Designing high-performance nonfused ring electron acceptors via side-chain engineering

The side-chain has a significant influence on the optical properties and aggregation behaviors of the organic small molecule acceptors,which becomes an important strategy to optimize the photovoltaic performance of organic solar cells.In this work,we designed and synthesized three brand-new nonfused ring electron acceptors(NFREAs)OC4-4Cl-Ph,OC4-4Cl-Th,and OC4-4Cl-C8 with hexylbenzene,hexylthiophene,and octyl side chains on theπ-bridge units.Compared with OC4-4Cl-Ph and OC4-4Cl-Th,OC4-4Cl-C8 with linear alkyl side chain has more red-shift absorption,which is conducive to obtaining higher short-circuit current density.Additionally,the OC4-4Cl-C8 film exhibits a longer exciton diffusion distance,and the D18:OC4-4Cl-C8 blend film displays faster hole transfer,weaker bimolecular recombination,and more efficient exciton transport.Furthermore,The D18:OC4-4Cl-C8 blend films may effectively form interpenetrating networks that resemble nanofibrils,which can facilitate exciton dissociation and charge transport.Finally,OC4-4Cl-C8-based devices can be created a marvellously power conversion efficiency(PCE)of 16.56%,which is much higher than OC4-4Cl-Ph(12.29%)-and OC4-4Cl-Th-based(11.00%)ones,being the highest PCE among the NFREA based binary devices.All in all,we have validated that side-chain engineering is an efficient way to achieve high-performance NFREAs.

High-efficiency thermally activated delayed fluorescence materials via a shamrock-shaped design strategy to enable OLEDs with external quantum efficiency over 38%

To achieve highly-efficient organic light-emitting diodes(OLEDs),great efforts have been devoted into constructing thermally activated delayed fluorescence(TADF)with high horizontal dipole ratios(Θ//).Here,we proposed a design strategy by integrating a rigid electron-accepting oxygen-bridged boron core with triple electron-donating groups,which exhibited a“shamrock-shape”,namely BO-3DMAC and BO-3DPAC.Benefiting from the rigid and large-planar skeletons brought by shamrock-shaped design,BO-3DMAC and BO-3DPAC exhibit highΘ//of 84%/70%and 93%/94%in neat/doped films,respectively,and finally furnish excellent external quantum efficiencies(EQEs)of up to 28.3%and 38.7%in 20 wt%doped OLEDs with sky-blue emission,as well as adequate EQEs of up to 21.0%and 16.7%in nondoped OLEDs.This work unveils a promising strategy to establish high-Θ//TADF emitters by constructing large-planar molecular structures using shamrock-shaped design.

Therapeutic dendritic cell vaccines engineered with antigen-biomineralized Bi_(2)S_(3) nanoparticles for personalized tumor radioimmunotherapy

Therapeutic vaccines,an exciting development in cancer immunotherapy,share the goal of priming of personalized antigen-specific T-cell response by precise antigen presentation of dendritic cells(DCs),but major obstacles include insufficient antigen loading and off-target to DCs remain to their success.Here,we developed an imageable therapeutic vaccine with whole-antigen loading and target delivery constructed by ovalbumin(OVA)-biomineralized Bi_(2)S_(3) nanoparticles-pulsed DCs.Relying on the strong X-ray absorption and fluorescence labeling performance of Bi_(2)S_(3)@OVA nanoparticles,the in vivo spatiotemporal fate of the vaccine(Bi_(2)S_(3)@OVA@DC)can be noninvasively monitored by computed tomography and near-infrared fluorescence imaging in real time.The Bi_(2)S_(3)@OVA@DC can rapidly and durably accumulate in draining lymph nodes and thus trigger stronger T-cell responses compared to OVA-pulsed DCs.Meanwhile,Bi_(2)S_(3)@OVA@DC can further achieve in vivo antitumor effects against OVA-expressing B16F10 melanoma when combined with fractionated radiotherapy,resulting from the upregulation of cytotoxic CD8^(+)T cells and restraint of regulatory T cells in the tumor microenvironment,and the systemical secretion of OVA-specific IgG1/IgG2α antibody.Overall,we successfully fabricated an engineered DC vaccine featured in high whole-antigen loading capacity that can be precisely delivered to the lymphatic system for visualization,serving as a powerful therapeutic platform for cancer radioimmunotherapy.

