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Benzoxazines, renowned for their self-curing properties, high glass transition temperature, and exceptional thermal stability, have faced environmental and biotoxicity concerns despite their remarkable performance. Combining high-performance, ecofriendly and degradable benzoxazines remains a challenge. In this work, we synthesized an entirely bio-based benzoxazine resin, 2,6-bis(3-(furan-2-ylmethyl)-8-methoxy-2-phenyl-3,4-dihydro-2H-benzo[e][1,3]oxazin-6-yl)tetrahydro-[1,3]dioxino[5,4-d][1,3]dioxine (VE-BZ), from natural raw materials, including vanillin, erythritol, furfurylamine, and natural benzaldehyde. The presence of the bis(acetal) structure, furanic structure, and benzene ring-branched chain structure in the resin confers favorable adhesive strength, high carbon residue, self-extinguishing ability, and outstanding thermal stability to VE-BZ. Moreover, VE-BZ can undergo dual-site curing and complete degradation through the synergistic effects of acid and heat, enabling its reuse in benzoxazine synthesis. The acid used for both synthesis and degradation is bio-based citric acid, eliminating non-biobased catalysts or additives from the entire process. This approach embodies a comprehensive green chemistry closed-loop process. In essence, this research offers valuable perspectives on seamlessly combining exceptional performance with eco-friendly attributes in the realm of benzoxazine resin materials. [ABSTRACT FROM AUTHOR]

Cubic nanoparticles of CeO2 were partly covered on the tetrahedron surface of γ-Bi2O3 through a hydrothermal reaction and then a calcination process to construct a novel S-type γ-Bi2O3/CeO2 heterojunction. The optimized sample removed 96% of lomefloxacin and 81% of tetracycline. During the cycling test, the photocatalytic efficiency of lomefloxacin and tetracycline was maintained above 87% and 80%, respectively, for five consecutive cycles. According to XRD and Raman spectra characterization, the sample after cycling held a stable crystal structure. Holes, OH−˙, O2˙, and electrons participated in the degradation of lomefloxacin, while tetracycline was removed via the effect of the former three active substances. Based on theoretical calculation and experimental tests, the excellent photocatalytic activity of γ-Bi2O3/CeO2 came from the fast transfer of charge carriers along the S-type path. Moreover, the CB electrons of γ-Bi2O3 and VB holes of CeO2 were preserved to generate free radicals for antibiotic degradation. The colony numbers of Escherichia coli were 1.50 × 10−6 CFU mL−1 and 1.39 × 10−6 CFU mL−1 in solutions after the degradation of the two pollutants, which represents the non-toxicity of the final products. The γ-Bi2O3/CeO2 sample has a potential application for antibiotic removal from modern sewage. [ABSTRACT FROM AUTHOR]

Advanced microwave absorption materials (MAMs) are required to have strong attenuation capability, intelligent manufacturing, and robust environmental adaptivity for diversified application scenarios. However, the effective integration of multifunctionality in single MAMs is still unprecedented challenge. Herein, the synergistic strategy of in situ growth, C–F⋯π interaction, and microwave irradiation was proposed to fabricate CoM@CoNiC–F nanocomposite. The polarity-induced rigid-flexible epoxy/multifluorination/siloxane networks were chosen as supporting materials, and the bi-continuous phase separation mechanism was clarified. Moreover, the high-resolution and complex 4D-printed objects were obtained by the DIW technology, and it also exhibited reliable dynamic evolution behavior with photo-/thermal-induced shape memory. Furthermore, the absorber exhibited excellent RLmin (−64.78 dB) and wide EAB (4.6 GHz), which was consistent with the RCS simulation results, and it benefited from optimized impedance matching and multiple magnetic–dielectric coupling. Remarkably, the MAMs simultaneously possessed robust protective-multifunctionalities with excellent mechanical, superamphiphobicity, long-term anticorrosion, and flame retardancy performance. This strategy provided an advisable guideline for designing intelligent MAMs and created infinite feasibility in sophisticated and dynamic electromagnetic wave absorption field. [ABSTRACT FROM AUTHOR]

