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Basal plane dislocations (BPDs) are a key factor influencing the advancement of the 4H-SiC semiconductor. In this paper, the effects of shear forces on the nucleation and movement of BPDs are revealed by employing molecular dynamics simulations. The stress–strain curves of 4H-SiC subjected to different shear forces at different temperatures are obtained. It is found that the decrease in mechanical properties of 4H-SiC is mainly due to the occurrence of dislocation. This study also delves into the complexities of dislocation entanglement and slip, unraveling the impact on the mechanical properties of 4H-SiC. Moreover, the causes of dislocation within the crystal lattice were clarified from a microscopic atomic vantage point, shedding light on the intricate mechanisms involving chemical bond rupture and regeneration. These findings not only enrich our understanding of BPDs nucleation but also provide invaluable insights for mitigating BPDs in 4H-SiC. [ABSTRACT FROM AUTHOR]

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Transition metal as flame retardant has attracted intense interests in recent years. In this work, ZnO@MOF@PZS was prepared via hydrothermal and polycondensation methods. ZnO nanoflowers played the role as a template for growth of MOF@PZS and zinc source for formation of MOF. Subsequently, the obtained ZnO@MOF@PZS was mixed into polyurea (PUA) to investigate its flame retardancy and toxicity suppression properties. The cone calorimeter test (CCT) showed that ZnO@MOF@PZS significantly improved the flame retardancy of PUA composites. The addition of 3 wt% ZnO@MOF@PZS into PUA could result in peak heat release rate (PHRR), total heat release (THR) and total CO production (TCO) of 28.30%, 19.59% and 36.65%, respectively. The result of universal testing machine showed that ZnO@MOF@PZS‐add PUA had better mechanical properties. It is notable that the improved flame retardant properties for PUA composites are mainly attributed to ZnO@MOF@PZS promoting the formation of dense char residue. [ABSTRACT FROM AUTHOR]

Designing one-dimensional (1D) magnetic-carbon composites microwave absorbers is a promising strategy that can meet the current demand for high-performance microwave absorption (MA) materials. In this work, hierarchical structured Fe 3 O 4 /Fe@C@MoS 2 nanofibers were successfully obtained via a simple three-step method. 1D Fe 3 O 4 /Fe@C nanofibers were fabricated through electrospinning technology and in-situ polymerization followed by carbonization and reduction in H 2 /N 2 atmosphere. MoS 2 nanosheets grew irregularly on the surface of 1D Fe 3 O 4 /Fe@C nanofibers to form the flower-like structure. The morphology, composition and magnetism of samples were systematically investigated. Furthermore, electromagnetic characteristics and MA properties of Fe 3 O 4 /Fe@C nanofibers and Fe 3 O 4 /Fe@C@MoS 2 nanofibers were compared. The minimum reflection loss (RL min) of Fe 3 O 4 /Fe@C@MoS 2 nanofibers could reach −53.79 dB at 11.12 GHz and the corresponding absorption bandwidth (RL < -10 dB) of 4.4 GHz was achieved at the absorber thickness of 2.24 mm. This work combines electrospinning technology with traditional chemical synthesis to prepare a novel 1D core-shell microwave absorber, which provides some inspiration for preparing MA material in the future. [Display omitted] [ABSTRACT FROM AUTHOR]

Hierarchical structured ZnFe 2 O 4 @SiO 2 @C@NiO/reduced graphene oxide (ZSCN/RGO) composites were designed and fabricated via a multi-step route. One-dimensional (1D) ZnFe 2 O 4 @SiO 2 nanochains were fabricated through magnetic-field-induced stöber method. ZnFe 2 O 4 @SiO 2 @phenolic resin nanochains were synthesized through in-situ polymerization and then after high-temperature carbonization ZnFe 2 O 4 @SiO 2 @C (ZSC) nanochains were obtained. 1D ZSCN nanochains with flower-like surface were formed after NiO nanosheets grew irregularly on the surface. Finally, ZSCN/RGO composites with ZSCN nanochains anchoring on RGO nanosheets were successfully synthesized. The morphology, structure, composition and magnetic performance were systematically investigated. Moreover, the microwave absorption (MA) properties of ZSCN nanochains and ZSCN/RGO composites were compared. The results indicate that ZSCN/RGO composites exhibit a minimum reflection loss (RLmin) of −66.38 dB (9.58 GHz) and an effective absorption bandwidth (EAB) of 3.44 GHz (8.12–11.56 GHz) at a thickness of 2.45 mm, due to the synergetic effect between ZnFe 2 O 4 , SiO 2 , carbon, NiO and RGO. • One-dimensional ZnFe 2 O 4 @SiO 2 @C nanochains were synthesized successfully. • The flower-like structure was obtained after NiO nanosheets grew on ZnFe 2 O 4 @SiO 2 @C nanochains by the hydrothermal method. • The microwave absorption mechanism of ZnFe 2 O 4 @SiO 2 @C@NiO/reduced graphene oxide was demonstrated in depth. • The strongest absorption of -66.38 dB and the effective absorption bandwidth of 3.44 GHz can be obtained. [ABSTRACT FROM AUTHOR]

With the seriously environmental pollution, photocatalytic technology has been extensively studied for ensuring the continuous development of society. As a type of appealing semiconductor, bismuth-based materials have become a research hotspot in the field of photocatalysis due to their unique electronic structure, appropriate bandgap energy, high light quantum and outstanding electronic transmission efficiency. However, the separation and recovery of photocatalyst from reaction systems is difficult. The most promising strategy to facilitate separation process is to introduce a magnetic component. This review has mainly involved a classification, current challenges and prospects on the recent progress in fabrication of magnetic bismuth-based photocatalytic materials, as well as the list of their degrade object, dosage, initial concentration and reaction time. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) microwave absorbers have attracted wide attention in the field of microwave absorption (MA) because of the significant anisotropy and great dielectric attenuation of 1D architecture. In this work, the novel 1D flower-like yolk-shell Fe 3 O 4 @SiO 2 @NiO (FSN) nanochains have been fabricated through a modified Stöber and a simple hydrothermal method. The unique 1D flower-like yolk-shell architectures have large surfaces, multiple interfaces and void spaces. Benefitting from these advantages, the FSN nanochains showed excellent MA properties. Compared with the sample loaded with 10 wt% 1D flower-like yolk-shell FSN nanochains, the sample loaded with 30 wt% showed strong MA performance with a minimum reflection loss (RL) value of −54.28 dB (12.9 GHz) and an effective absorption bandwidth of 4.0 GHz (11.05–15.05 GHz) at the thickness of 2.54 mm. The 1D flower-like yolk-shell FSN nanochains with strong absorption, broad absorption bandwidth and thin layers, provided a new method for fabricating 1D MA materials and will become the promising candidates in the practical MA fields. • One-dimensional yolk-shell flower-like Fe 3 O 4 @SiO 2 @NiO nanochains were synthesized successfully. • The yolk-shell structure was obtained while the NiO nanosheets grew on Fe 3 O 4 @SiO 2 nanochains by the hydrothermal method. • The microwave absorption properties of Fe 3 O 4 @SiO 2 @NiO nanochains composites were elucidated in depth. • The strongest absorption of −54.28 dB and the effective absorption bandwidth of 4.0 GHz can be obtained. [ABSTRACT FROM AUTHOR]