Fire-retardant and high-strength polymeric materials enabled by supramolecular aggregates Special Collection:Distinguished Australian Researchers

High-performance polymers have proliferated in modern society across a variety of industries because of their low density,good chemical stability,and superior mechanical properties.However,while polymers are widely applied,frequent fire disasters induced by their intrinsic flammability have caused massive impacts on human beings,the economy,and the environment.Supramolecular chemistry has recently been intensively researched to provide fire retardancy for polymers via the physical barrier and char-catalyzing effects of supramolecular aggregates.In parallel,the noncovalent interactions between supramolecular and polymer chains,such as hydrogen bonding,π-πinteractions,metal-ligand coordination,and synergistic interactions,can endow the matrix with enhanced mechanical strength.This makes it possible to integrate physical-chemical properties and noncovalent interactions into one supramolecular aggregate-based high-performance polymeric system on demand.However,fulfilling these promises needs more research.Here,we provide an overview of the latest research advances of fire-retardant and high-strength polymer materials based on supramolecular structures and interactions of aggregates.This work reviews their conceptual design,characterization,modification principles,performances,applications,and mechanisms.Finally,development challenges and perspectives on future research are also discussed.

Sustainable biomedical microfibers from natural products

Microfibers from natural products are endowed with remarkable biocompatibility,biodegradability,sustainable utilization as well as environmental protection char-acteristics etc.Benefitting from these advantages,microfibers have demonstrated their prominent values in biomedical applications.This review comprehensively summarizes the relevant research progress of sustainable microfibers from natural products and their biomedical applications.To begin,common natural elements are introduced for the microfiber fabrication.After that,the focus is on the specific fabri-cation technology and process.Subsequently,biomedical applications of sustainable microfibers are discussed in detail.Last but not least,the main challenges during the development process are summarized,followed by a vision for future development opportunities.

Dynamical evolution of Ge quantum dots on Si(111):From island formation to high temperature decay

Heteroepitaxial growth is a process of profound fundamental importance as well as an avenue to realize nanostructures such as Ge/Si quantum dots(QDs),with appealing properties for applications in opto-and nanoelectronics.However,controlling the Ge/Si QD size,shape,and composition remains a major obstacle to their practical implementation.Here,Ge nanostructures on Si(111)were investigated in situ and in real-time by low energy electron microscopy(LEEM),enabling the observation of the transition from wetting layer formation to 3D island growth and decay.The island size,shape,and distribution depend strongly on the growth temperature.As the deposition temperature increases,the islands become larger and sparser,consistent with Brownian nucleation and capture dynamics.At 550◦C,two distinct Ge/Si nanostructures are formed with bright and dark appearances that correspond to flat,atoll-like and tall,faceted islands,respectively.During annealing,the faceted islands increase in size at the expense of the flat ones,indicating that the faceted islands are thermodynamically more stable.In contrast,triangular islands with uniform morphology are obtained from deposition at 600◦C,suggesting that the growth more closely follows the ideal shape.During annealing,the islands formed at 600◦C initially show no change in morphology and size and then rupture simultaneously,signaling a homogeneous chemical potential of the islands.These observations reveal the role of dynamics and energetics in the evolution of Ge/Si QDs,which can serve as a step towards the precise control over the Ge nanostructure size,shape,composition,and distribution on Si(111).

Aggregation in carbon dots

Carbon dots(CDs)possess outstanding luminescence properties,making them widely used in optical displays,anti-counterfeiting systems,bioimaging,and sensors.Presently,there is much debate about the classification of CDs,as well as their formation process,structure,and fluorescence mechanisms.Aggregation plays an important role in the formation and fluorescence(e.g.,aggregationinduced emission)of CDs,yet is seldom studied in detail.This review aims fill this knowledge gap,by first exploring how aggregation leads to the formation of different types of CDs(e.g.,graphene quantum dots,carbon quantum dots,and carbonized polymer dots),followed by a detailed examination of the effect of aggregation-induced morphology on the luminescence properties and application of CDs.Finally,opportunities and challenges for the application of CDs in various applications are discussed,with the need for better mechanistic understanding of aggregation-induced luminescence being an imperative.

A tumor-targeting nano-adjuvant for in situ vaccine based on ultrasound therapy

Ultrasound-generated antigens combined with TLR7/8 agonists as adjuvants have demonstrated significant anti-tumor efficacy as an in-situ vaccine.However,the use of TLR7/8 agonists can cause severe inflammatory responses.In this study,we present a novel tumor-targeting nano-adjuvant termed aPDL1-PLG/R848 NPs,which are composed of aPDL1 antibody,Fc-III-4C peptide linker(Fc-linker)and poly(L-glutamic acid)-grafted-R848.Under ultrasound irradiation,antigen-presenting cells activate immune mechanisms in vivo under dual stimulation of in situ antigens and immune adjuvants.The strategy inhibits primary tumor growth and induces a strong antigen-specific immune memory effect to prevent tumor recurrence in vivo.This work offers a safe and potent platform for an in situ cancer vaccine based on ultrasound therapy.

