查找使用阿拉丁产品的科研文献

Reduced graphene oxide wrapped Na3(VO)2(PO4)2F microcubes for high-performance sodium-ion batteries

Wen Yu,Weizhou Chai,Zhenhua Chen,Haitao Li,Yu Qiao,Hangcheng Yang,Guiyin Xu,Hengda Sun,Yu Chen,Hongkang Wang

Na 3 (VO) 2 (PO 4 ) 2 F (NVOPF) has been recognized as a promising cathode of sodium-ion batteries (SIBs) owing to its high working potential and high energy density, but its practical application is hindered by the poor electronic conductivity and difficulty in structure regulation. Herein, we adopt the phytic acid (PA) as a new phosphorus source to chelate VO 2+ and Na + /F − ions under hydrothermal condition, leading to the successful fabrication of cuboid-like NVOPF with average length of 1.96 μm, while introduction of citric acid (CA) results in the formation of truncated cube-like NVOPF with uniform and smaller average length of 0.81 μm, which exhibits enhanced reaction kinetics and superior sodium storage performance. To overcome the poor conductivity of NVOPF, reduced graphene oxide (rGO) nanosheets are introduced during hydrothermal synthesis, leading to the formation of rGO-wrapped NVOPF microcubes (NVOPF/rGO) with tunable rGO contents. The optimized NVOPF/rGO demonstrates significantly improved electronic conductivity and excellent sodium storage performance, displaying a theoretically high reversible capacity of 130.3 mAh g −1 at 0.2C and outstanding cycling stability with a capacity retention of 100.0 mAh g −1 after 3500 cycles at 10C (corresponding a decay rate of 0.0043% per cycle). Operando synchrotron analysis reveals that Na 3 (VO) 2 (PO 4 ) 2 F undergoes complete solid solution reaction with V 4+ /V 5+ redox couples upon sodiation/desodiation, and the Na 3 (VO) 2 (PO 4 ) 2 F displays highly reversible lattice parameters with a small overall volume change of 2.28%, which almost completely recovers with a negligibly variation of 0.038%, indicating the robust structure stability of NVOPF. Moreover, the full cell with NVOPF/rGO cathode and hard carbon anode also demonstrates superior cycling stability for practical application.

Correction: α-Glycerol monolaurate promotes tight junction proteins expression through PKC/MAPK/ATF-2 signaling pathway

Siyu Dai,Cunjie Li,Dagang Li,Hong Wang

Nickel(II) cluster-based mixed-cation coordination polymer synthesized from 2-mercapto­benzoic acid and its application

Zhu J.,Yan S.,Xiao H.,Jiang J.,Li X.

High-nuclearity metal clusters have received considerable attention not only because of their diverse architectures and topologies, but also because of their potential applications as functional materials in many fields. To explore new types of clusters and their potential applications, a new nickel(II) cluster-based mixed-cation coordination polymer, namely poly[hexa­kis­[μ4-(2-carboxyl­atophen­yl)sulfanido]di-μ3-chlorido-tri-μ2-hydroxido-octa­nickel(II)sodium(I)], [Ni8NaCl2(OH)3(C7H4O2S)6]n, 1, was synthesized using nickel chloride hexa­hydrate and mercapto­benzoic acid (H2mba) as starting reactants under hydro­thermal conditions. The material was characterized by single-crystal X-ray diffraction (SCXRD), Fourier transform IR spectroscopy, thermogravimetric analysis, powder X-ray diffraction and X-ray photoelectron spectroscopy analysis. SCXRD shows that 1 consists of a hexa­nuclear nickel(II) [Ni6] cluster, dinuclear NiII nodes and a mononuclear NaI node, resulting in the formation of a complex covalent three-dimensional network. In addition, a tightly packed NiO/C&S nanocomposite is fabricated by sinter­ing the coordination precursor at 400 °C. The uniform nanocomposite consists of NiO nanoparticles, incompletely carbonized carbon and incompletely vulcanized sulfur. When used as a supercapacitor electrode, the synthesized composite shows an extra-long cycling stability (>5000 cycles) during the charge/discharge process.

