Fibrous Aerogels with Tunable Superwettability for High-Performance Solar-Driven Interfacial Evaporation

Solar-driven interfacial evaporation is an emerging technology for water desalination.Generally,double-layered structure with separate surface wettability properties is usually employed for evaporator construction.However,creating materials with tunable properties is a great challenge because the wettability of existing materials is usually monotonous.Herein,we report vinyltrimethoxysilane as a single molecular unit to hybrid with bacterial cellulose(BC)fibrous network,which can be built into robust aerogel with entirely distinct wettability through controlling assembly pathways.Siloxane groups or carbon atoms are exposed on the surface of BC nanofibers,resulting in either superhydrophilic or superhydrophobic aerogels.With this special property,single component-modified aerogels could be integrated into a double-layered evaporator for water desalination.Under 1 sun,our evaporator achieves high water evaporation rates of 1.91 and 4.20 kg m^(-2)h^(-1)under laboratory and outdoor solar conditions,respectively.Moreover,this aerogel evaporator shows unprecedented lightweight,structural robustness,long-term stability under extreme conditions,and excellent salt-resistance,highlighting the advantages in synthesis of aerogel materials from the single molecular unit.

Review:Aggregation-Induced Emission——A New Tool to Study Polymer Thermodynamics and Kinetics

Polymer thermodynamics and kinetics are important components in the basic theory of polymer physics, which provide critical support for polymer processing and molding. As an important thermal analysis technology, differential scanning calorimetry(DSC) is a key way to explore the molecular motion of polymer chains, molecular structure, and condensed structure, greatly promoting the development of polymer materials. However, this technique is limited by its ambiguous results, because of inaccurate heat flow measurement and high parameter dependence. As an alternative strategy, aggregation-induced emission luminogens(AIEgens) have been extensively applied in various targets analysis and process monitoring, owing to their weak intermolecular interactions and highly twisted conformation. The optical properties of AIEgens are highly sensitive to the variations of the polymer microenvironment, including characteristic transition, crosslinking reaction, crystallization behavior, and phase separation. In this review, the progress of AIE technology in visualizing polymer molecular motion and structure evolution is summarized, compensating for the limitation of the traditional DSC method to facilitate further research in polymer science and engineering.

Polymer-based hybrid materials and their application in personal health

With unprecedented properties and functions,polymer-based hybrid materials hold extremely important position in many fields.Here in this review,we summarized applications of polymer-based hybrid materials toward personal health.Firstly,theoretical calculation and in-situ visualization used to explore the interfacial interaction and formation of hybrid materials are introduced.Secondly,applications of polymer-based hybrid materials in personal health from proactive protection(anti-bacteria and harmful gas removal),health condition monitoring(breathing and sleep)to disease diagnosis(magnetic resonance imaging),and tissue therapy(dental restoration)are discussed.Additionally,aggregation-induced emission(AIE)organic molecules based optical sensors for personal security and polymer semiconductor for organic thin film transistors are simply discussed.Finally,we present the future tendency for preparing polymer-based hybrid materials that related with personal health.

Confinement fluorescence effect of an aggregation-induced emission luminogen in crystalline polymer

Despite the impressive progress of stimuli-responsive fluorescent materials,little is known about the influence of confinement created by crystalline polymer over the fluorescence properties of fluorescent molecules.The effects of confinement on the fluorescence of an aggregation-induced emission luminogen(AIEgen)are investigated using computational simulations,which reveal that the confined space induces the AIEgens to take a more planar conformation,resulting in a red-shifted emission spectrum.With this property,the study is extended to explore the confinement generated by various polymer crystalline forms,and it is shown that different fluorescence colors are activated.This confinement fluorescence effect is attributed to the different spatial dimensions of the polymer amorphous layer between lamellar crystals where the AIEgens are located.These results indicate the immediate association between crystalline structure and fluorescence signals,activating unprecedented photophysical properties of luminescent materials,and also providing the possibility for crystalline structure visualization,it is important for the many polymer crystallization processes occurring in the materials processing.

Visual Detection of COVID‑19 from Materials Aspect

In the recent COVID-19 pandemic,World Health Organization emphasized that early detection is an effective strategy to reduce the spread of SARS-CoV-2 viruses.Several diagnostic methods,such as reverse transcription-polymerase chain reaction(RT-PCR)and lateral flow immunoassay(LFIA),have been applied based on the mechanism of specific recognition and binding of the probes to viruses or viral antigens.Although the remarkable progress,these methods still suffer from inadequate cellular materials or errors in the detection and sampling procedure of nasopharyngeal/oropharyngeal swab collection.Therefore,developing accurate,ultrafast,and visualized detection calls for more advanced materials and technology urgently to fight against the epidemic.In this review,we first summarize the current methodologies for SARS-CoV-2 diagnosis.Then,recent representative examples are introduced based on various output signals(e.g.,colorimetric,fluorometric,electronic,acoustic).Finally,we discuss the limitations of the methods and provide our perspectives on priorities for future test development.

Structural design of light-emitting fibers and fabrics for wearable and smart devices

Flexible light-emitting fibers and fabrics serve to bridge human–machine interactions. The desire for practical applications and the commercialization of flexible light-emitting fibers has accelerated structural progress and improvements. This review focuses on the structural design of light-emitting fibers and fabrics, starting with a summary of design principles, emission mechanisms, and structural evolution of coaxial structured light-emitting fibers. Subsequently, we explore recent advances in the helical structure design strategies that boost the mechanical sensitivity of light-emitting fibers. Following that, we analyze continuous preparation processes and the development of large-area intelligent light-emitting fabrics based on interwoven structures. Examples based on stiff and rigid inorganic-based lightemitting diodes integrated into flexible systems are also presented. Finally, we discuss the current challenges and future opportunities for light-emitting applications in the field of wearable and smart devices.