Oxygen-driven cuproptosis synergizes with radiotherapy to potentiate tumor immunotherapy

The immunological implications of cuproptosis,a form of cell death highly sensitive to oxygen presence,remain largely unexplored in the context of tumor immunother-apy.Herein,we initially investigate the positive correlation between cuproptosis and tumor immunotherapy through bioinformatics analysis.Subsequently,an oxygen generator loaded with copper ions(Cu/APH-M)has been constructed,which serves as an effective carrier of copper ions and crucially enhances the oxygenation of the tumor microenvironment.Importantly,Cu/APH-M-mediated dual strengthening of cuproptosis and radiotherapy could not only trigger a powerful antitumor immunity related to immunogenic cell death by RNA-sequencing analysis,but also effec-tively inhibit the growth of both distal and in situ low rectal tumors after combined immunotherapy,creating a robust immune memory effect.Our work reveals the ben-eficial effects of enhanced cuproptosis in radio-immunotherapy and elucidates its underlying mechanisms,which provides a novel approach for the synergistic inte-gration of cuproptosis with immunotherapy and radiotherapy,broadening the scope of cuproptosis-mediated tumor therapy.

Flexible antibacterial degradable bioelastomer nanocomposites for ultrasensitive human–machine interaction sensing enabled by machine learning

Flexible wearables have attracted extensive interests for personal human motion sensing,intelligent disease diagnosis,and multifunctional electronic skins.How-ever,the reported flexible sensors,mostly exhibited narrow detection range,low sensitivity,limited degradability to aggravate environmental pollution from vast electronic wastes,and poor antibacterial performance to hardly improve skin dis-comfort and skin inflammation from bacterial growth under long-term wearing.Herein,bioinspired from human skin featuring highly sensitive tactile sensation with spinous microstructures for amplifying sensing sensitivity between epidermis and dermis,a wearable antibacterial degradable electronics is prepared from degrad-able elastomeric substrate with MXene-coated spinous microstructures templated from lotus leaf assembled with the interdigitated electrode.The degradable elas-tomer is facilely obtained with tunable modulus to match the modulus of human skin with improved hydrophilicity for rapid degradation.The as-obtained sensor displays ultra-low detection limit(0.2 Pa),higher sensitivity(up to 540.2 kPa^(-1)),outstand-ing cycling stability(>23,000 cycles),a wide detection range,robust degradability,and excellent antibacterial capability.Facilitated by machine learning,the collected sensing signals from the integrated sensors on volunteer's fingers to the related American Sign Language are effectively recognized with an accuracy up to 99%,showing excellent potential in wireless human movement sensing and smart machine learning-enabled human-machine interaction.

The correlation between thermally induced precipitateto-coacervate transition and glass transition in a polyelectrolyte-bolaamphiphile complex

The precipitate and the coacervate are two aggregated states in the polyelectrolyte complexes(PECs).The precipitate-to-coacervate transition and glass transition in PECs have been widely reported in the past.In many cases,the two phenomena are studied independently,although both of them are apparently affected by water and small ions.Here,utilizing a PEC system consisting of poly(acrylic acid)(PAA)and a cationic bolaamphiphile(DBON),we explore the states of PECs as a function of salt,temperature,and the molecular weight of PAAs.By a combination of microscopic observation,time-resolved fluorescence measurements,and differential scanning calorimetry,we identify salt/temperature driven precipitate-to-coacervate transitions of the complexes.The thermally induced morphology transformation from the precipitate to coacervate occurs around the glass transition temperature,indicating a strong correlation between the two processes.As the molecular weight of the PAA increases,the thermal transition temperature becomes higher.This finding offers new insights on the mechanistic interactions that dictate the aggregated states of PECs.Based on the photothermal effect of DBON,we also develop a UV light-induced strategy to mediate the precipitate-to-coacervate transition,providing a fantastic platform to create functional PEC materials.