Insight into {10 1‾ 2} twinning-driven high ductility behaviors in severely deformed titanium alloy composites

Xiaoqi Mao,Qichao Wei

The conventional approach of enhancing the strength of titanium alloys and their composites through mechanical processing to induce dislocations often leads to compromised ductility. In recent years, structural design strategies have stimulated the exploration of the material community towards deformation mechanisms and their impact on mechanical properties. Herein, we introduce the {10 1 ‾ 2} twinning to the B@Gr/TC4 composites, which were synthesized using ball milling, spark plasma sintering, hot rolling, and heat treatment processes. These composites are reinforced by in-situ formed TiC and TiB hybrid phases, achieving a high ultimate tensile strength (UTS) of 1424 MPa and fractured elongation (FE) of 13%, which are superior to those of TC4 alloy (with its UTS of 984 MPa and FE of 12%) and Gr/TC4 composite (with its UTS of 1325 MPa and FE of 12%). The enhanced strength of the composite is primarily attributed to the grain refinement and dislocation strengthening effects contributed by the high percentage of small-angle grain boundaries pinned by TiC and TiB hybrid phases. Furthermore, the twinning-induced strain softening effect is identified as the key mechanism for maintaining exceptional ductility. This study provides an effective structural strategy to simultaneously improve the strength-ductility of Ti matrix composites.

Stabilization of an Electric-Field-Induced Microscale (2 µm) Perovskite Light-Emitting Diode via Defect Engineering

He Huang,Yong Huang,Yang Ma,Qiangwei Wang,Yu Chen,Jiajun Qin,Jinpeng Li,Hui Yan,Xiaoqing Chen,Zilong Zheng

The miniaturization of perovskite light-emitting diodes (PeLEDs) to single-pixel dimension below 10 µm represents a critical challenge for next-generation high-definition displays. Conventional photolithography techniques face fundamental compatibility issues with perovskite materials, while the stability and efficiency of microscale devices are compromised by defect-mediated non-radiative recombination and ion migration effects at reduced dimensions. This work demonstrates a significant advancement in microscale PeLED performance through synergistic optimization of precursor stoichiometry and surface passivation engineering. By employing guanidinium bromide (GABr) as a multifunctional passivator, we achieved simultaneous bulk and surface defect suppression with the formation of a stabilizing 2D/3D heterostructure. The optimized 2 µm PeLED devices exhibited remarkable performance enhancements, achieving a peak external quantum efficiency of 7.4%, current efficiency of 42.3 cd/A, and luminance of 4.6 × 10 4 cd/m 2 . More importantly, the operational service lifetime was extended two orders of magnitude from 3 to 271 s, addressing the fundamental stability limitations that have previously hindered practical applications. This work provides an alternative fabrication pathway that circumvents the size constraints of conventional microfabrication processes, enabling the development of high-performance microscale light-emitting devices for augmented reality, virtual reality, and other advanced display technologies that require ultrahigh pixel densities.

Propofol Attenuates Hypoxia/Reoxygenation-Induced Apoptosis and Autophagy in HK-2 Cells by Inhibiting JNK Activation

Huaxin Wang,Xuan Peng,Yayi Huang,Yeda Xiao,Zhuo Wang,Liying Zhan

Purpose The aim of this study was to investigate whether propofol could attenuate hypoxia/reoxygenation-induced apoptosis and autophagy in human renal proximal tubular cells (HK-2) by inhibiting JNK activation. Materials and methods HK-2 cells were treated with or without propofol or JNK inhibitor SP600125 for 1 hour and then subjected to 15 hours of hypoxia and 2 hours of reoxygenation (H/R). Cell viability and LDH release were measured with commercial kits. Cell apoptosis was evaluated by flow cytometry. The expressions of p-JNK, cleaved-caspase-3, Bcl-2, and autophagy markers LC3 and p62 were measured by Western blot or immunofluorescence. Results HK-2 cells exposed to H/R insult showed higher cell injury (detected by increased LDH release and decreased cell viability), increased cell apoptosis index and expression of cleaved-caspase-3, a decrease in the expression of Bcl-2 accompanied by increased expression of p-JNK and LC3II, and a decrease in expression of p62. All of these alterations were attenuated by propofol treatment. Similar effects were provoked upon treatment with the JNK inhibitor SP600125. Moreover, the protective effects were more obvious with the combination of propofol and SP600125. Conclusion These results suggest that propofol could attenuate hypoxia/reoxygenation induced apoptosis and autophagy in HK-2 cells, probably through inhibiting JNK activation.