The development of multifunctional electromagnetic wave (EMW) absorption materials is important for addressing the hazards posed by EMWs. Herein, we designed a polyurethane-based EMW absorption material (P6H7-B3O3-CoNC@rGo6%) with high strength, self-healing ability and highly efficient EMW absorption properties. The P6H7-B3O3-CoNC@rGo6% shows excellent EMW absorption performance with a minimum reflection loss (RLmin) of −47.1 dB at 12.8 GHz, an effective absorption bandwidth (EAB) of 4.11 GHz at 2 mm thickness and a very low filler mass loading of only 6 wt%. The polyurethane (P6H7-B3O3) and the nanocomposites (P6H7-B3O3-CoNC@rGo6%) exhibit excellent mechanical properties with tensile strength of 62.79 MPa and 22.04 MPa, respectively. Additionally, the P6H7-B3O3-CoNC@rGo6% can rapidly restore to its original state at 85 °C by the ester exchange reaction of boron ester bonds. This strategy provides a new idea for designing polyurethane-based EMW absorption materials and extending the service life of EMW absorption materials. [ABSTRACT FROM AUTHOR]

It is a challenge to develop polyurea with high-performance and multifunctionality because the integration of functions often comes at the expense of mechanical properties. This work synthesized a novel diisocyanate with a pyrene side chain, followed by reacting with poly(propylene oxide) diamine to prepare polyurea elastomers (PPU-x). Herein, thanks to the strong π–π stacking effect between pyrene groups and the anchoring effect of the amino group, the maximum tensile strength of PPU-x reached 41.4 MPa. The large conjugate structure of pyrene groups also gave PPU-x outstanding fluorescence and UV shielding performance. More noteworthy is the fact that graphene can be well dispersed in PPU-x with such high polarity via π–π interactions, which caused the dielectric constant of graphene-modified PPU-x nanocomposites to be three times that of PPU-0.3. Furthermore, this nanocomposite was used to make a triboelectric nanogenerator. Under the action of 0.5 N, the output voltage can reach 80 V, which is expected to be used to monitor weak signals of the human body. This work opens up a new strategy for the development of high-performance polyurea and its graphene-modified multifunctional polyurea nanomaterials with wide potential applications. [ABSTRACT FROM AUTHOR]

The Bi2MoO6 nanosheets are loaded on to γ-Bi2O3 tetrahedron surfaces to form Bi2MoO6/γ-Bi2O3 heterojunctions using a simple calcination method. The photocatalytic degradation efficiencies of the lomefloxacin and the Rhodamine B using the optimum sample are 96% and 99%, respectively, much higher than that of pure phase samples. When the waters from different regions in China were used as solvents, the removal efficiencies of the lomefloxacin and the Rhodamine B are still higher than 88% and 90%, respectively, which shows excellent prospects for practical applications. The photocatalytic degradation efficiencies of these two pollutants are higher than 91% and 95% in the five cycling tests, and the crystal structure of the sample is not changed after cycling. Based on the first-principles calculation, Bi2MoO6 and γ-Bi2O3 form a Z-type energy band structure which accelerates the separation of the photogenerated charge carriers. The Bi2MoO6 valence band potential of 3.25 V and the γ-Bi2O3 conduction band potential of −0.21 V are reserved to generate ˙OH− and O2−, respectively, for the photocatalytic reaction. The degradation of the lomefloxacin is ascribed to the shedding of functional groups and bond breaking with the final products being CO2, F−, H2O, and NO3−. This research shows that Bi2MoO6/γ-Bi2O3 heterojunctions can be employed to purify domestic and textile industrial sewage. [ABSTRACT FROM AUTHOR]

Construction of direct Z-scheme photocatalytic heterojunctions with an internal electric field has been proposed as an outstanding method to achieve efficient utilization of solar energy for photocatalytic overall water-splitting. In this work, the properties of van der Waals (vdW) heterojunctions formed by group-IV mono-chalcogenides (MXs) (M = Ge, Sn; X = S, Se, Te) and MoS2 are systematically studied by first-principles calculations, including the vdW binding energy, the direction of an internal electric field and the electronic structure. The results predict that GeS/MoS2, GeSe/MoS2 and SnS/MoS2 vdW heterojunctions are potential direct Z-scheme water-splitting photocatalysts with appropriate band alignments, a wide light absorption range and low effective charge-carrier mass. Furthermore, the hydrogen evolution reaction (HER) and the oxygen evolution reaction (OER) activities of the heterojunctions as photocatalysts are predicted. The results indicate that SnS/MoS2 with the Sn vacancy has a low Gibbs free energy of the HER (0.06 eV), and MoS2 with the S edge can offer OER active sites. This study provides a theoretical basis for the further design and preparation of a new two-dimensional overall water-splitting photocatalyst, which is conducive to the development of efficient two-dimensional photocatalysts in the field of clean energy. [ABSTRACT FROM AUTHOR]