Tracking interactions between TAMs and CAFs mediated by arginase-induced proline production during immune evasion of HCC

Synergistic changes between tumor-associated macrophages(TAMs)and cancer-associatedfibroblasts(CAFs)aggravated immune evasion of hepatocellular carci-noma(HCC),however,the underlying molecular mechanisms remain elusive.Their continuous and dynamic interactions are subject to bioactive molecule changes.A real-time and in situ monitoring method suitable for in vivo research of these processes would be indispensable but is scarce.In this study,a dual imaging strat-egy that tracing the TAMs and CAFs simultaneously was developed using a new arginase-specific probe and established CAFs-specific probe.The emerging roles of arginase in mediating CAFs activation in mice were explored.Results showed arginase up-regulation in TAMs,followed by proline increase.Subsequently,proline produced by TAMs initiated the activation of CAFs.Through the JAK-STAT sig-naling,CAFs up-regulated the PD-L1 and CTLA-4,ultimately promoting immune evasion of HCC.This study revealed a new mechanism by which TAMs and CAFs collaborate in immune evasion,providing new targets for HCC immunotherapy.

Photodynamic patterning of living bacterial biofilms with high resolutions for information encryption and antibiotic screening

Controlling the growth of bacterial biofilms in a specific pattern greatly enhances the study of cell-to-cell interactions and paves the way for expanding their biolog-ical applications.However,the development of simple,cost-effective,and highly resolved biopatterning approaches remains a persistent challenge.Herein,a pio-neering photodynamic biopatterning technique for the creation of living bacterial biofilms with customized geometries at high resolutions is presented.First of all,an outstanding aggregation-induced emission photosensitizer is synthesized to enable efficient photodynamic bacterial killing at a low concentration.By combining with custom-designed photomasks featuring both opaque and transparent patterns,the viability of photosensitizer-coated bacteria is successfully manipulated by control-ling the degree of light transmittance.This process leads to the formation of living bacterial biofilms with specific patterns replicated from the photomask.Such an innovative strategy can be employed to generate living bacterial biofilms composed of either mono-or multispecies,with a spatial resolution of approximately 24µm.Furthermore,its potential applications in information storage/encryption and antibi-otic screening are explored.This study provides an alternative way to understand and investigate the intricate interactions among bacteria within 3D biofilms,hold-ing great promise in the controlled fabrication of dynamic biological systems for advanced applications.

Viologen-based host–guest supramolecule with tunable intramolecular/intermolecular electron transfer chromism and dynamic fluorescence

Viologen,as a type of strong electron acceptor,is prone to undergo electron transfer(ET)and change color under external stimuli.However,due to the easy aggrega-tion of viologen molecules,they usually suffer from poorfluorescence emission in the condensed phase.Herein,a new viologen derivative of VioCl_(2)⋅2Cl(1^(2+)⋅2Cl)was designed and synthesized,in which thefluorescence was enhanced by intro-ducing Me-β-CD to weaken the interactions between viologen molecules.Then a viologen-based host-guest supramolecule of 1^(2+)@Me-β-CD was obtained by elec-trostatic interactions.Photo-/chemo-responded guest 1^(2+)supplies 1^(2+)@Me-β-CD,a green and dark purple caused by intramolecular and intermolecular ET.Further-more,1^(2+)@Me-β-CD displays an additional thermal responsive purple color.The triple chromic behaviors all exhibit excellent reversibility and cycling stability.As expected,1^(2+)@Me-β-CD exhibits strong photoluminescence(PL)in solid-liquid dual states,presenting an improved quantum yield(Φ)from 1^(2+)(Φ_(s)=0.37%,Φ_(1)= 16.74%)to=1^(2+)@Me-β-CD(Φ_(s)= 10.45%,Φ_(1)= 25.86%),and thefluores-=cence intensity can be dynamically modulated by light,heat,and acid/base vapors.The multi-responsive chromism and tunablefluorescence of 1^(2+)@Me-β-CD allow for potential applications in information security and smart windows.

The“paper anniversary”of Aggregate:An epic journey and an amazing milestone

In the traditionalWestern culture,the first anniversary of marriage was referred to as a paper anniversary:paper is the top gift for the first-anniversary celebration.Time flies and it is now the time to celebrate the first-year birthday of Aggregate.The spotlight of this anniversary celebration is also papers,not the commodity papers sold in the markets but the research papers published in Aggregate.Since the first batch of research papers published in its inauguration issue at the end of last year,Aggregate has witnessed a challenging,thrilling yet fruitful year.Overcoming the negative impact of the coronavirus pandemic on scientific research,Aggregate has made an exotic journey and reached a magnificent milestone.

