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Flue gas desulfurization facilities produce flue gas desulfurization ash (FGDA), which has ecological and economic benefits. In this article, we explored the possibility and impact of using FGDA as the sole reinforcing filler to mechanically improve epoxidized natural rubber (ENR). The influence on the properties of the composites was examined. FGDA exhibits good interfacial interaction and compatibility with ENR, which improves the mechanical properties of ENR. When 15 phr FGDA was added, the tensile strength of the composites increased by approximately 41.4% compared with that of pure ENR. This work demonstrates the possibility of using FGDA as an effective and sole reinforcing material to enhance the properties of rubber materials. Highlights * FGDA improves the mechanical properties of ENR as a sole reinforcing filler. * FGDA reacts with ENR during vulcanization, enhancing compatibility. * Adding 15 phr FGDA to ENR increases the tensile strength by 41.4%. KEYWORDS composites, mechanical properties, rubber, vulcanization, 1 | INTRODUCTION Flue gas desulfurization ash (FGDA) is a substance created during the semidry desulfurization process, which involves using Ca[(OH).sub.2] to react with S[O.sub.2] generated from fossil fuel combustion [...]

The rapid advances in photochromic devices have spurred great enthusiasm in the design and preparation of luminescent materials. It is an efficient and facile strategy to incorporate ZnS-based phosphors into crosslinking polymer substrates, obtaining photochromic materials with excellent comprehensive properties. However, crosslinking polymeric ZnS-based phosphor luminous materials are unable to be recycled and reprocess at the end of service, limiting their long-term utilization and burdening the environment. Besides, few reported works have explored photoluminescent properties of samples during multiple reprocessing and recycling. Herein, enlightened by the intriguing dynamic covalent crosslinking technology, recyclable and photoluminescent elastomers, employed polymeric flexible matrixes with dynamic covalent joints integrated with ZnS:Cu and ZnS:Cu,[M.sub.n] phosphors, were prepared in this work. Due to the breakage and reformation of exchangeable crosslinking connections and intensive interfacial interactions between polar elastomeric matrixes and luminophores, the original and recycled composites exhibit excellent recyclable, photoluminescent, and mechanical properties. We anticipate that the strategy of this work, inserted phosphors into dynamic crosslinking polymer matrixes with a facile fabrication process, paves the way for the recycling and long-term utilization of photoluminescent materials. KEYWORDS composites, elastomers, luminescence, recycling, 1 | INTRODUCTION Luminescent materials, under proper external stimuli, exhibit photoluminescent, electroluminescent, and mechano-luminescent properties, [1-6] extensively applied in display, sensing, anticounterfeiting, bioimaging, and biological probes. [7-11] Three types of [...]

Antiferroelectric (AFE) Pb0.96La0.04Zr0.90Ti0.10O3 (PLZT) and AgNbO3 (AN) ceramics were fabricated codoped with 1 mol% Er and various contents of Yb3+ ions. The ceramics exhibit good energy storage performances and electric‐field‐controlled photoluminescence (E‐PL) intensity modulations, both of which are attributed to the reversible AFE‐ferroelectric phase transition that accompanies a structural evolution. Accordingly, a noncontact energy charge/discharge monitor is proposed based on the E‐PL effect, which is convenient and safe for the high‐energy density capacitors. Besides, the PLZT and AN ceramics exhibit opposite E‐PL behaviors that are caused due to different crystal space group transitions. [ABSTRACT FROM AUTHOR]

Compared with powder particles, ceramic block piezocatalyst possesses the advantages of high cycle stability, decreasing secondary pollution, and easy recovery. Herein, with a simple strategy of the poling procedure, the piezocatalytic activity of 0.96K0.5Na0.5NbO3‐0.04Bi0.5Na0.5ZrO3 (abbreviated as 0.96KNN‐0.04BNZ) ceramic blocks can be considerably improved. A reaction rate constant k value of 14.70×10−3 min−1 in the poled sample can be obtained to degrade Rhodamine B, which is 3.44 times that of the unpoled one. Meanwhile, the poled sample also has good degradation effects against methylene blue and amino black 10B. The improvement of piezocatalytic activities originates from the reduction of crystal symmetry and the enhancement of electron‐hole pair separation, which accelerates the generation of charge carriers. This research displays a unique lead‐free bulk piezocatalyst and a convenient method for enhancing its piezocatalytic activity. [ABSTRACT FROM AUTHOR]