Nanostructured β-Bi2O3 was synthesized and used for the photocatalytic degradation of bisphenol A and phenol. After 90 minutes of sunlight irradiation, the degradation efficiencies toward bisphenol A and phenol were 96% and 97%, respectively. Changes in sunlight due to the season and the calcination temperature and duration displayed weak influence on the degradation efficiencies for these two pollutants. Although the use of tap water, river water, lake water, and seawater exhibited a certain impact on the photocatalytic efficiency, the final removal efficiencies for bisphenol A and phenol in seawater still reached 89% and 90%, respectively. Moreover, the photocatalytic efficiencies toward bisphenol A and phenol remained above 91% and 86% during testing over five cycles. Superoxide groups (O2−) and holes were the main active substances, while hydroxyl radicals (˙OH−) also played a certain role in photocatalysis. The charge-carrier concentration and mobility of β-Bi2O3 were 4.82 × 1021 cm−3 and 4.0017 cm2 V−1 s−1, respectively, based on the Hall test. β-Bi2O3 was an isotropic semiconductor based on first-principles calculations, and its excellent photocatalytic activity originated from the high electron mobility and moderate hole mobility. The bisphenol A and phenol degradation mechanisms on the β-Bi2O3 surface were revealed based on adsorption model calculations. Finally, the reduction in total organic carbon content further verified the degradation of these two contaminants. [ABSTRACT FROM AUTHOR]

Monoclinic Lu2WO6 undergoes diphase-to-perovskite BiLuWO6 transition via selective occupancy of Bi in three Lu sites. The transformation mechanism, process, and structure stabilities are revealed by variable cell nudged elastic band method, video, and phonon spectrum. Lattice transition brings about photogenerated charge separation in BiLuWO6. This is verified by indirect band gap transition, high electron migration rate, weak exciton binding energy, large photocurrent response, and small impedance. The electron–hole life time is elongated to produce abundant superoxide and hydroxyl radicals for the degradation of rhodamine B and phenol molecules. Bi–O antibonding states serve as immediate energy levels to change the recombination path, inducing 340 nm excitation band and 510 nm green light emission of Lu2WO6. Furthermore, multicolor emission of 1 at% Bi3+ + RE3+ (RE = Sm/Eu/Dy)-codoped Lu2WO6 is acquired via synergistic modification of the Bi–O antibonding state and RE3+ 4f states. Thus, the photogenerated charge motion in Lu2WO6 is tuned to expand application fields. [ABSTRACT FROM AUTHOR]

The chemical state of Pt in cocatalysts has a major influence on the activity and selectivity of the photocatalytic reduction of CO2; however, the underlying mechanism is unclear owing to the co-existence of different Pt chemical states and mutual transformation between them. In this study, PtO/TiO2 catalysts were prepared through photodeposition and Pt/TiO2 was prepared by the photoreduction of PtO/TiO2 to avoid interference arising from co-existing Pt forms and different loading amounts. These catalysts exhibited completely reversed selectivity for CO and CH4 production during CO2 photoreduction: PtO/TiO2 tended to produce CO (100%), whereas Pt/TiO2 favored the production of CH4 (66.6%). By combining experimental analysis and theoretical calculations, the difference in selectivity was ascribed to the different charge transfer/separation and CO/H adsorption properties of PtO/TiO2 and Pt/TiO2. Photoelectric and photoluminescence (PL) analysis showed that Pt was more advantageous to the photogenerated carrier separation compared with PtO, which was conducive to the multi-electron CH4 reduction reaction. Fourier transform-infrared spectroscopy, temperature-programmed desorption/temperature-programmed reduction, and density functional theory calculations indicated that the adsorption of CO and hydrogen on Pt was stronger than that on PtO, which favored the further reduction of CO to CH4. Based on the above results, a mechanism was proposed to explain the reversed selectivity of the photocatalytic reduction of CO2 over Pt/TiO2 and PtO/TiO2. [ABSTRACT FROM AUTHOR]

