The alkaline earth metal cations-bridged polyoxometalate anions nanoclusters subnanometer nanowires were prepared through a facile room-temperature reaction. These nanowires could form 3D networks in the dispersion, and thus locked volatile organic liquids and formed gels. This finding provides a new strategy for safe storage and transportation of organic liquids and recovery of spilled oil.

Tau protein is a microtubule-associated protein that contains six isoforms and consists 352~441 amino acids. Misfolding and aggregation of Tau protein are closely related to Tauopathies, including Alzheimer’s disease (AD). In the brain of AD patients, it is indicated that post-translational modification plays a key factor in the pathogenesis of AD. This paper reviews the post-translational modifications of Tau protein and the progress in chemical synthetic/semisynthetic preparation of uniform Tau protein with specific site modification. Reviewing the research of post-translational modification of Tau protein, clarifies the regulatory mechanism of post-translational modification, which will help us to understand the physiological and pathological effects of post-translational modification on Tau protein and further develop potential disease treatment methods.

At the 75th session of the United Nations General Assembly, China made a solemn commitment to strive to achieve carbon peaking by 2030 and carbon neutrality by 2060. Biomass, mainly produced by photosynthesis, will play an important role in the dual carbon targets. The efficient conversion of biomass can yield a range of high-value chemicals to replace fossil-derived products. Among these biomasses, 2,5-furandicarboxylic acid (FDCA) can be used to replace petroleum-based terephthalic acid (TPA) in the synthesis of bio-based furan polyesters with better thermal stability and gas barrier properties due to its similar conjugated carbon ring and diacid structure to TPA, significantly reducing the heavy reliance on fossil resources in polyester industry. In addition, FDCA is widely applied to pharmaceuticals, fragrances and metal coordination chemistry, making it one of the twelve most promising bio-based platform compounds. FDCA is typically synthesized by catalytic oxidation of 5-hydroxymethyl furfural (HMF). Compared to conventional thermocatalytic methods that require precious metal catalysts, high temperature and pressure conditions, and chemical potential as the driving force, electrocatalytic oxidation uses electrode potential as the main driving force and is a novel synthesis method that is greener and more efficient. This review summarises and analyzes the noble metal, transition metal and non-metal catalysts used in the preparation of FDCA reactions by electrocatalytic oxidation, outlines the research on catalyst design and reaction mechanisms, and points out the challenges and opportunities for the development of this field.

The control of NO_x is very important for the air quality improvement. Selective catalytic reduction of NO_x by hydrogen (H₂-SCR) has attracted much attention as an efficient and environmentally benign deNO_x technology. In this review, we summarize the research development in the H₂-SCR of NO_x over noble metal catalysts. The typical H₂-SCR reaction mechanisms are introduced first. Then the factors affecting the H₂-SCR performance of noble metal catalysts, such as the active metal, support type, the added promoter and the nature of active metal, and the structure-activity relationship have been discussed. Finally, the challenges and the prospects for future development of H₂-SCR catalyst are proposed.

Cu-exchanged zeolite SSZ-13 (Cu-SSZ-13) has been proven to be an excellent catalyst for the NH₃-SCR of NO_x from diesel engine exhaust. This review summarizes the effect of Brønsted acid sites and framework Al atoms on the location and migration of Cu species in CHA cage, emphasizing the importance of paired Brønsted acid sites and ‘strong Al pairs’ in the hydrothermal stability of Cu-SSZ-13. The latest advances in methods to control the formation of framework ‘Al pairs’ is described as well. Based on the analysis of the catalytic performances of Cu-SSZ-13 synthesized with different organic templates, the possibility of synthesizing Cu-SSZ-13 with great catalytic performance and low cost is pointed out.

