The chirality of nanoparticles determines their interaction with immune cells and the corre-spondent response in immune system. This finding provides a novel strategy for the design of vaccines to fight the infection of virus.

Membrane technology occupies an important position in chemical technology and is widely used in varied fields of industry and daily life. With the continuous development of thin film technology, the preparation of porous polymer films with controlled pore size and size distribution, excellent mechanical properties and functional versatility has become an urgent problem to be solved. Compared to non-porous dense polymer films, micro- and nanoporous polymer films generally have lower density, lighter weight, higher specific surface area, and feature acoustic and thermal insulation, good permeability and high plasticity. This review begins with a summary of the methods used to prepare micro/nano-porous polymer films, including template methods (hard and soft templates), phase separation, electrostatic spinning, etching and some other methods. The methods for characterizing the structure and related properties of membranes in porous polymer films are also introduced. The applications of porous permeable membranes are then summarized in gas separation, energy, environmental engineering and bioengineering. Finally, the drawbacks and challenges of current methods for the preparation of micro- and nanoporous polymer films are summarized and an outlook is given on their future innovative applications.

As a new two-dimensional layered material, transition metal carbides or nitrides (MXene) possess great potential in the fields of electrochemical sensing due to their good conductivity, water dispersion, high biocompatibility and stability. Incorporation of MXene with other nanomaterials could create complementary and synergistic effect for the composite, which will effectively improve the sensitivity and selectivity of electrochemical sensors. This paper summarizes the application of MXene based electrochemical sensing platforms for the detection of biomarkers and environmental pollutants in recent years, and the challenges of MXene materials in the fields of electrochemical sensing in the future are also discussed.

Solid oxide fuel cell (SOFC) is an energy conversion device with advantages of high conversion efficiency, eco-friendliness, fuel flexibility, etc. The anode is one of the key components of SOFC, where the fuel oxidation reaction takes place. Compared to the traditional anode Ni-YSZ, perovskite oxides show strong resistance to carbon deposition and sulfur poisoning. Due to the diversity of ion occupancy site in the lattice, double perovskite oxides exhibit a more tailorable feature in terms of lattice structure and electrochemical properties and therefore have attracted extensive attention as SOFC anode material. However, their poor catalytic activity and low electrical conductivity, compared with the traditional Ni-YSZ anode, limit the practical application. This work summaries the recent research work and advancement of double perovskite oxides as SOFC anode in the past decade. With a brief introduction of the structure characteristics and formation origins of A-site and B-site perovskite, the properties and modification strategies of the two kinds of double perovskite anode materials are reviewed, including Sr₂MgMoO₆, Sr₂CoMoO₆, Sr₂NiMoO₆, Sr₂FeMoO₆, PrBaMn₂O_5+δ, etc. In the end, we propose the main future research directions.

Lignin is a renewable resource with the advantages of low cost, high carbon content, high aromaticity and easy collection. Lignin is regarded as one of the most important raw carbonaceous materials for industry to prepare new porous carbon materials in a large scale. It is of great strategic significance to alleviate the consumption of fossil fuel resources and deepen the sustainable development. Porous carbon materials have an extraordinary application prospect in the fields of energy storage materials, because of their high conductivity, high specific surface area, abundant porosity, excellent stability, etc. In this review, the latest research advances and developments for the preparation of lignin-derived porous carbon materials (LPCM) by template, activation and hydrothermal methods are reviewed pivotally. Meanwhile, the influences of pyrolysis parameters on the micro-structure of LPCM are summarized in detail. Furthermore, the applications of LPCM as the electrode materials for lithium-ion batteries, sodium-ion batteries and supercapacitors are illustrated emphatically. However, there exist some bottlenecks that the preparation processes of LPCM are complicated and their energy storage performances are relatively poor. Thus, the optimization of ion/electron diffusion kinetics, the synergistic effect of multiple energy storage mechanisms and the development of the green and facile preparation processes are proposed to conquer these challenges. The development of advanced carbonization techniques to construct the reasonable hierarchical porous structure, precise regulating the suitable interlayer spacing and the highly ordered arrangement of carbon layers, functionally modifying surface microenvironment, and the direct establishment of the relationship between carbonization parameters and electrochemical performance are the research directions to prepare LPCM with the high energy storage performances in the future.