Multi-responsive form-stable phase change materials (FSPCMs) can convert various forms of energy to latent heat for storage and have attracted extensive attention. Superhydrophobic surfaces are garnering constant interest and can improve the long-term solar energy utilization and environmental adaptability of multi-responsive FSPCMs. However, a simultaneous demonstration of such functional integration is still a challenge due to the restriction of supporting materials. Herein, crosslinkable bottlebrush crystalline polysiloxanes (Si0.75-18-x) having strong intermolecular forces with paraffin are used as super-flexible supporting materials to encapsulate paraffin via self-assembly and 3D networks. Multi-responsive phase change films are directly fabricated by spray-coating Si0.75-18-x/paraffin solution with a dispersion of multi-walled carbon nanotubes (MWCNTs), followed by in situ curing. Herein, apart from fine affinity with Si0.75-18-x, MWCNTs simultaneously enable tailored surface roughness, thermal/electrical conductivity and photo-thermal conversion. The proof-of-concept material (SiPa-160/CNTs-3) shows excellent latent heat, superhydrophobicity, photonic/thermal/electrical responses, shape variation ability, thermal recycling properties and stability. Strikingly, SiPa-160/CNTs-3 coatings can be large-scale constructed on varied substrates and have the potential for use in wearable devices, intelligent buildings, electronic devices and so on. This study broadens the advanced application and creates a whole new development platform for FSPCMs in energy conversion and storage. [ABSTRACT FROM AUTHOR]

Designing photocatalysts with appropriate intrinsic active sites for the hydrogen evolution reaction (HER) and efficient charge-carrier separation is critical to get rid of the dependence on co-catalysts. Herein, we for the first time trigger the catalytic activity of inert basal plane S atoms in two-dimensional hexagonal ZnIn2S4 (ZIS) via Ni atom doping (Ni-ZIS). Density functional theory calculations (DFT) and X-ray absorption fine structure (XAFS) investigations reveal that Ni atoms preferably replace Zn atoms in ZIS. And introducing Ni atoms would form new hybridized states near the Fermi level and modulate the electronic properties of their neighboring S atoms, leading to optimized hydrogen adsorption free energy and enhanced HER kinetics. Additionally, fs-transient absorption spectroscopy measurements illustrate a prolonged recovery lifetime of photoexcited electrons in Ni-ZIS. Consequently, Ni-ZIS exhibits an improved photocatalytic activity with a hydrogen evolution rate of 4220 μmol g−1 h−1 under visible light irradiation (λ > 420 nm) without any co-catalysts, roughly 3.2 times higher than that of ZIS. The apparent quantum efficiency at 380 and 420 nm could reach as high as 19.7% and 17.1%, respectively. This single atom modulation strategy presents a facile and promising pathway to enhance the photocatalytic activity of ZIS for the HER without co-catalysts. [ABSTRACT FROM AUTHOR]

Reticulated copolymer host pillar[5]arene cross-linked with poly(dimethylsiloxane) (PDMS) was synthesized for the facile construction of a double network cross-linked elastomer upon noncovalently cross-linking with tetraphenyethylene (TPE)-based tetratopic guests through host–guest interactions. The obtained sample strips had better mechanical properties and luminescence capabilities. [ABSTRACT FROM AUTHOR]

Rh1/CeO2 single-atom catalyst is highly active for CO oxidation and has the potential to serve as a multifunctional catalyst to save the usage of other noble metals in three-way catalysts. The high activity is achieved on single-atom active sites via the Mars–van Krevelen mechanism, thus avoiding CO poisoning at low temperatures. [ABSTRACT FROM AUTHOR]

A tetrapyridine-decorated tetraphenylethene (TPE) ligand 1 was designed, which, upon interacting with silver ions, displayed "turn-on" fluorescence in a dilute solution. The fluorescence enhancement can be attributed to the cooperative effect of restriction of the intramolecular rotation by metal coordination and silver ion induced aggregation. Furthermore, the fluorescence turn-on performance of AIE molecules in a dilute solution leads to tunable fluorescence properties including white-light emission by simply mixing AIE and ACQ molecules together, which might bridge the gap between the AIE and ACQ phenomena for the construction of color-tunable fluorescence systems. [ABSTRACT FROM AUTHOR]

