RSC Advances
·
2022
·Vol. 12
·期 19
·12219-12225
·
IF 4.036
Yang Song,Yuchong Kang,Wei Ma,Haibo Li
Herein, a facile one-step method is developed to in situ prepare crystalline anatase and rutile TiO2 nanocrystals on Ti3C2Tx by regulating the metastable Ti ions. The combination of TiO2 nanocrystals and Ti3C2Tx not only introduces extensive accessible sites for Na+ storage, but also promotes the charge transport by efficiently relieving the collapse of Ti3C2Tx. Compared with pristine Ti3C2Tx, the optimized TiO2/Ti3C2Tx hybrid electrode (anatase/rutile-TiO2/Ti3C2Tx, A/R-TiO2/Ti3C2Tx) exhibits a desirable specific surface area (22.5 m2 g−1), an ultralow charge transfer resistance (42.46 Ω) and excellent ion diffusion (4.01 × 10−14). Remarkably, rich oxygen vacancies are produced on TiO2/Ti3C2Tx which is beneficial to enhance the insertion/de-insertion of Na+ during the charge/discharge process. As a result, the A/R-TiO2/Ti3C2Tx delivers a high average capacity of 205.4 mA h g−1 at 100 mA g−1 and a desirable capacitance retention rate of 84.7% can be achieved after 600 cycles at 500 mA g−1.
研究领域:
材料科学
·
能源科学
✓ 已验证
DOI
高影响因子
Frontiers in Chemistry
·
2022
·
IF 5.545
Wu Jinming,Zhang Yongqiang,Yang Shuang,Chen Zhaolai,Zhu Wei
Metal halide perovskite single-crystal detectors have attracted increasing attention due to the advantages of low noise, high sensitivity, and fast response. However, the narrow photoresponse range of widely investigated lead-based perovskite single crystals limit their application in near-infrared (NIR) detection. In this work, tin (Sn) is incorporated into methylammonium lead iodide (MAPbI3) single crystals to extend the absorption range to around 950 nm. Using a space-confined strategy, MAPb0.5Sn0.5I3 single-crystal thin films with a thickness of 15 μm is obtained, which is applied for sensitive NIR detection. The as-fabricated detectors show a responsivity of 0.514 A/W and a specific detectivity of 1.4974×1011 cmHz1/2/W under 905 nm light illumination and –1V. Moreover, the NIR detectors exhibit good operational stability (∼30000 s), which can be attributed to the low trap density and good stability of perovskite single crystals. This work demonstrates an effective way for sensitive NIR detection.
研究领域:
材料科学
·
光学工程
✓ 已验证
DOI
高影响因子
Energetic Materials Frontiers
·
2023
·
IF 0
Yu-shu Xiong,Yong-qi Wang,Chong Wan,Wen-zhen Zhang,Zhao Qin,Su-hang Chen,Kang-zhen Xu
To overcome the agglomeration and insufficient combustion of nano-boron (n-B) powders, this study successfully prepared two novel types of boron-based nanocomposites using the acoustic resonance technology, namely high-substitute nitrochitosan/nano-boron (NCh-B) with ratios of 1:3, 1:5, 1:7 and 1:9, and nitrochitosan/nano-boron powder/nano-titanium (NCh-B-Ti) with Ti contents of 5 wt%, 10 wt%, 15 wt% and 20 wt%. The structural morphologies, laser ignition and combustion properties of the composites were systematically investigated. The results suggest that the addition of NCh can significantly improve the dispersion of n-B. NCh-B exhibited a higher combustion performance than n-B, as evidenced by their ignition delay and flame areas. When the laser power density was 81 W, NCh-B 5 -Ti 15% exhibited a combustion time and an ignition delay of 240 ms and 5.5 ms respectively, which were higher and lower than those of NCh-B 5 (199 ms and 17 ms, respectively). Furthermore, NCh-B 5 -Ti 15% displayed a lower ignition delay than both n-B powders (12 ms) and NCh-B (11 ms), as well as brighter flames and a larger combustion area. Therefore, the addition of n-Ti can promote the combustion of n-B powders, with the combustion products of NCh-B-Ti including H 3 BO 3 , B 2 O 3 , TiB 2 , and TiO. This study provides a new method for improving the ignition performance and combustion efficiency of n-B powders.
