (D-A) reaction and strain-promoted alkyne-azide cycloaddition (SPAAC) reaction, have been widely used to prepare hydrogel materials. In this paper, the application of the copper-free click reaction in preparing the hydrogels and their functionalization are reviewed. In addition, the trend of their development is discussed.

Contents
1 Introduction
2 Synthesis of hydrogels via Cu-free click chemistry
2.1 Synthesis of hydrogels via thiol-ene click reaction
2.2 Synthesis of hydrogels via Diels-Alder click reaction
2.3 Synthesis of hydrogels via Cu-free azide-alkyne cycloaddition reaction
3 Outlook

The ever-increasing demand for energy and environmental resources is both an opportunity and a severe challenge for the development of energy storage batteries. Nano-carbon materials such as carbon nanotubes and graphene are widely used in the electrode technology of energy storage batteries because of their many useful properties, including high electrical conductivity, outstanding mechanical strength, and unique morphology and structure characteristics. This paper provides an overview about the most recent progress in the applications of carbon nanotubes and graphene (e. g., composite electrode materials, anode active materials and conductive additives in lithium ion batteries, as well as composite conductive matrices in novel Li-S batteries). The electrochemical performance of the batteries affected by their different application modes in terms of lithium storage capability, rate capacity and cycle life are highlighted. Discussions on challenges and perspectives of these carbon materials in this exciting field such as exploring low cost and environmental friendly synthesis techniques for high-quality materials, improving the dispersion technology for efficient design of hybrid nanostructured materials and seeking for new application modes are also presented.

Contents
1 Introduction
2 Used as composite electrode materials in lithium-ion batteries
2.1 Carbon nanotubes based composite electrode materials
2.2 Graphene based composite electrode materials
3 Used as anode active materials in lithium-ion batteries
3.1 Carbon nanotubes as anode active materials
3.2 Graphene based materials as anode active materials
4 Used as conductive additives in lithium-ion batteries
5 Used as composite conductive matrices in novel Li-S batteries
5.1 Carbon nanotubes/sulfur composites
5.2 Graphene based materials/sulfur composites
6 Conclusion and outlook

Many researchers focus on the microbial fuel cells (MFCs) treating wastewater, due to their distinguished advantages of water purification as well as recovering energy or valuable chemicals. In microbial fuel cells, metal ions play an important role in the conductivity of solution, reactor resistance, power density, electricity production and activity of microorganism. Additionally, the metal ions are also involved into the anode or cathode reaction processes directly or indirectly in the MFCs. The mechanism of MFCs process participated with several metal ions and their influence factors are reviewed in this paper. Moreover, we discuss the advantages and development prospects of the MFCs removing heavy metal ions in wastewater or solid waste.

Contents
1 Introduction
2 Effect of inert metal salts on electrolyte conductivity and on internal resistance for MFCs
3 Effect of metal ions on anodic behavior
3.1 Effect of Ca²⁺ on anodic behavior
3.2 Effect of Fe³⁺ on anodic behavior
3.3 Effect of V⁵⁺ on anodic behavior
3.4 Effect of Mn⁴⁺/Mn²⁺ on anodic behavior
3.5 Effect of Pd²⁺,Au³⁺ on anodic behavior
3.6 Modified anode by other metal ions
3.7 Detection of heavy metal toxicity
4 Effect of metal ions on cathode behavior
4.1 Cu²⁺ used as cathode electron acceptor
4.2 Cr⁶⁺ used as cathode electron acceptor
4.3 Ag⁺ used as cathode electron acceptor
4.4 Effect of Fe³⁺/Fe²⁺ on cathodic behavior
4.5 Other metal ions used as cathode electron acceptor
4.6 Various metal ions used as cathode electron acceptor
4.7 Effects of modified cathode by transition metal ions on the cathode behavior
5 Perspectives