Designing a fully biobased monomer to build a series of degradable thermosets is of great significance for sustainable development and environmental protection. In this work, a fully biomass based monomer (EUIT) was designed and synthesized from itaconic acid (IA) and eugenol (EU). Thiol–ene crosslinked polymers (TCPs) were prepared by changing the degree of the thiol functionality from 2 to 4 via a VOC-free thiol–ene click reaction. Also, the thermal, thermomechanical, and mechanical properties of these TCPs were investigated. The results showed that EUIT/4SH possessed the best comprehensive properties, that is, the glass-transition temperature (Tg) was up to 74.0 °C, and the mechanical properties including tensile strength and modulus were 58.6 MPa and 1.5 GPa, respectively, which were the maximum values compared with those in the reported investigations. Besides, these TCPs exhibited good degradable properties because of the inherent functional groups such as the ester groups in EUIT. Thus, this study provides a new method to prepare a fully biobased monomer and produce a series of degradable thermosets which are expected to be advanced biomedical materials, flexible electronic materials, etc. [ABSTRACT FROM AUTHOR]

Monolayer MoS2 has emerged as an active and non-precious electrocatalyst for electrochemical hydrogen production. The atomic thinness and ultrahigh surface-to-volume ratio of the chemical vapor deposition (CVD)-grown monolayers result in an ideal material to facilitate efficient electrochemical hydrogen evolution and explore the mechanism at the atomic level. However, the active sites of pristine monolayer MoS2 are reported to locate at the edges, leaving the basal planes inert, which limits their hydrogen evolution reaction performance. Here, we synthesize monolayer MoS2 hexagonal flakes with high surface coverage and abundant highly distributed S vacancies as active reaction sites directly by CVD. The catalytic performance of the hexagonal MoS2 flakes presented here is superior to that of the existing as-grown MoS2, exhibiting a current density of 100 mA cm−2 at −353 mV versus the reversible hydrogen electrode (RHE) with an extraordinarily low onset potential of only 41 mV. And an outstanding exchange current density of 0.091 mA cm−2 stands as the highest ever reported for all kinds of non-precious-metal doped MoS2 catalysts. It is proved by a variety of tests that abundant S vacancies are distributed in the highly crystalline basal plane of hexagonal MoS2, which leads to a remarkably improved catalytic efficiency compared with that of the triangular one. The monolayer MoS2 is further evidenced to have excellent long-term stability and high durability, maintaining a stable performance for nine months in air and retaining the initial performance after 6000 cyclic voltammetry scans. On-site defect engineering of monolayer MoS2 for excellent hydrogen evolution reaction (HER) performance enriches insights into the structure–performance relationship in 2D materials and provides new opportunities for the design of highly active catalysts. [ABSTRACT FROM AUTHOR]

Smart luminescent materials can substantially alter their physicochemical properties with various stimuli and thus have long been a point of interest for the development and manufacture of various commodities. In particular, photoresponsive materials have seen much commercial success as sensors and for applications in the paint and coating industry. Herein, we report the design, synthesis, and material processing of a novel alkynylpyrene derivative. The aggregation behavior of this compound can be fine tuned in response to different conditions, such as solvent polarity, concentration, and ratio of good solvents to poor solvents. In addition, the concentration-dependent 1H NMR spectroscopic study and single crystal structure of the model compound revealed that multiple weak intermolecular interactions might be responsible for the formation of highly ordered aggregates. With the formation of highly ordered aggregates through molecular self-assembly, photodimerization can be realized effectively with 400 nm LED irradiation. Owing to the invisible and controlled printable characteristics of the aggregates and the conversion process of the luminescent material, we have demonstrated that our platform can act as a smart luminescent system towards confidential information encryption and decryption with various high-resolution patterns by photolithography and inkjet-printing techniques. In addition, the inherent molecular packing of the materials allows us to quench the luminescence of the as-printed characters easily upon blue visible light irradiation and realize the irreversible erasure of the luminescence signal for multiple information rewritable processes. As a result, the present luminescent material will find applications in the fields of optical information storage, information security protection, and erase/rewrite systems and provide a proof-of-principle application. [ABSTRACT FROM AUTHOR]