Over the past decades, metal-halide perovskite solar cells (PSCs) have seen rapid development and gained extensive attention because of their excellent advantages of high light absorption coefficient, longer carrier diffusion distance, lower preparation cost, etc. By now, the champion power conversion efficiency (PCE) has reached 25.5% within a few decades. However, the PCE of the device is still lower than the Shockley-Queisser (S-Q) theoretical limit due to the fact that various non-radiative recombination losses usually take place during carrier transport process. In this review, we first introduce the device structure and working principle of PSCs, and then summarize common non-radiative recombination loss pathways, including defect-assisted Shockley-Read-Hall (SRH) recombination, interface-induced recombination, Auger recombination, band-tail recombination processes, etc. These recombination modes are the main reasons leading to low efficiency and poor stability of PSCs, and thus have drawn considerable attention among researchers. Based on the latest research works, we summarize the general regulation strategies to reduce the undesired non-radiative recombination processes for the construction of high-efficiency and stable PSCs. These efficient regulation strategies mainly include reduction of perovskite crystal defects, passivation of grain boundary defects, passivation of interface defects and optimization of energy level structure. Finally, the opportunities and challenges for the development prospects of non-radiative recombination regulation are discussed.

Linear-dendritic block copolymers (LDBCs) are composed of a linear polymer and dendrimers (dendrons). They not only combine the characteristics of the two types of polymers, but also have unique structures and properties. Furthermore, stimuli-responsive LDBCs can be generated through the selection and structural modification of their linear chains and dendrons. Stimuli-responsive LDBCs have attracted much attention in recent years because of combining the ability to respond to a specific stimulus and different polymeric architectures for a broad range of applications, including drug delivery, gene therapy and materials science. Among them, enzyme responsive LDBCs are able to specifically respond to endogenous enzymes. Compared with the polymers that are able to only respond to exogenous stimuli such as temperature, light, etc, enzyme responsive LDBCs have high selectivity and better biocompatibility. Therefore, they are more suitable for application in in vivo as biomedical materials. Amphiphilic enzyme responsive LDBCs are capable of self-assembling in aqueous solution into nano-aggregates and disassembling to release payloads upon enzymatic stimuli. Additionally, the self-assembly and enzyme responsive disassembly properties of amphiphilic enzyme responsive LDBCs can be adjusted by changing the enzyme-responsive groups, linear chains and dendrons of LDBCs. Due to their unique enzyme response properties and excellent biocompatibility, enzyme responsive LDBCs have broad application prospects in drug delivery, biomedical imaging, etc. Herein, this review summarizes the synthetic approaches of enzyme responsive LDBCs, the effect of the structures such as the length and structure of linear chain, and hydrophobicity of dendrons of the LDBCs on their self-assembly properties and enzyme-responsive properties. The applications of these copolymers are also introduced. Finally, the research prospect of enzyme responsive LDBCs are proposed.

Blue phase (BP) liquid crystals have been regarded as one kind of the most promising candidates for tunable three-dimensional photonic crystals due to their unique 3D self-assembly nanostructures, photonic bandgaps in visible light range and characteristics of soft matter. They exhibit great potential in numerous applications such as next-generation ultra-fast displays, reflection-mode displays, tunable lasers and optical communication devices. Herein, we provide the research advancement in the self-assembly structures of blue phase liquid crystals in recent years. First, the latest research on the hierarchical self-assembly of three-dimensional micro/nano structural and phase transition behaviors between three sub-phases are introduced. Then, the control methods of their self-assembly behavior or three-dimensional periodic lattice structures are demonstrated in detail. The lattice nucleation growth and lattice orientation of BPI and BPII can be modulated by substrate surface orientation treatment or nano patterning treatment. Owing to the response characteristics of BPs to external electric field, monodomain cubic crystals of BP or new sub-phase with non-cubic nanostructure can be obtained by controlling applied electric field. Besides, BP photonic crystals with different plane orientations can be obtained in a short time by appropriate heat treatment. These studies provide theoretical foundation for the appreciable application of BP materials in three-dimensional photonic crystals and functional devices. For example, the applications of blue phase liquid crystalline photonic crystal materials in optical fields such as tunable laser and tunable grating are shown. At the end of this review, the challenges and possible development direction of blue phase liquid crystalline photonic crystal is prospected briefly.

Furfuryl alcohol (FOL), as an important and promising organic chemical product, can be effectively converted into various high-value chemicals, such as furfural resin, urea-formaldehyde resin, phenolic resin, fruit acid, plasticizer, rocket fuel, etc. The green FOL production by catalytic hydrogenation using furfural (FAL), xylose, and fructose as raw materials has good application prospects and research values. This article systematically reviews the research status of the FOL production from FAL, xylose, and fructose on the recent advances, and summarizes from the aspects of catalyst types, catalytic efficiency and mechanism for FOL production. On this basis, the development trends of the FOL production by catalytic hydrogenation are prospected, which may provide theoretical guidance and useful reference for developing new efficient green and stable catalytic system.

