The photoactive alpha-phase perovskite plays a pivotal role in determining the efficiency and stability of perovskite solar cells (PSCs). Herein, we propose an innovative strategy for seed-assisted epitaxial growth based on latticematching. The pre-synthesized (GABA)2PbI4 single crystals as seeds are introduced into the three-dimensional (3D) perovskite precursor solution, successfully achieved the preferential and rapid formation of the photoactive alpha-phase at room temperature. In situ grazing-incidence wide-angle X-ray scattering (GIWAXS) reveals the seed-induced accelerated crystallization process of the alpha-phase perovskite. The highly matched lattice constants between the seeds and alpha-FAPbI3, the reduced nucleation barrier, and the suppressed delta-phase are analyzed to be the primary factors, ultimately resulting in the formation of vertically oriented, gradient-distributed perovskite films. Finally, FACs-based perovskite devices fabricated by using this method achieved a high efficiency of 24.15% and excellent stability, retaining over 90% of their initial efficiency after 900 h.

Self-destructing microchips based on thermite reactions have emerged as an effective strategy for information security. However, conventional nanothermites suffer from unbalanced heat release, gas generation and pressure output, which severely restrict their destructive efficiency. Herein, we fabricated a three dimensionally ordered macroporous (3DOM) CuBi2O4/Al energetic composite via polymethyl methacrylate (PMMA) colloidal templating approach. Attributing to both the tunable pore sizes and distinct 3D structure of the CuBi2O4 framework, the interfacial contact and diffusion length between fuel and oxidant can be effectively regulated. As a result, among the investigated samples, the system with a pore size of 156 nm exhibits the highest heat release of 1610.84 J/g, together with a peak pressure of 266 kPa and a pressurization rate of 1315 MPa/s. The optimized performance originates from an optimized balance between fuel-oxidizer interfacial contact and oxygen transport at an appropriate length scale, enabling efficient reaction propagation and enhanced reaction completeness. The 3DOM framework promotes uniform fuel distribution and efficient interfacial interactions, thereby facilitating rapid energy release. Density functional theory calculations further reveal enhanced electron transfer at the interface, supporting the accelerated reaction kinetics. More importantly, the fabricated energetic microchip can achieve complete physical self-destruction within 4 ms. The favorable combustion performance of Al/3DOM-CuBi2O4 reveals the dependability of our proffered strategy for enhancing information security.

Aqueous Zn-ion batteries (AZIBs) hold great expectations in large-scale energy storage systems owing to the ascendance of remarkable safety, cost-effectiveness, and praiseworthy theoretical specific capacity. However, the deficient interfacial stability of the Zn anode, caused by uncontrollable dendrite growth and parasitic side reactions, hampers the practical applications of AZIBs. Herein, a zincophilic-hydrophobic surface with 3D fish-scale-like lamellar architecture was in situ fabricated on the Zn anode (LZ@Zn) via a lysine chemical etching and complexation process to resolve the above dilemmas. Attributing to both the zincophilic-hydrophobic properties and distinct 3D structure, the LZ@Zn anode can not only expel water molecules, but also accelerate Zn2+ de-solvation, lower the energy barrier for nucleation, and regulate the diffusion behavior of Zn2+. This enables it to suppress side reactions and achieve even Zn deposition, thereby ensuring the high stability of the Zn anode. Consequently, the LZ@Zn||Cu half-cell exhibits commendable reversibility with an average coulombic efficiency of 99.82 % over 1500 cycles. Moreover, LZ@Zn||LZ@Zn symmetric cell can achieve exceptional reversibility for cycling 6000 and 4000 h at 1 and 5 mA cm-2, respectively. The favorable electrochemical performance of the LZ@Zn reveals the dependability of this proffered strategy for achieving a stabilized and reversible Zn anode.

Niobium (Nb) is considered an excellent high-temperature structural material for aerospace applications. However, its poor oxidation resistance at temperatures above 600 degrees C limits its broader application. In this study, an NbSi2/YAG coating was prepared using the pack cementation and atmospheric plasma spraying (APS) methods to enhance the oxidation resistance of Nb substrate at high temperatures. Results indicated that the YAG top coating significantly prolonged the service life of the coating at high temperatures, achieving over 65 h at 1350 degrees C and over 20 h at 1500 degrees C. After 50 thermal shock cycles at 1500 degrees C, the coating systems remained wellbonded, with no evident spallation of the YAG coating, demonstrating excellent high-temperature thermal shock resistance. Microstructural analysis revealed that the YAG coating effectively inhibits the diffusion of oxygen, thereby suppressing the oxidation of the NbSi2 coating and the growth of the TGO layer. As the temperature increased and oxidation time extended, different regions of the NbSi2 layer exhibited varying degrees of oxidation. Once the deeply oxidized zone extends to the substrate, coating failure occurs. This study confirms that the preparation of an NbSi2/YAG coating is an effective approach to improve the oxidation resistance of Nb substrate.