Coarse-grained (CG) molecular dynamics simulations have been employed to study the thermo-mechanical response of a physically cross-linked network composed of zwitterionic moieties and fully flexible elastomeric polymer chains. In this work, we used the effective Lennard-Jones interactions for our bead-spring model of zwitterionic cross-linkers (ZCLs). The effects of ZCL functionality, its chain length and the attractive interaction strength (ε) of end-groups on the thermo-mechanical properties are explored. We developed one particular system with versatile functionality of ZCLs at constant molecular weight with variable functional sites, observing that the stress–strain curve is increased with the functionality, evidenced by the bond orientation through the second-order Legendre polynomials. In the case of the length of the tri-functional ZCL, we found that a shorter length leads to a higher modulus and a relatively greater value of glass-transition temperature (Tg). In addition, we found that with the increase of the attractive interaction strength (ε) on the tri-functional ZCL, the stress–strain behaviour and the chain orientation are reinforced, accompanied by an enhancement of Tg. Lastly, we examined the effect of the cross-linker functionality on the tension–recovery process, as well as the fracture behaviour, by performing the typical tri-axial deformation. The results of tension–recovery and tri-axial deformation correspondingly proved the presence of physical linkages of end-groups, and strong attractive forces between end-linking groups were revealed through visual molecular dynamics (VMD) analysis. Generally, we anticipate that our work could provide some guidelines for the rational design and preparation of high performance zwitterionic cross-linked elastomeric materials. [ABSTRACT FROM AUTHOR]

Copper cysteamine (Cu–Cy) is a new type of photosensitizer, which can be activated not only by ultraviolet light, but also by X-rays, microwaves and ultrasound to generate reactive oxygen species for treating cancer and infection diseases. Moreover, copper cysteamine has a strong luminescence, which can be used for both therapeutics and imaging. In addition, it can also be used for solid state lighting, radiation detection and sensing. However, its electronic structures, and particularly its excited states, are not yet clear. Here, we present a computational study aiming to determine the nature of the excited states involved in the photophysical processes that lead to the luminescence of this compound. This study has been conducted using density functional theory (DFT), using both hybrid functionals and time-dependent DFT. It is found that both absorption and emission involve the replacement of an electron among the 3d and 4s orbitals of one or the other of the two types of Cu atoms found in the system. Our computed results compared well with the experimental absorption and emission results. These results are very helpful for the understanding of the experimental observations. [ABSTRACT FROM AUTHOR]

One great challenge of lithium-ion battery (LIB) commercialization is to achieve high rate capacity at large mass loading density. Here, a thermal-convection hydrothermal method was newly designed and developed to synthesize TiO2 microclews (TiO2 MCs) for their use as LIB electrode materials. The unique MC architecture could be immobilized on a carbon cloth collector uniformly to form a 3D flexible conductive network (TiO2 MCs@CC), which facilitates fast Li-ion and electron transport and promotes continuous lithiation reaction during the charge–discharge process. With these merits, TiO2 MCs@CC with high loading density (up to 4 mg cm−2) exhibits ultra-high rate performance (75 mA h g−1 at an extremely high current density of 4000 mA g−1), outstanding long-cycling life (74 mA h g−1 over 1000 cycles at a specific current density of 2000 mA g−1) and a high initial coulombic efficiency (ICE) of 82%. The demonstrated advantages open up possibilities for fabricating ultrafast rechargeable LIBs with potential industrial applications. [ABSTRACT FROM AUTHOR]

The preparation of highly incompatible interpenetrating polymer network systems with a high extent of phase mixing has been a challenging task because the thermodynamics of phase separation are so powerful. Here, we propose a facial strategy to design a ‘forced’ intermixing epoxy/polysiloxane network by utilizing a novel epoxy/polysiloxane monomer (SH-EP) in a one-pot synthesis. The relationship between the structure and properties is systematically investigated using FTIR spectrometry, rheology, SEM, and DMA. Impressively, the epoxy and polysiloxane networks can be driven to closely interpenetrate by their intrinsic motive force derived from the ‘forced’ sites in SH-EP, which in turn, may easily give rise to a bicontinuous morphology. In addition, the gelation time is systematically controlled by varying the polysiloxane content and pre-curing temperature. By tuning the gelation time, the extent of phase mixing and the degree of phase separation can be further regulated. The result is striking: for the first time, these highly incompatible epoxy/polysiloxane intermixing networks exhibit ultralow-temperature damping properties (tan δ ＞ 0.3) over a very broad temperature range of 217 °C (from −114 °C to 103 °C). This finding may revolutionise the frontiers of materials knowledge. [ABSTRACT FROM AUTHOR]