Solution-based synthesis of dense, large grained CuIn(S, Se)2 thin films using elemental precursor

Zhongdong Zhao,Yihan Qi,Qiuying Chen,Xuerong Zheng,Qiuyan Hao,Wen Zhang,Jing Mao,Caichi Liu,Hui Liu

Compared with the expensive and complicated vacuum techniques, the solution-based process to deposit I-III-VI 2 chalcogenide thin films (I=Cu, III=In or Ga, VI=S or Se) has attracted great interests due to its lower cost, higher scalable production and better application in flexible substrate . Herein, a low-toxic and high-active mixture solvent comprised of 1, 2-ethanedithiol and 1,2-ethylenediamine is utilized to dissolve elemental Cu, In and S powders at 60   °C, forming the CuInS 2 (CIS) precursor solution . After spin coating and annealing in a both Ar gas and selenium atmosphere, a dense and large-grained chalcopyrite CuIn(S,Se) 2 (CISSe) thin films with a close-packed grain size of ~800   nm are prepared, eliminating a undesired fine fine-grained bottom layer. In addition, the selenization temperature of the CISSe thin films is also discussed, which influences the phase composition, crystallinity and morphology of CISSe thin films. Photovoltaic device of the CISSe-based thin films is fabricated, obtaining a power conversion efficiency of 6.2% with an active cell area of 0.5   cm 2 under AM 1.5 illumination.

Preparation of planar CH3NH3PbI3 thin films with controlled size using 1-ethyl-2-pyrrolidone as solvent

Qiuyan Hao,Yixia Chu,Xuerong Zheng,Zhenya Liu,Liming Liang,Jiakun Qi,Xin Zhang,Gang Liu,Hui Liu,Hongjian Chen,Caichi Liu

Recently, planar perovskite solar cells based on CH 3 NH 3 PbI 3 have attracted many researcher's interest due to their unique advantages such as simple cell architecture, easy fabrication and potential multijunction construction comparing to the initial mesoporous structure. However, the preparation of planar perovskite films with high quality is still in challenge. In this paper, we developed a vapor-assisted solution process using a novel and green solvent of 1-Ethyl-2-pyrrolidone (NEP) instead of the traditional N, N-dimethylformamide (DMF) to construct a high-quality perovskite CH 3 NH 3 PbI 3 thin film with pure phase, high compactness, small surface roughness and controlled size. The phase evolution and growth mechanism of the perovskite films are also discussed. Utilizing the NEP of low volatility and moderate boiling point as solvent, we dried the PbI 2 -NEP precursor films at different temperature under vacuum and then obtained PbI 2 thin films with different crystalline degree from amorphous to highly crystalline. The perovskite films with crystal size ranged from hundreds of nanometers to several micrometers can be prepared by reacting the PbI 2 films of different crystalline degree with CH 3 NH 3 I vapor. Moreover, planar-structured solar cells combining the perovskite film with TiO 2 and spiro-OMeTAD as the electron and holes transporting layer achieves a power conversion efficiency of 10.2%.

Dual-functional C-composited Na3.16Fe2.42(P2O7)2 cathode toward superior electrochemical performance for sodium-ion batteries

Shiyu Li,Suhua Chen,Caiyan Yu,Huiling Zhao,Yanfeng Yin,Xiaosheng Song,Ying Bai,Lijun Gao

The development of a polyanion cathode for sodium-ion batteries is expected to accelerate the application of sodium-ion batteries in large-scale energy storage systems . However, the poor electrode conductivity is still a great challenge. In this paper, the novel carbon composite polyanion compound Na 3.16 Fe 2.42 (P 2 O 7 ) 2 @C (NFP@C) is developed through high-energy ball milling followed by annealing. The porous NFP nanoparticles modified with dual-functional C-composited for amorphous carbon coating and carbon nanofibers interpenetrating deliver excellent capacity retention of 85.3% after 1000 cycles at 5 C, which is more outstanding than pure NFP. X-ray diffraction, in situ galvanostatic intermittent titration techniques, electrochemical impedance spectroscopy , and cyclic voltammetry were performed to investigate the stability and sodium diffusion of NFP@C. The results show that the systematic and comprehensive dual-functional conductive network modification enables NFP exhibit excellent electronic and ionic conductivities , thereby improving the rate capability and cycling stability. Furthermore, a soft package sodium-ion full battery assembled based on NFP@C reveals a high-capacity retention of 95.2% for 150 cycles at 0.5C. This carbon composite strategy is simple and efficient and could be easily and widely extended to other cathodes in grid-scale energy storage applications .