研究领域:
材料科学
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燃烧学
✓ 已验证
DOI
MATERIALS CHARACTERIZATION
·
2020
·
IF 3.562
Yuping Wang,Shuying Shi,Qing Dong,Chonghe Xu,Silun Zhu,Xiaoqian Zhang,Yuk Tak Chow,Xinqiang Wang,Guanghui Zhang,Luyi Zhu,Dong Xu
As the pillar material of the electronic ceramic industry, BaTiO 3 (BTO) has superior dielectric and piezoelectric properties . In this present work, pure phase BTO and lanthanum-doped Ba (1–x) La x TiO 3 (BL x T) fibers (x=0.003, 0.006, 0.009 and 0.012) were prepared by electrospinning method with polyacetylacetonatotitanate (PAT). All the fibers after heat-treatment were tetragonal phase with good crystallinity; additionally, the tetragonal phase BTO ceramics have better dielectric properties than the cubic ones. BTO fiber (BTOF) and powder (BTOP) were pressed and sintered into ceramic sheets with BTOF having better formability. Compared with BTOP ceramics, BTOF ceramics had obvious micro-capacitance effect, so they had higher dielectric constants at low frequencies (f < 3000 Hz). Therefore, BTOF ceramics were excellent low frequency capacitor materials which could be applied to low frequency filters. The BTOFs were doped with La 3+ to further improve the dielectric properties. When the doping concentration was 0.9%, the dielectric constant of BL x T fiber ceramics reached the maximum value of 5100 (25 °C, f = 100 Hz). The downward trend of Curie temperature was more uniform with the increase of La 3+ doping amount, pointing to obvious advantages in the manufacturing of temperature-controlled capacitors.
研究领域:
电子陶瓷
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材料科学
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介电材料
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DOI
高影响因子
ACS Applied Optical Materials
·
2024
·
IF 0
Min Yang,Xi Wang,Nan Li,Jiatian Cheng,Chengzhi Xue,Ziwei Xu,Depeng Chu,Xiaojie Zhang,Yucheng Liu,Zhou Yang,Shengzhong Frank Liu
Due to their exceptional responses to X-ray exposure, lead halide perovskites are recognized as ideal candidates for high-spatial-resolution X-ray detectors. However, an effective method to deposit a large-area, submillimeter-thick, dense perovskite film for X-ray detection has been lacking. In this study, a strategy that combines saturated-solution-induced epitaxial growth with a large-area blade-coating process has been developed to produce large-size, submillimeter-thick CH3NH3PbBr3 perovskite films. The successive deposition of a saturated precursor film does not dissolve the underlying perovskite film. Instead, it promotes epitaxial crystal growth by controlling the crystal growth rate over the nucleation rate. The obtained films exhibit a columnar grain structure with fewer pinholes and negligible residual lattice strain. As a result, under an X-ray source with a working voltage of 40 kV, the obtained thick CH3NH3PbBr3 film achieves X-ray sensitivity of up to 1938 μC Gyair–1 cm–2 under −3 V bias, a reduced dark current drift of 1.78 × 10–4 nA s–1 V–1, and a detection limit of 47 nGyair s–1 under a −2 V bias; all the above are among the best performances reported for the CH3NH3PbBr3-based X-ray detectors. Using the point-to-point current scanning method, a clear X-ray image could be obtained. This study presents an effective approach for producing thick, dense, and crack-free perovskite films directly on substrates for future X-ray detection applications.
研究领域:
材料科学
·
核医学成像
✓ 已验证
DOI
Journal of Materiomics
·
2024
·
IF 8.4
Zhenfeng Guo,Ze Zhu,Xiaoqian Zhang,Ying Peng,Ziting Huang,Xinqiang Wang,Luyi Zhu,Yongshuai Xie,Guanghui Zhang,Benxue Liu,Dong Xu
High-performance thermally insulating ceramic materials with excellent mechanical and thermal insulation properties are essential for thermal management in extreme environments. In this work, SiO 2 was introduced into the crystalline lattice and grain boundary of TiO 2 to inhibit its phase transition and grain growth. Meanwhile, layered TiO 2 /SiO 2 nanofiber membranes (TS NFMs) were designed and prepared. The TS NFMs had lightweight (44 mg/cm 3 ), high tensile strength (4.55 MPa), ultra-flexibility, and low thermal conductivity (31.5 mW·m −1 ·K −1 ). The prepared TS-1100 NFMs had excellent buckling fatigue resistance, which could undergo 100 buckling-recovery cycles at up to 80% strain. Low density and high diffuse reflectance endow the TS NFMs with excellent thermal insulation effects. A single-layer nanofiber membrane was composed of multiple layers of nanofibers. According to the principle of multi-level reflection, the multilayer structure had a better near-infrared reflection effect. Through the stacking effect of layers, a 10 mm thick sample composed of about 300 layers of nanofiber membranes could reduce the hot surface temperature from 1,200 °C to about 220 °C, demonstrating an excellent comprehensive thermal insulation effect. The layered TS NFMs with ultra-flexibility, high tensile strength and high-temperature resistance (1,100 °C) provide a dominant pathway in producing materials in extremely high-temperature environments.