Nitrogen oxides (NO_x) can be reduced by technology of selective catalytic reduction (SCR) with NH₃, while the spent commercial V₂O₅/TiO₂ catalysts with biotoxicity for SCR technology is recognized as hazardous wastes in China. Rare earths (REEs) possess unique 4f electron orbit ensuring superior performance of oxygen storage and release, which plays a significant role in catalytic reaction. Thus, REEs are the important research subject in SCR catalysts recently and the proposed substitutes for V₂O₅/TiO₂ catalysts. This review mainly summarizes the progress of 12 REEs including Ce, Sm and La in novel SCR catalysts in recent 5 years, and there is seldom study on Sc, Lu, etc. We primarily review the effect of REEs on improving the catalytic activity, N₂ selectivity and stability of Mn-, Fe-, V- and other based DeNOx catalysts. The REEs mainly improve the redox behavior via the formation of redox couples with other transition elements and providing more oxygen vacancies. In the aspect of resistance towards SO₂, the REEs, such as Ce and Sm, could suppress the oxidation of SO₂ to SO₃ and attract the poison of SO₂ from the main active components, thus improving the resistance towards SO₂. We also review the molding and application of REEs-based catalysts. Additionally, the primitive design strategy of SCR catalysts is proposed, and the development prospect of REEs-based catalysts is forecast finally.

As a promising cathode of aluminum ion batteries (AIBs), transition metal chalcogenides (MX₂ (X=S, Se, Te)) have excellent theoretical specific capacity and lower electronegativity, which endow it with great potential in commercial AIBs. Here, the relationship between the aluminum storage mechanism and the electrochemical properties of the transition metal sulfide compound (MX₂ (X = S, Se, Te)) is summarized. According to the current problems of transition metal chalcogenides, we propose the corresponding solutions proposed by researchers and summarize the main material modification techniques. Finally, the development direction of transition metal chalcogenide cathode materials is prospected, and feasible strategies to improve its overall electrochemical performance are discussed.

It is well established that enantiomers often exhibit different biological and pharmacological responses. However, enantiomers remain a challenge to separate and analyze due to their identical physical and chemical properties in an achiral environment. Research on specialized separation techniques continues to be developed to obtain optically pure compounds. The separation of enantiomers by chromatographic methods, such as high-performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrochromatography (CEC), has become one of increasingly important research contents in chemistry over the past few decades due to the demand for pharmaceuticals, agrochemical, and food analysis. The chiral stationary phase (CSP) is key to separating and analyzing chiral compounds for these chromatographic resolution methods. With the rapid development of materials science, diverse types of porous materials as CSP have been studied in recent years. This review mainly focuses on investigating chiral porous materials as CSP for high-performance liquid chromatography (HPLC), gas chromatography (GC), and capillary electrochromatography (CEC) over the past five years. The chiral porous materials include chiral metal-organic frameworks (CMOFs), chiral covalent organic frameworks (CCOFs), chiral porous organic cages (CPOCs), chiral metal-organic cages (CMOCs), chiral microporous organic networks (MONs), and chiral mesoporous silicas (CMSs). Chiral recognition mechanisms of novel chiral porous materials are also discussed briefly. Finally, the related problems and prospects for CSP were briefly discussed.

It has become one of the main trends in the development of bone repair materials to design and control materials by imitating the composition and structural characteristics of natural bone to obtain new bionic artificial bone repair materials. Electrospun nanofibers are widely used in bone tissue engineering because of their adjustable nanostructure, high porosity, large specific surface area, and the ability to mimic the structure and biological functions of natural extracellular matrix. This review provides a comprehensive overview of electrospun nanofibers based on bone tissue engineering. We begin with a brief introduction of bone tissue engineering, followed by discussion of electrospinning principle, parameters and typical apparatus. We then discuss surface modification methods of electrospun nanofiber and highlight the most relevant and recent advances related to the applications of electrospun nanofibers and electrospun nanofiber reinforced composites by focusing on the most representative examples. Furthermore, we also offer perspectives of electrospun nanofibers on the challenges, opportunities, and new directions for future development.

Various forms of friction and wear not only consume more than 20% of the world’s total energy, but also cause an enormous amount of equipment damage. As a result, it is of great significance to develop friction-reducing and anti-wear lubricating materials for saving energy and prolonging the service life of mechanical equipment. Carbon dots (CDs), as a new kind of carbon nanomaterial, have been extensively used in chemical sensing, bioimaging, catalysis, optoelectronic devices and other fields. In recent years, a large number of studies have explored the application of CDs in the fields of industrial lubrication, micro/nano-electrical-mechanical systems lubrication and biological lubrication, proving that CDs have excellent tribological properties and great potential to become the next generation of green and efficient friction-reducing and anti-wear lubrication materials. However, it still lacks a systematic summary and discussion of the application of CDs in the field of lubrication. Consequently, in this paper, the research progress of CDs in lubrication applications is comprehensively and systematically summarized. Firstly, lubricating effects of CDs as nano-additives and lubricating coatings and three strategies (size and shape control, surface modification and heteroatom doping) to improve their lubrication performance are introduced in detail. Then, the lubrication mechanism of CDs is fully analyzed. Finally, the main challenges of the application of CDs in lubrication are outlined.