Room-temperature-use phase change materials (PCMs) are of vital importance in combining the sustainable development of energy with human comfort. Here, a series of novel epoxy-based polymeric solid–solid PCMs (SSPCMs) were facilely prepared by UV grafting 1-octadecanethiol (ODT) onto an allyl-based epoxy resin (DADGEBA) via thiol–ene click chemistry followed by the epoxy–amine thermal curing process. Therefore, the grafted ODT can be tightly locked in a reliable three-dimensional crosslinking network of the epoxy resin, which provides the PCMs with excellent shape-stable property. Phase change and mechanical properties characterized by DSC, DMA, hardness test, and tensile test can be easily tuned by adjusting the mass ratio of DGEBA and the ODT-grafted-DADGEBA product (D18), which was characterized by FTIR and NMR. XRD and POM analyses proved the crystallinity of EPD18-X PCMs. The structure and morphology of the EPD18-X PCMs were characterized by visual images, SEM, and POM analyses. Microphase separation was observed in all the EPD18-X PCMs, and an obvious phase separation was observed in the EPD18-25 system. However, the phase separation gradually disappeared with the increasing of the D18 content. Thermal recycling tests showed that EPD18-X PCMs can remain stable after 50 DSC thermal cycles. Due to the unique strong encapsulated epoxy curing networks, EPD18-X PCMs have excellent thermal stability with the onset degradation temperature higher than 250 °C. Tunable EPD18-X systems can be applied for room-temperature-use thermal energy storage applications such as buildings, thermoregulated fabrics, and so on. [ABSTRACT FROM AUTHOR]

Formation of surface heterojunctions in photocatalysts through tailoring the exposed crystal facets is an efficient strategy to boost charge separation. In this work, successive surface heterojunctions with large space-charge separation were achieved in a nanostep structured La2Ti2O7 (LTO NSP) single crystal exposed periodically with (010) and (012) facets. The three-dimensional (3D) nanosteps were found to enhance the photocatalytic hydrogen generation performance 35 and 74 times, compared with LTO nanosheets and nanoparticles with the same surface area, respectively. The ultrahigh superficial charge accumulation in LTO NSP verified by surface photovoltage (SPV) measurements suggested the efficient migration of photogenerated charge carriers to the surface. Femtosecond time-resolved diffuse reflectance (TDR) spectroscopy provided direct evidence that the electrons generated from the excited sites of LTO NSP were effectively delivered to the high energy (012) facets and temporarily stored there for further reduction reactions, originating from the successive (010) and (012) surface heterojunctions. [ABSTRACT FROM AUTHOR]

Polymeric micelles loaded with chlorin e6 and Tanshinone I (TAS) were prepared and employed for photodegrading amyloid β (Aβ) aggregates and inhibiting Aβ fibrillation. [ABSTRACT FROM AUTHOR]

It is known that the combination of TiO2 and graphene and the control of TiO2 crystal facets are both effective routes to improve the photocatalytic performance of TiO2. Here, we report the synthesis and the photocatalytic CO2 reduction performance of graphene supported TiO2 nanocrystals with coexposed {001} and {101} facets (G/TiO2-001/101). The combination of TiO2 and graphene enhanced the crystallinity of TiO2 single nanocrystals and obviously improved their dispersion on graphene. The “surface heterojunction” formed by the coexposed {001} and {101} facets can promote the spatial separation of photogenerated electrons and holes toward different facets and the supports of graphene can further enhance the separation through accelerated electron migration from TiO2 to graphene. The G/TiO2-001/101 exhibited high photocatalytic CO2-reduction activity with a maximum CO yield reaching 70.8 μmol g−1 h−1. The enhanced photocatalytic activity of the composites can be attributed to their high surface area, good dispersion of TiO2 nanoparticles, and effective separation of excited charges due to the synergy of graphene supports and the co-exposure of {001} and {101} facets. [ABSTRACT FROM AUTHOR]

Hierarchical tungsten oxide nanostructures, controllably assembled with one-dimensional nanosized building blocks, which exhibit different exposed facets and crystal phases were synthesized via a facile hydrothermal reaction assisted by urea. Systematic and comprehensive investigations indicate that urea plays a significant role in tuning the exposed facets of the building blocks and controlling the crystal phase by effectively regulating the process of nucleation. By adjusting the amount of urea, a suitable crystal phase can be obtained and the exposed facets can be tuned to achieve the highest photocatalytic activity of tungsten oxide. It has been found that (020) is the active facet of orthorhombic WO3·0.33H2O but not of hexagonal WO3. The orthorhombic WO3·0.33H2O exposing the largest amount of (020) facets shows the highest photocatalytic activity for the degradation of rhodamine B under visible light illumination, which is 4.1 times as high as that of the sample exposing the least amount of (020) facets. [ABSTRACT FROM AUTHOR]