The electrocatalytic degradation of tetracycline (TC) antibiotics remains challenging due to the limitations of conventional electrode materials, particularly the low electrochemical activity and short service life of Sb-doped SnO2 (SnO2-Sb) electrodes. To address these issues, this work introduces a synergistic strategy combining microdefect surface engineering with Sb-Nd co-doping, successfully fabricating a high-performance gradient-structured electrode. A TiO2-x interlayer rich in Ti3 + /oxygen vacancies and a micro-defect-engineered SnO2-Sb-Nd catalytic layer were sequentially constructed on titanium foam (Ti foam) via a sol-gel method. Systematic investigations were conducted to elucidate the influence of surface defect structure and doping synergy on electrode performance. Results demonstrate that at a Sn:Sb:Nd molar ratio of 10:3:0.75, the electrode achieves significantly enhanced electron mobility and maximized active site exposure through micro-defect and co-doping synergism. The optimized electrode exhibits an oxygen evolution potential of 2.04 V (vs. SCE), a low charge transfer resistance of 23.15 Omega center dot cm- 2, 98.62% removal of 20 mg center dot L- 1 TC within 20 min, and a service life extended to 4.18 times that of conventional electrodes (2.626 years). Mechanistic studies identify center dot O2- and 1O2 as the primary active species. This work provides a novel design strategy for overcoming the performance limitations of metal oxide electrodes through synergistic micro-defect and doping engineering.

Oxygen evolution reaction (OER) limits the efficiency of water electrolysis, and developing electrocatalysts that combine high activity with low cost is challenging. In this work, we prepare V-NiFe2O4@V-NiO/NF electrodes by a one-pot hydrothermal method. Vanadium doping introduces lattice strain and oxygen vacancies, which alters the electronic structure of the active sites, while the contact between NiFe2O4 and NiO phases improves charge transfer and exposes additional active sites. The optimized electrode reaches 10 mA center dot cm-2 at 198 mV overpotential and 100 mA center dot cm-2 at 241 mV of overpotential in alkaline solution. It also operates continuously for 100 h at 100 mA center dot cm-2 without evident performance loss. DFT calculations indicate that vanadium doping reduces the energy barrier for the rate-determining step and enables a lattice oxygen-mediated mechanism. These results demonstrate a viable approach to improving transition metal catalysts through vanadium doping and highlight design principles for durable, inexpensive OER electrodes.

Electrochemical (EC) oxidation is a promising technology for the degradation of emerging and persistent organic pollutants in water remediation. It is urgent priority to develop an electrode with high efficiency, long cycle life and high safety characteristics. In comparison to traditional titanium (Ti), three-dimensional porous substrates, such as Ti foam, is more beneficial for the rapid mass transfer. Herein, an engineering vacancies (Ovs) homojunction SnO2-x-Sb@SnO2 catalyst integrated with two crystallization levels (high-crystallinity and lowcrystallinity) is developed to enhance the degradation activity of organic pollutants. The Ar-assisted Ce doping-induced Ovs enhance the electrochemical performance and durability of the composite electrode by boosting interfacial electron transfer. Specifically, the Ti foam/SnO2-x-Sb@SnO2 with high concentration of OVS demonstrated an exceptionally rapid degradation rate of cephalexin (CFX) at 0.05490 min-1, facilitated by both radical attack mechanisms and direct electron-transfer (DET) processes. The novel anode demonstrated exceptional stability, with a predicted service life of 2.3 years. The theoretical calculations indicate the multiple contact interfaces present in the homojunction SnO2-x-Sb@SnO2 catalyst strengthen the interfacial internal electric field (IEF). This enhanced IEF significantly aids in facilitating charge separation and transfer at the interface, which is vital for improving electrochemical performance. This engineered interfacial design opens up new opportunities for the development of highly efficient and stable electrodes.