Chemiluminescence:From mechanism to applications in biological imaging and therapy

Chemiluminescence(CL)is an emission phenomenon induced by chemical reaction.Different from the photoluminescence,CL is free from external excitation source,which is expected to show great advantages such as higher signal-to-background ratio(SBR)in bioimaging,and deeper tissue penetration in photodynamic therapy(PDT).This review introduces the theoretical aspects of CL mechanism,such as classification,energy consideration and chemiexcited/photoexcited states.Application of CL in bioimaging is highlighted.In particular,the approaches to modulate the brightness and the wavelength of CL are summarized,which are two fundamental parameters in bioimaging.Finally,the application of CL in PDT is introduced.The potential challenges and perspectives of CL in bioimaging and therapy are also discussed.

Spatiotemporally controlled emergence of nanoparticle microvortices under electric field

Controlled assembly of nanoparticles(NPs)has garnered much interest over the past two decades.Beyond established techniques,new methods utilizing local short-range or large-scale long-range interactions remain to be explored to achieve diverse micro-and nanoscale structures.Here,we report the controlled emergence of vortex-pair arrays within monodispersed gold nanorods by applying a direct current electric field across a pair of sawtooth electrodes.By employing in situ darkfield microscopy and particle collective analysis,we elucidate the mechanism behind the formation and stabilization of the NP vortices,attributing it to the combined effects of the electrode shape,high NP density,and high solution viscosity.We further explore the controllability of the vortex-pair arrays and obtain multiple complex vortice patterns.Our findings will facilitate the investigation of efficient and controlled dynamic assembly of NPs under external fields and help manufacture next-generation optoelectronic functional materials.

An efficient photothermal conversion material based on D-A type luminophore for solar-driven desalination

Solar-driven interfacial evaporation is a promising technology for desalination.The photothermal conversion materials are at the core and play a key role in thisfield.Design of photothermal conversion materials based on organic dyes for desalina-tion is still a challenge due to lack of efficient guiding strategy.Herein,a new D(donor)-A(acceptor)type conjugated tetraphenylpyrazine(TPP)luminophore(namely TPP-2IND)was prepared as a photothermal conversion molecule.It exhib-ited a broad absorption spectrum and strongπ–πstacking in the solid state,resulting in efficient sunlight harvesting and boosting nonradiative decay.TPP-2IND powder exhibited high photothermal efficiency upon 660 nm laser irradiation(0.9 W cm^(-2)),and the surface temperature can reach to 200℃.Then,an interfacial heating system based on TPP-2IND is established successfully.The water evaporation rate and the solar-driven water evaporation efficiency were evaluated up to 1.04 kg m^(-2) h^(-1) and 65.8%under 1 sunlight,respectively.Thus,this novel solar-driven heating system shows high potential for desalination and stimulates the development of advanced photothermal conversion materials.

A NIR ratiometric fluorescent biosensor for sensitive detection and imaging of α-L-fucosidase in living cells and HCC tumor-bearing mice

Detection and imaging of α-L-fucosidase(AFU)is of great value to understand its roles in hepatocellular carcinoma(HCC)and tumor early diagnosis,but ideal assays are still lacking.Herein,a near-infrared(NIR)fluorescent biosensor(α-Fuc-DCM)was elaborately designed and synthesized for rapid and ratiometric detection of AFU activity in cells and HCC tumor mouse models.In the presence of AFU,this biosensor shows an enhancement in NIR emission in a ratiometric manner,which significantly improves the detection accuracy with the limit of detection as low as 4.8 mU/mL.Taking advantage of these merits,the activity of AFU in lysosomes could be visualized using ratiometric and NIR dual modality in living cells.Furthermore,its remarkable application for monitoring of endogenous AFU activity in HCC tumor-bearing mouse model is also demonstrated with bright fluorescence signal,which indicated that the biosensor could clearly monitor the liver tumor in the early stage.Importantly,the α-Fuc-DCM probe can be utilized to detect the AFU in serum from HCC patients.This strategy offers a promising biosensor system for early diagnosis of HCC and studying the roles of AFU in cancers.

From bud to blossom:The incredible journey of Aggregate

The days are long,but the years are short.This quote perfectly encapsulates my feelings as we mark the third anniversary of Aggregate.Over the past 3 years,Aggre-gate has been a steadfast companion to scientists,growing together with them in the field of research on aggregate science.On June 28,2023,Clarivate Analytics unveiled Jour-nal Citation Reports(JCR)2023 and Aggregate received its first Journal Impact Factor(JIF)of 18.8.This is a great milestone in the development of Aggregate.I am thrilled to witness that Aggregate has made further progress this year in terms of both the quantity and quality of published papers.