A liquid plasticine (LP) refers to a self-standing liquid system coated by hydrophobic particles in air environment, which is featured by plasticity and complex shape. As emerging soft matter systems, LPs have been successfully applied in several areas including gas sensing, protein analysis, and photocatalysis, with important and peculiar advantages. In this review, we first analyze the initial development stage of LP study with discussions on liquid shape and surface jamming. Non-wetting droplets including naked droplets supported by superhydrophobic surfaces and particle-covered spherical liquid marbles (LMs) are involved in the discussion and their relationships with LPs are clarified. We then summarize the current progress of LPs, with discussions on the preparations, properties, and applications. Nearly all kinds of LPs are discussed, and particular attention is paid to monolayer nanoparticle covered (mNPc) LPs considering the study on which is currently the most comprehensive and systematic. In the end, we summarize and analyze the concept connotation of liquid plasticine, the key issues in the preparation, the main differences between different LPs, and the application potentials. We also point out several research directions for future study with suggestions on the idea conception.

Molecular strain plays a key role in steric design of organic semiconductors. Molecular strain includes the stretch strain, torsion/ bend stain, and steric strain that make special p-orbital arrangements and conformation/configuration change. Recently, diverse highly strained molecules have been reported with various topological and geometric structures, in which organic semiconductors with high strain energy become more and more important in the field of organic optoelectronic materials and their flexible electronics. In order to further get insight into the role of molecular strain in the organic semiconductor materials, the types of molecular strain, theoretical/ experimental quantification and visualization are introduced firstly in the review. Then, the strategies of molecular design are summarized for the highly strained π-conjugated arenes. Next, the effect of molecular strain on optoelectronic properties of semiconductor materials and their application are highlighted in the field of organic electronics. Finally, the problems faced by highly strained organic semiconductors are discussed and addressed to shed light on the research prospects of these materials.

Metal oxide semiconductors-based chemiresistive gas sensors have been extensively researched and applied to detect gas molecules due to their advantages of high sensitivity, long service life, and low cost. However, the interactions between the sensing layer and water molecules cause variations of the baseline resistance and surface state, and thus the gas sensing performance is significantly affected by ambient water molecules, resulting in a bottleneck in applications. To solve this problem, researchers have developed many strategies to improve the anti-humidity performance of metal oxides based on these concepts of inhibiting the surface adsorption of water, suppressing the competitive adsorption between water molecules and oxygen species, or regulating the chemical reactions between water molecules and adsorbed oxygen. The specific approaches of the mentioned strategies are summarized as follows. (1) Introducing the hydrophobic and breathable coating on the surface of the gas sensing layer, which can physically prevent water molecules from touching the surface of sensing layers and directly eliminate the damage. (2) By doping the gas-sensitive material with hydroxyl absorbents, the water molecules will preferentially adsorb on the surface of hydroxyl absorbents, thereby inhibiting the competition adsorption between vapor and oxygen at active reaction sites. (3) Adjust the chemical adsorption characteristics of oxygen anions on the surface, change the chemical and electronic effects of the surface, or reduce the adsorbed oxygen that has formed hydroxyl groups with water, inhibit the reaction process of water and oxygen, and maintain the concentration of adsorbed oxygen, thereby improving the anti-humidity performance of the semiconductor gas sensors. Here, the influence mechanism of the water molecule on gas sensing performance is analyzed and the future development of the mentioned anti-humidity promotion strategies has been prospected. This article is expected to provide solutions and method guidance for the improvement in the anti-humidity performance of gas-sensitive materials based on metal oxide semiconductors.

Atom transfer radical polymerization (ATRP) is an important method for preparing polymers with controllable molecular weight and polydispersity. However, due to the complex oxygen removal steps, metal catalysts residue, and limited monomer scope, it is difficult for ATRP to be widely used in the large-scale preparation of functionalized polymers/copolymers. With the development of enzyme-catalyzed polymerization, radical polymerization has made significant progress in efficient and convenient oxygen removal, expanding monomer scope, and the synthesis of polymers/copolymers with special (nano) structures. This review highlights the structure of enzymes and their catalytic mechanism in enzyme-catalyzed ATRP. Various enzyme/ enzyme mimics catalysis system (including horseradish peroxidase, hemoglobin, heme, laccase, etc.) employed in ATRP are carefully summarized in order. Finally, the opportunities and challenges of enzyme-catalyzed ATRP are discussed for the further development in this field.