Developing efficient and environmentally benign heterogeneous catalysts that activate peroxymonosulfate (PMS) for the degradation of persistent organic contaminants remains a challenge. Metal-organic frameworks (MOFs)-derived metal oxide catalysts in advanced oxidation processes (AOPs) have received considerable attention research fraternity. Herein, we report an innovative magnetic trimetallic MOF-derived Fe-Mn-Sn oxide heterostructure (FeMnO@Sn) with adjustable morphology, size and Sn content, prepared through an impregnation-calcination strategy. The formation of a novel magnetic Fe2O3/Fe3O4/Mn3O4 heterostructure induces the generation of abundant Fe2+ and Mn2+ sites on the FeMnO@Sn surface. Meanwhile, the introduction of SnO2 into the Fe2O3/Fe3O4/Mn3O4 heterostructure facilitates the cleavage of the OO bond in adsorbed PMS. The synergy among the different functionalities of each metal oxide plays a vital role in the swift and effective degradation of pollutants. In addition, the uniquely designed catalyst exhibits magnetic properties that facilitate easy recycling and repeated use, thereby meeting environmental protection requirements. Overall, this research highlights the design of heterogeneous catalysts for the effective activation of PMS and provides valuable insights for the advancement of future environmental catalysts.

Microcapsules of polystyrene (PS) containing polyether amine (PEA) were prepared by solvent evaporation method. The effects of varying core-to-shell ratio, agitation rate, emulsifier type and ratio on the preparation of microcapsules were investigated. The physical and chemical properties of microcapsules were comprehensively characterized by optical microscope, scanning electron microscope, Fourier infrared spectroscopy and thermogravimetric analysis. The results demonstrate that microcapsules prepared with a core-to-shell ratio of 2:1, agitation rate of 400 r/min and an emulsifier consisting of 1 wt

The fabrication of Sb-doped SnO 2 electrode with high catalytic activity and excellent durability for decomposition PPCPs (Pharmaceuticals and personal care products, PPCPs) is challenging. Herein, a Ti 3 + /O vs -related TiO 2_x is prepared by short -time annealing at low temperature in mixed gas with Zr as a cocatalyst. DFT calculations indicate that the introduction of Ti 3 + /O vs defects could promote the formation of more center dot OH. Then, the nanoflower rod -like SnO 2 -Sb catalytic layer supported on dual -defects TiO 2_x is successfully synthesized by onestep pulse electrodeposition (PLED) combined with hydrothermal methods (H). This newly pulse electrodeposition technique solves the short lifetime problem of SnO 2 -Sb nanoflower electrodes current hydrothermal-based methods. 1 O 2 and center dot OH are found to be the primary reactive oxygen species (ROSs) by radical quenching tests and electron paramagnetic resonance analysis. The optimized Ti foam/TiO 2_x /SnO 2 -Sb electrode could degrade over 96.3 % of 20 mg L _ 1 amoxicillin (AMX) within 30 min, corresponding kinetic constant 0.10228 min _ 1 . This will provide inspiration for the construction of defect engineering and new insights for the development of low-cost and high electrooxidation activity Sb-doped SnO 2 electrode.

Phenolic resin was coated on the surface of nano-Si by a microencapsulation technique, and then carbonized under Ar protection to prepare a nano-Si/C composite. The composites were first prepared using 4 different mass ratios (1:2, 1:4, 1:6, 1:8) of phenolic resin to nano-Si. The obtained average thicknesses of amorphous carbon coating were 7, 4.5, 3.7, 2.8 nm, respectively. By comparing the cycling and rate capability, the best electrochemical performance was obtained when this ratio was 1:4, with a 4.5 nm amorphous carbon coating. The electrochemical properties of this material were then comprehensively evaluated, showing excellent electrochemical performance as an anode material for Li-ion batteries. At a current density of 100 mAg−1, the material had a first specific discharge capacity of 2 382 mAhg−1, a first charge specific capacity of 1667 mAhg−1, and an initial coulombic efficiency of 70%. A discharge specific capacity of 835.6 mAhg−1 was retained after 200 cycles with a high coulombic efficiency of 99.2%. In addition, the nano-Si/C composite demonstrated superior rate performance. Under current densities of 100, 200, 500, 1 000 and 2 000 mAg−1, the average specific discharge capacities were 1 716.4, 1 231.6, 911.7, 676.1 and 339.8 mAh g−1, respectively. When the current density returned to 100 mA g−1, the specific capacity returned to 1 326.4 mAh g−1.