In this work, the frequency dependence of ferroelectric and electrocaloric properties in barium titanate-based ceramics was studied based on Maxwell relations. It is found that the maximum and remnant polarization will decrease while the coercive field increases a lot with rising frequency from 0.1 to 10 Hz, indicating that polarization rotation and domain switching become difficult at high frequencies. The electrocaloric properties show the different frequency dependence at different phase structures. Isothermal entropy change (Δ S) and adiabatic temperature change (Δ T) are similar around/above Curie temperature ( T C) , showing tiny frequency dependence. However, Δ S and Δ T display the obvious frequency dependence below T C , especially in the orthorhombic–tetragonal phase-transition region with a stable ferroelectric phase, and this frequency dependence becomes more obvious under a low-electric field. It is also found that increasing the frequency can weaken the electric field dependence of electrocaloric strength. This work gives a general profile of frequency dependence for electrocaloric properties in ferroelectric ceramics. [ABSTRACT FROM AUTHOR]

The phase transition temperature (e.g., that of orthorhombic‐tetragonal TO‐T) of relaxor ferroelectrics are commonly obtained through electrical method (i.e., temperature dependence of dielectric constant), and the samples need to be coated with metal electrode and tested by a sophisticated impedance analyzer. This contact measuring method is inefficient, inconvenient and easy to damage the sample surface, inapplicable to transparent ferroelectrics. Here, we successfully fabricated Bi/Sm co‐doped K0.5Na0.5NbO3 transparent ceramics with photoluminescent behavior and relaxor‐like ferroelectricity, which simultaneously realized TO‐T monitoring and temperature sensing via fluorescence intensity ratio (FIR) technology. This simple, rapid, noncontact and nondestructive optical way displays small TO‐T deviation (merely 0.78%) compared to the electrical method. And the temperature‐dependent optical characteristics and coercive electric field all present abrupt changes, whose abnormal temperature regions are in accordance with that around TO‐T. In addition, the maximum absolute sensitivity and relative sensitivity of the ceramics reach 0.0072 K−1 (at 533 K) and 0.0111 K−1 (at 453 K), respectively, exhibiting superior optical temperature sensing performance. The tactical use of FIR technology is of great significance for widening the applications of luminescent‐ferroelectric transparent ceramics. [ABSTRACT FROM AUTHOR]

In the biomedical field, polyvinyl alcohol (PVA) sponge has been widely used. In particular, it is considered a potential implant material for repairing soft tissues. However, its insufficient water absorption and mechanical properties limit its application. In this work, a novel PVA/halloysite nanotubes (HNTs)/gelatin ternary composite sponge was prepared by water solution mixing and casting techniques. HNTs and gelatin/PVA solution were mixed at different weight ratios. The structure of the ternary composite sponges was characterized by using scanning electron microscopy. The physical properties of the ternary composite sponges were characterized. The maximum water absorption reached 1783.5% with a rapid water absorption speed at a weight ratio of HNTs/gelatin of 1:8. Owing to its interconnected macroporous structure and good interfacial interaction, its highest compression strength and tensile strength reached 8.22, 1.51 MPa, respectively. In addition, its thermal stability was enhanced as well, which demonstrated that the prepared composite sponge had better performance than the pure PVA sponge by constructing a ternary system. Therefore, the results suggest that the PVA/HNTs/gelatin ternary composite sponge shows a wider application value as a potential material for repairing soft tissue. Highlights: A composite PVA sponge with promising applications in tissue engineering.Simple preparation method, water solution mixing and casting techniques.Pioneering a PVA/HNTs/gelatin ternary system sponge.Improved water absorption ability and mechanical properties. [ABSTRACT FROM AUTHOR]

Traditional solid‐state luminescent materials (e.g., phosphors and microcrystalline glasses) have attracted extensive attention due to their high energy efficiency and long lifespan. However, their application scope is limited by complex compositions and manufacturing processes, as well as single‐function. In this study, solid‐state reaction was utilized to prepare transparent‐ferroelectric (K0.5Na0.5)NbO3 (KNN) ceramics by simply codoping with Dy3+ and Sr2+, providing possibilities for large‐scale production. Ceramics exhibit high optical transmittance, high‐quality white‐light emission and relaxor ferroelectric feature. Under irradiation of UV light, photochromic behavior occurring in the ceramics, resulting in modulating the optical performances, especially quality of emitted white light. Multifunctionality can expand latent applications of KNN‐based ceramics from white light‐emitting diodes to modulated optoelectronic devices. [ABSTRACT FROM AUTHOR]