Dye-sensitized solar cells (DSC) play a leading role in the third generation photovoltaic devices due to their low cost, easy fabrication process, high conversion efficiency, and good stability. As a media of dye adsorption, electron transport, and electrolyte diffusion, the nanocrystalline semiconductor photoanode plays a key role during light-to-electricity conversion in DSC. Apparently, titania (TiO₂) has been most frequently used as a photoanode materials in DSCs. Although other semiconductors such as ZnO, SnO₂, and SrTiO₃ etc. have also been widely applied in photoanode of DSC, none of them have shown better performance than TiO₂. Up to now, a record efficiency of 12.3% for the DSC with TiO₂ photoanode has been achieved. However, further improvement of the conversion efficiency of DSC is still a major issue for its application prospects. In recent years, doping TiO₂ with metal and nonmetal elements has been considered as a promising way to tailor the electronic properties of TiO₂ photoanode in DSC and has succeeded in improving photovoltaic performance of DSC. This article presents an overview on doped nanocrystalline TiO₂, including non-metal doped TiO₂, transition metal doped TiO₂, rare earth doped TiO₂, and main-group metal doped TiO₂ employed as the photoanode for improving photovoltaic performance of DSC. The influence of foreign-elements doping on the band edge, the trap state distribution, the electron transport process, the recombination reaction, and the light harvesting of TiO₂ photoanode are discussed. Lastly, an outlook on the future challenges and prospects of doped nanocrystalline TiO₂ materials as the photoanode for DSC are also briefly brought up.

Contents
1 Introduction
2 Nonmetal-doped TiO₂ photoanode of DSC
2.1 N-doped TiO₂ photoanode of DSC
2.2 Halogen-doped TiO₂ photoanode of DSC
2.3 B-doped TiO₂ photoanode of DSC
2.4 Codoped TiO₂ photoanode of DSC
3 Transition metal doped TiO₂ photoanode of DSC
3.1 Zn-doped TiO₂ photoanode of DSC
3.2 Cr-doped TiO₂ photoanode of DSC
3.3 W-doped photoanode of DSC
3.4 Nb-doped photoanode of DSC
3.5 Ta-doped TiO₂ photoanode of DSC
4 Rare earth doped TiO₂ photoanode of DSC
5 Main-group metal doped TiO₂ photoanode of DSC
6 Conclusion and outlook

Perfluorooctanoate and perfluoroctanesulfonate (PFOX) are environmentally persistent, recalcitrant to oxidation, and resistant to conventional chemical treatments. The related studies on the exploration and establishment of the effective removal techniques for PFOX have become the new hotspot to the degradation of organic pollutants in the field of environmental technology. Recently, highly active oxidation methods for the efficient degradation of PFOX were developed through the promotion effect of various physical processes on the oxidation ability of conventional chemical methods. So this paper reviews the concerned reports which employed the single chemical oxidation approach and the coupling techniques of physical processes and chemical oxidation for the removal of PFOX. The coupling effects of physical methods and chemical oxidation processes can result in photolysis, electrolysis, pyrolysis, sonolysis, plasma-induced oxidation, microwave-induced oxidation, or mechanochemistry destruction of PFOX. For each coupling physicochemical techniques, the mechanism of the oxidative reaction, the detailed degradation pathway of PFOX, the effect of various influential factors on reaction process as well as the removal efficiency and energy consumption are summarized in this paper. It is also introduced for the progress on these above studies and further discussion about current problems for these techniques. In addition, the future trends for the development of these techniques to PFOX degradation are prospected for their practicality.

Contents
1 Introduction
2 PFOX oxidation only by chemical reagents
3 Oxidative degradation of PFOX by various physicochemical processes
3.1 PFOX degradation by photochemistry
3.2 PFOX degradation by electrochemistry
3.3 PFOX degradation by thermochemistry
3.3.1 High-temperature pyrolysis
3.3.2 Ultrasonic pyrolysis
3.4 PFOX degradation by plasma
3.5 Microwave-assisted PFOX degradation
3.5 PFOX degradation by mechanochemistry
4 Conclusions and prospects