In this study, graphene oxide (GO) was employed as nanoscale reinforcement for the development of high-performance carbon fiber reinforced plastic (CFRP) composites. Initially, epoxy resin was modified by incorporating GO with different weight proportion from 0.05 to 0.6 wt.%. Then the unidirectional CFRP composites were prepared with the modified epoxy resin by winding and compression molding technique. The optimized GO-CFRP composites with GO content of 0.1 wt.% present tensile strength of 2756 MPa and monofilament interfacial shear strength of 29.06 MPa, respectively, which are 14.4% and 12.5% higher than the corresponding values of the pristine CFRP composites. To intuitively observe the fracture process of the CFRP composites, the digital image correlation system was employed. It is verified that the moderate addition of GO can improve the stress concentration of the CFRP composites during the deformation process. In addition, the reinforcing mechanism is investigated by analyzing the fracture surface of the modified epoxy resin and the CFRP composites. The results indicate that GO can make the cracks deflect or bifurcate along with the epoxy resin which closes to graphene, resulting in synergistically improved mechanical and interfacial properties of the GO-modified CFRP composites.

小角X射线散射技术(SAXS)是研究碳材料内部微孔结构的重要方法之一.当X射线照射到样品上时,如试样内部存在任何纳米尺度的密度不均匀区,在入射X射线束周围小角度范围内均会出现不同程度的X射线散射现象.基于此,利用SAXS不仅可以获得碳材料的孔结构信息,更微观的微电子密度起伏和较大尺度的微原纤结构信息都可以通过适当的方法解析出来.近年来,针对碳纤维等碳结构的SAXS解析理论逐渐深入,包括Debye相关距离理论等经典理论纷纷出现新的应用尝试,而Unified fit模型、"Ruland streak"法等的出现也使研究者对碳结构有了更新和更全面的理解.首先,准两相体系下碳纤维微观结构的SAXS分析取得突破.以De-bye相关距离理论为突破口对碳纤维散射体系类型进行分析时发现,碳纤维与其石墨化纤维在微观和介观尺度上存在显著差异性,其差异性的根源在于碳的无定型结构状态,且此类结构的散射信息可以被SAXS所捕捉,进而成为总散射强度的分量.此时,利用Unified fit模型或"双Debye"模型可以很好地分析准两相体系中无定形结构和微孔的结构特征.其次,基于"Ruland streak"法的散射体取向分析方法被成功应用于碳纤维孔结构分析.该方法假设了择优取向的散射体具有较大的长径比,而散射强度主要集中于散射体主轴的法向,单个散射体将产生一个沿法向的散射条纹,因此散射体的取向可以通过分析接收器平面内散射体法向散射信号的分布而得到.此外,将Porod理论应用于碳结构内部微电子密度起伏分析和将麦克斯韦函数应用于碳纤维孔结构分布分析也是近年来涌现的新理论、新技术.据此本文综述了近年来应用SAXS对碳纤维进行微观结构表征的进展,对SAXS应用于碳材料微电子密度起伏、分形结构、孔隙结构、择优取向、无定形结构的测试及数据解析进行了详细阐述.

Healing agent microcapsules have been used to realize self-healing for polymeric composites. In this work a novel kind of microcapsules encapsulating ethylenediamine (EDA) with epoxy resin as shell material were prepared by interfacial polymerization technology. The oil phase was epoxy resin prepolymer and carbon tetrachloride, and the water phase was EDA and deionized water. Under the action of emulsifier, a stable water-in-oil emulsion was formed. Then the emulsion was added to dimethyl silicone oil, stirred and dispersed, to prepare microcapsules. In addition, the factors affecting the preparation of microcapsules were studied. In this study, Fourier transform infrared(FTIR) was carried out to demonstrate the chemical structure of ethylenediamine microcapsules. Optical microscope(OM) and scanning electron microscope(SEM) were used to observe the morphology of microcapsules. Thermogravimetric analysis and differential scanning calorimetry were done to investigate the thermal properties of microcapsules. Permeability experiment and isothermal aging test were executed to verify the environment resistance of microcapsules. Results showed that EDA was successfully coated in epoxy resin and the microcapsule size was in the range of 50~630 μm. The synthesized microcapsules were thermally stable below 75 °C and perfect permeability resistance to ethanol solvent.