Lithium metal is considered as an ideal anode for next generation high energy density secondary batteries due to its high specific capacity (3860 mAh·g^-1) and low redox potential (-3.04 V vs standard hydrogen electrode). However, the "hostless" lithium metal is plated/stripped at the metal/electrolyte interface layer, inevitably growing dendrites and resulting in uneven distribution of current on the surface of lithium metal, which may puncture the battery separator and cause short circuit of the battery. In practical applications, by constructing three-dimensional current collector/lithium metal composite anode, the lithium deposition behavior can be effectively regulated and the dendrite can be suppressed, which further enhances the Coulombic efficiency, cycling life and rate performance. The research on this aspect has become a hot topic in recent years. In this review, firstly, the related principles and models of the suppression of lithium dendrite based on 3D current collector are summarized. Secondly, for the copper-based current collector, the preparation methods of 3D current collectors and their application in the protection of lithium metal anode are systematically summarized according to the dimension of substrate units. Finally, we summarize and outlook on the composite lithium anode constructed by 3D current collectors.

Replica exchange molecular dynamics (REMD) is a kind of enhanced sampling algorithm that has been widely used in the study of protein conformation changes with their free energy landscape. Due to its rigorous principle and high sampling efficiency, researches on the optimization and development of the conventional REMD method have also sprung up, and have been in the ascendant recently, which greatly enhances its sampling efficiency and expands its application. However, those REMD variations usually have specific application, making it difficult to choose suitable REMD variations in practical application. Therefore, it is of great significance to summarize the REMD variations for understanding their advantages and disadvantages and for choosing suitable REMD variations. Here, we review recent development of the REMD variations from the perspective of their principle, and classify them into six types of methods: I) improving the approach and swapping rate of replica exchange, II) reducing the potential energy on exchange attempts to reduce the number of replica, III) Hamiltonians replica exchange molecular dynamics, IV) adjusting simulation process to improve sampling efficiency, V) changing the sampling methods, VI) adapting to heterogeneous and distributed computing environment. We hope that this review may be helpful in the understanding, application, and further improvement of the various REMD variations.

The low extracellular electron transfer (EET) efficiency dominated by electro-active bacteria (EAB) in traditional bio-electrocatalytic systems (BESs) has largely restrained the applications of microbial electrocatalysis in environmental and industrial fields. To break this bottleneck, many scientists from the world attempted to develop advanced catalysts to improve the efficiency of electron transfer in BESs. It is expected that rational optimization by multi-disciplines technologies, including material science, electronic microbiology and synthetic biology, will improve the electron flux and efficiency of electron transfer. This optimization might promote the transition from traditional inorganic catalysts towards living catalytic biomaterials which promises to upgrade to be more precise, intelligent and controllable advanced materials in the future. The promotion will provide more beneficial technical support for the large scale application of advanced materials. Herein, this paper summarizes the effective constructions of several kinds of BESs (including employing graphene/microbes composited materials, in-situ semiconducting photocatalytic self-assembled biohybrids, core/shell-coated biohybrids and genetically manipulated engineering strains). In addition, the mechanisms regarding the strategies for strengthening EET are also elaborated in this paper. At last, current challenges that exist for microbes-based living biomaterials and underlying opportunities of biomaterials used in more environmental applications in the future are summarized.

The emitting materials with thermally activated delayed fluorescence (TADF) characteristics have received increasing attention in recent years. As a typical d¹⁰ metal, Cu(Ⅰ) is the most widely investigated one used to construct d¹⁰ metal-organic complexes. The copper metal-organic complexes often have certain superior luminescence properties because they can harvest both singlet and triplet excitons and exhibit much higher luminescence quantum yields close to 100%. They are cost-effectiveness and comparable with phosphorescent materials in terms of device efficiency. In addition, they have lowlying metal to ligand charge transfer(MLCT) excited states with small energy difference between the lowest singlet state and the lowest triplet state (ΔE_ST), which is a key point to facilitate the reverse intersystem crossing (RISC) process in tuning triplet excitons to singlet excitons for TADF emission. Meanwhile, the energy difference can be adjusted by different ligands or substituents. In this paper, we summarize and analyze the structure and luminescent properties of TADF copper complexes reported in recent five years, according to the types of the coordination atoms. These complexes are classified into four classes,and the coordination atoms are mainly N, P, X (halogen), C, S(O). We mainly discuss the effects of the structures on the luminescent properties. Finally, the potential applications in organic light-emitting diodes(OLEDs) are also prospected.