TiO₂ based photocatalytic technology is of wide application in the fields of pollutant degradation, CO₂ reduction, hydrogen production, etc. owing to its set of intriguing properties, including fast reaction speed, high visible light utilization efficiency, and no secondary pollution. However, the low utilization rate of visible light for TiO₂ materials limits it further use. In recent years, lead-free halide perovskite nanocrystals are of great interest in the field of photocatalysis due to their notable advantages such as tunable band gap and high visible light absorption. Relevant studies show that lead-free halide perovskite nanocrystals can be successfully applied in the fields of CO₂ reduction and organic pollutant degradation, with significant effects. This review describes the preparation methods of lead-free halide perovskite nanocrystals, and summarizes its applications in the fields of CO₂ reduction, hydrogen production, pollutant degradation and NO removal systematically. Finally, the current issues of lead-free halide perovskite nanocrystals as photocatalytic materials and the outlook for the future directions are discussed and prospected.

O-phenylenediamine (OPD) can be easily oxidized by a variety of oxidants to form yellow fluorescent substance 2, 3-diaminophenazine (OPDox), and the unique responding mechanism provides a principle in the design of reaction-based colorimetric/fluorescent probes. Up to now, colorimetric and fluorescent probes based on the OPD oxidative reactions have been widely applied in the detection of metal ions and organic molecules. In recent years, these probes have attracted much attention in the recognition of bio-molecules in cells and tissues due to their high sensitivity, fast response speed and strong anti-interference ability. This review summarizes the development of colorimetric and fluorescent probes based on the OPD oxidative reactions in the detection of important bio-molecules such as biothiols, reactive oxygen species, uric acid, enzyme, antigen and so on. We further make an in-depth perspectives on the application and development prospect of the probes.

Cysteine (Cys) is one of the three biological thiols. It is the only natural amino acid containing a reducing sulfhydryl group among the twenty natural amino acids. It is one of the basic amino acids that composes intracellular polypeptides and proteins. It participates in redox regulation of cells, regulates the redox balance in the body, and maintains the normal metabolism of the body, which plays a vital role in the physiological process. However, abnormal levels of Cys concentration in the body can cause a series of physiological diseases, and the concentration of Cys in the body has clinical significance as a biomarker of several diseases. Therefore, the effective identification and detection of cysteine is favored by more and more researchers. Compared with traditional detection methods, fluorescent probes have been widely used to detect biological thiols because of their simple operation, high sensitivity, rapid response and real-time detection. Based on the structural and performance characteristics of common fluorophores, this article reviews the fluorescent probes used to detect Cys in the past three years, focuses on their sensing mechanisms, briefly describes its biological applications, and prospects the future research directions and application prospects of Cys probes.

Metal-organic frameworks (MOFs) are a kind of porous coordination polymers formed by the assembly of metal ions and organic ligands, exhibit excellent advantages as a nanocarrier, such as easy modification, high drug loading as well as controllable drug release. The diversities of metal ions and organic ligands lead to the diversities of MOFs, which make them wide application in many fields such as storage and separation, catalysis, sensing, biomedical application and others. With high porosity, versatile MOFs allow for the facile encapsulation of various therapeutic agents with exceptionally high payloads. Especially when the particle size of MOFs is controlled down to the nanometer level, named nanoscale metal-organic frameworks (NMOFs), they exhibit a series of structural advantages. Based on the above advantages, NMOFs exhibit excellent application prospects for drug delivery and cancer therapy. NMOFs can be used as therapeutic agents, as well as nanocarriers of drug, photothermal agents, photosensitizers and Fenton reaction catalysis to using passive targeting, active targeting, physicochemical targeting, or combination of the three. The review focuses on the application of chemotherapy (CT), photothermal therapy (PTT), photodynamic therapy (PDT), chemodynamic therapy (CDT) and various combination therapies. Finally, we will elaborate the current challenges and future development prospects of NMOFs in cancer application.