Realizing 303 ps Ultrafast Scintillation Time in 2-Inch CsPbCl3 Single Crystals Grown Under Br2 Overpressure

Jingwei Yang,Fangbao Wang,Liang Chen,Tao Bo,Zhifang Chai,Wenwen Lin

Large-sized, room-temperature ultrafast scintillator single crystals are highly demanded for fast timing applications such as time of flight–positron emission tomography, high-speed medical imaging, and pulse heavy-ray detection. Sub-nanosecond scintillation was discovered in 16 mm sized CsPbCl3Brxsingle crystals in our previous research. In this work, the crystal size of CsPbCl3Br0.03was enlarged to 2 inches (50.8 mm). Meanwhile, by precisely optimizing the vertical Bridgman growth process, we further increased the concentration of Br dopant to realize even faster scintillation decay. In this study, we conducted a series of tests on the grown crystals, including temperature-dependent photoluminescence tests, alpha particle excitation tests, X-ray imaging tests, etc. Via the strategy of the incorporation of Br2, Br dopant introduces highly efficient fast recombination centers in perovskite CsPbCl3Br0.03crystals, resulting in an unprecedently fast scintillation decay time of 303 ps under241Amα-particle excitation, which is significantly shorter than that of the pure CsPbCl3and all other perovskites by at least two orders of magnitude. Benefiting from the excellent optical transparency and high crystalline quality of the CsPbCl3Br0.03crystal, an X-ray spatial resolution of up to 20 lp/mm is achieved. These results further demonstrate the great potential of large-sized CsPbCl3Brxsingle crystals for fast timing applications.

Influence of the PBI structure on PBI/CsH5(PO4)2 membrane performance for HT-PEMFC application

Yutong Zhao,Bo Lv,Wei Song,Jinkai Hao,Junfang Zhang,Zhigang Shao

Conventional high-temperature proton exchange membranes use phosphoric acid (PA) as a proton conductor . However, PA loss, poor mechanical stability, and catalyst poisoning represent major limitations. Solid acids are an alternative to PA that does not require humidification and is less prone to leaching. In this study, we prepared two composite membranes by high-temperature impregnation to investigate the effects of the structure of polybenzimidazole (PBI) on the anchoring of solid acids: a laboratory-synthesized m -PBI/CsH 5 (PO 4 ) 2 and the commercial OPBI/CsH 5 (PO 4 ) 2 . Compared to PA-doped membranes, CsH 5 (PO 4 ) 2 -doped membranes showed excellent mechanical properties , particularly m -PBI/CsH 5 (PO 4 ) 2 . Scanning electron microscopy and energy dispersive spectroscopy images showed that CsH 5 (PO 4 ) 2 was uniformly dispersed on the surface and cross-section of both membranes, conducive to the formation of proton transport channels following the CsH 5 (PO 4 ) 2 melting in both samples. The characterization of the physical structures proved the interaction between the imidazole ring and solid acid. Furthermore, the proton conductivity without humidification was similar in m -PBI/CsH 5 (PO 4 ) 2 and OPBI/CsH 5 (PO 4 ) 2 , demonstrating the suitability of m -PBI for fuel cells production. To test this, we assembled a m -PBI/CsH 5 (PO 4 ) 2  cell that showed competitive performances, with a peak power density of 361.28 mW cm −2 at 160 °C in H 2 /O 2 atmosphere.

Crystal structure of tris(2,2′-bipyridine-κ2 N,N′)iron(II) triiodide – dichloromethane (2/1), C61H50Cl2Fe2I12N12

Chuanguo Cui,Jinxiao Zhang,Zhiyin Xiao

C 61 H 50 Cl 2 Fe 2 I 12 N 12 , orthorhombic, Pbcn (no. 60), a  = 13.0247(4) Å, b  = 17.0204(5) Å, c  = 34.1475(9) Å, β = 90, V  = 7570.0(4) Å 3 , Z  = 4, R gt ( F ) = 0.0694, wR ref ( F 2 ) = 0.1605, T  = 293(2) K.