Recently, the capacities and energy densities of graphite anode material and lithium transition metal oxide cathode materials for commercial lithium ion batteries are approaching their theoretical values. Exploring the next generation of high-energy density electrode materials is the key factor to solve the capacity limitation of lithium ion batteries at the present stage. New metal oxalate-based anode materials have been considered as a kind of green energy storage material with broad application prospects in metal ion batteries by virtue of the high energy density and excellent cycling stability with the aid of their diversified energy storage mechanism. In this paper, we review the latest research on metal oxalate-based anode materials in lithium, sodium and potassium metal ion batteries, and emphatically introduce their crystal structures, diversified energy storage mechanism and dynamics characteristics in the process of energy storage. The problems existing in electrochemical energy storage of materials are briefly described and their modification strategies based on controlling of crystal structure and morphology, interface carbon composite and metal elements doping are analyzed. Furthermore, the development direction of metal oxalate-base anode materials in alkali metal (Li, Na, K) ion battery system is predicted.

In the recent years, designing and synthesizing high-performance nonfullerene acceptor (NFA) materials have become the mainstream on research of organic solar cells (OSCs). Fused-ring based NFAs show high absorption coefficients, adjustable energy levels and bandgaps, straightforward synthesis, and excellent electrical and photovoltaic properties. The power conversion efficiencies (PCEs) have been increased from 3%~4% to 18% just in 7 years. In 2019, Zou et al. reported a smart acceptor molecule, named Y6, which supplied a very impressive PCE of 15.7% when pairing with PM6. Y6 and its analogs were featured with DA'D type fused-ring as the central electron-donating (D) units. The electron-accepting (A') unit was fused through nitrogen with two D units, which helped to downshift the Frontier molecular orbitals and enhance light absorption. Again, the steric effect between the two N-linked alkyl chains and the decorated chains on the fused thienothiophene-β-positions helped to increase the solubility and tune crystallinity. After the report of the smart Y6, intense investigations have been made on structure cutting of the molecule and tens of new structures have been reported. Among these new acceptors, structural tailoring on the DA'D moiety plays a vital role in improving device efficiency and solar cell performance. In this review, we focus on the recent advances on the structural modifications on A' and D units and side chains. We set up several sets of acceptors, by which we classify the recently reported molecules and correlate their optical, electrochemical, electrical and photovoltaic properties with the precise structural modulations so as to present a comprehensive review on the structure-property relationship.

Bimetallic organic frameworks and their derivatives have the characteristics of rich pore structure, large specific surface area, adjustable structure, abundant active sites, as well as the synergistic effect between bi-component and porous structure, so they are paid close attention to by researchers and widely used in electrochemical energy storage, catalysis, separation, sensors, medicine, gas storage and other fields. Just as monometallic organic frameworks, the poor conductivity and collapsible structure of bimetallic organic frameworks greatly limit their applications in electrochemical energy storage. It is through heat treatment of bimetallic organic frameworks that porous carbon@bimetallic oxide/sulfide/phosphide/selenide derivatives with uniform distribution, which not only keep rich pore structure, but also have improved conductivity and structural stability, being conducive to the application in the field of electrochemical energy storage are obtained. Therefore, in the view of the main metal ions in the bimetallic organic frameworks, this research reviewes the latest progress of the organic frameworks and their derivatives in electrochemical energy storage devices such as supercapacitors, lithium ion batteries, sodium ion batteries, and metal-air batteries, respectively. On this basis, the advantages of bimetallic MOFs in the application of electrochemical energy storage are summarized, and suggestions on its preparation, mechanism and post-treatment are put forward.

The Diels-Alder reaction (D-A) is considered as one of the cornerstone reactions in modern organic chemistry due to its powerful ability to build the structured organic compounds. Since it was discovered in 1928, the D-A reaction has been further developed, mainly because it can produce six-membered rings along with the generation of up to four stereogenic centers in one step, which greatly increases the molecule complexity. This particular transformation has been widely used in the synthesis of complex natural products as well as pharmaceutical chemistry or materials science and other fields. In the last decade, many natural biological enzymes (such as SpnF, MaDA, etc.) have been found to be used to catalyze D-A reactions in vitro. On the other hand, many other non-enzymatic catalysts (such as Lewis acid, transition metal and ligand complexes, etc.) have also been applied in the catalytic process of D-A reaction. This article mainly classifies the reaction catalysts, and briefly summarizes D-A reactions involving natural enzymes, acids, transition metals, and electrocatalysis in recent years. At the same time, the deficiencies as well as perspective of the catalyst have been highlighted.