介绍了电泳沉积的基本原理,纳米粒子悬浮液的分散机制,并详细讨论了电泳沉积碳纳米管、氧化石墨烯、二氧化硅、纳米纤维等纳米粒子在碳纤维增强树脂基复合材料界面改性方面的研究进展.

通过模拟环境因素对碳纤维增强树脂基复合材料(CFRP)板的耐候性及湿热老化性能进行了检验,研究了CFRP板的抗拉强度、弹性模量及断裂伸长率随严苛环境下的暴露时间的变化规律.研究表明强紫外线、湿冷环境和酸碱侵蚀对CFRP板性能影响较大,90天周期内拉伸强度下降了10％ 左右,拉伸模量下降15％ 左右;纯水、盐溶液及加速湿热老化的影响则并不十分显著.扫描电镜观察发现,绝大多数侵蚀性破坏首先发生在树脂层,提高基体树脂的性能将有助于增强CFRP的耐久性.

Three dimensionally ordered macroporous (3DOM) Ce-based catalysts were successfully prepared via a surfactant-assisted colloidal crystal template (CCT) route. The as-synthesized catalysts showed well-ordered structures with macropores and small interconnected pore windows. The Raman results indicate that the catalyst persists pure fluorite cubic phases until the molar ratio of Mn exceeds 0.3, therefore MnOx particles form and impede the contact of the active site and the reagent and restraining soot combustion. The doping of Nd into MnOx-CeO2 enhances the catalytic activity because of increased oxygen vacancy, Mn4+ content and stronger redox ability. Nd-doping also improves thermal stability of the catalyst due to less sintering and none phase separation after thermal aging. The fresh and aged Mn0.3Ce0.6Nd0.1O2 catalysts show the maximum oxidation rate for soot at 331 and 355 degrees C in the O-2/N-2 atmosphere, achieving a nearly 100% CO2 selectivity. (C) 2018 Published by Elsevier B.V. on behalf of Chinese Society of Rare Earths.

The relationship between mechanical properties and micro-structures of carbon fibers was reconsidered based on the "elastic unwrinkling" model and Griffith microcracks theory. Experimental results showed, stress relaxation and elastic unwrinkling process could both be observed in non-graphitic fibers, the tensile deformation of which was suitable to be described by "elastic unwrinkling" model. However, elastic unwrinkling process was not so obvious in graphitic fibers since the recrystallization of the crystalline structure had changed the shear compliance of the carbon lattice. A correction towards the compliance was proposed in this case based on the surface fractal of the graphitic fibers. On the other hand, the relationship between tensile strength and the void's parameter of carbon fibers was found generally follow the Griffith equation. In addition, some factors besides of voids, e.g., the local density fluctuation etc., were also found indirectly related to the tensile fracture process of carbon fibers, while a complete exposition of the influencing mechanism remained to be further explored.

A method of high temperature CWPO with a combination pretreatment process of acidification demulsion, extraction and steamed ammonia whose effluent presented its temperature as high as 87 to 95 ℃ was investigated to improve the biodegradability of coal gasification wastewater.Compared 3％ Fe/Al2O3 and 3％ Fe/SAC,over 60％ of COD and 90％ of the total phenol could be removed under the optimized condition(temperature of80 ℃ , pH0 of4,H2O2 of 7.8 to 10.5 mg · L-1, LHSV of 0.5 h-1) with 3％ Fe/SAC for the pretreatment of coal gasification effluent.COD removal rate as high as 60％ , the total phenol removal rate as high as 90％above, the H2O2 utilization rate was more than 99％ and chromaticity by initial 1 000 times down to 2 times, in addition, the effluent could reach the requirements of water quality standard for biochemical treatment system due to its high biodegradability as B/C =0.51.

采用熔盐法,以NaCl-KC1作熔盐介质,利用Si粉与碳纤维反应在纤维表面制备出均匀的SiC涂层.研究了反应温度、热处理时间和Si/C比对SiC涂层结构和形貌的影响.研究结果表明:随着热处理温度、热处理时间以及Si/C比的增加,纤维表面涂层厚度与SiC晶粒尺寸增加,但是涂层厚度增加随着Si/C比的增加变化较小.与未涂层碳纤维相比,SiC涂层明显改善了碳纤维的抗氧化性能.1350℃热处理3h制备的SiC涂层致密均匀,其起始氧化温度由540℃增加至650℃.