研究领域:
材料科学
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热管理工程
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
·
2024
·
IF 3.3
Daqian Wu,Fengxian Zhou,Kai Feng,Jun Wang,Qixuan Lu,Xiaowu Wang,Zijun Zhan,Weiwei Chen,Zhengzheng Liu,Zeyu Zhang,Zhiping Hu,Juan Du
Lead halide perovskite quantum dots (QDs) have garnered significant attention due to their tunable band gaps, unique quantum confinement effects, and high photoluminescence quantum yields (PLQYs). Among them, Organic-inorganic QDs make them promising candidates for optoelectronic devices such as quantum dot light-emitting diodes (QLEDs), solar cells, lasers, and photodetectors. However, the toxicity of lead (Pb) has raised environmental and health concerns, hindering their industrial application. To alleviate concerns about heavy metals Pb, extensive research has been conducted on B-site doping and the development of lead-free perovskites. Herein, we firstly developed B-site doping strategy on organic-inorganic hybrid perovskite QDs via rare-earth elements. Neodymium (III) (Nd 3+ ) doped FAPbBr 3 QDs were prepared through the ligand-assisted reprecipitation method at room temperature. The B-site doping strategy could alleviate the heavy metal problem of Pb and modulate the band gap of FAPbBr 3 QDs facilely. The results demonstrated that increasing the concentration of Nd³⁺ can change the emission of FAPbBr₃ QDs from pure green to deep blue. Specifically, we achieved highly pure blue emission (∼438 nm) with a full width at half maximum (FWHM) of 13 nm for Nd³⁺-doped FAPbBr₃ QDs. Time-resolved photoluminescence (TRPL) spectroscopy revealed a decrease in the lifetime of FAPbBr₃ QDs from 22.86 to 15.46 ns as the doping concentration increased. Additionally, we fabricated a white LED (WLED) utilizing blue-emitting Nd³⁺-doped FAPbBr₃, green-emitting FAPbBr₃ QDs, and red QDs, achieving a white emission color coordinate of (0.33, 0.36). This study pioneers the application of B-site rare-earth doping in organic-inorganic hybrid perovskite QDs, demonstrating that B-site composition engineering is a reliable strategy to further exploit the perovskite family for wider optoelectronic applications.
研究领域:
材料科学
·
光学工程
·
电子工程
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2020
·
IF 2.779
Xibing Li,Huijie Yang,Nan Ding,Wentao Huang,Xiaoyue He,Mingxun Yu,Lixi Wang,Qitu Zhang
A series of double perovskite (Gd 0.85- x Lu x ) 2 MgTiO 6 : 0.3Eu 3+ red phosphors were prepared via a typical high temperature solid-state reaction. XRD and HRTEM exhibits that the phosphors well crystallized as a double perovskite with the space group of P21/n symmetry. The luminescent properties of samples were investigated via excitation and emission spectra . The phosphors emit strong red light and weak orange red light under ultraviolet (UV) and near-UV excitation suggesting that Eu 3+ ions situated in the sites without inversion symmetry. The UV–vis spectra included a broad host absorption band assigned to O 2- -Eu 3+ and some peaks at 395 nm, 465 nm and 533 nm attributed to the typical f-f transition of Eu 3+ . The CIE chromaticity coordinates of all samples were near to the standard red light, indicating that the (Gd 0.85- x Lu x ) 2 MgTiO 6 : 0.3Eu 3+ was a potential candidate material for red emitting phosphors. The decay curves matched with the lines fitted by a one exponential decay formula and the decay time increased with increasing Lu 3+ -dopant concentration within x < 0.8. The temperature-dependent emission spectra from 298 K to 473 K were used to evaluate the thermal stability of Gd 0.9 Lu 0.8 Eu 0.3 MgTiO 6 phosphors and the activation energy of Gd 0.9 Lu 0.8 Eu 0.3 MgTiO 6 for 5 D 0 - 7 F 2 transition was calculated to be 0.158eV. The results revealed that the phosphors have the excellent thermal stability and were promising material for applications in LEDs.
研究领域:
材料科学
·
光学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2021
·
IF 4.527
Ping Gong,Yan Li,Chenxing Xin,Qiaoyu Chen,Liang Hao,Qinglei Sun,Zheng Li
An effective method to fabricate barium titanate (BTO)/carbonyl iron powder (CIP) composites with enhanced microwave absorption (MA) performance was prepared via multimaterial digital optical processing (DLP) 3D printing technique. The bilayer-gradient honeycomb structural absorber (BGHSA) with adjustable broadband can be obtained by leveraging of varying compositional and structural design (layered thickness ratios , and gradient structures). The optimal reflection loss ( R L ) value and effective bandwidth of BGHSA can reach −51 dB and 15.4 GHz, respectively, exhibiting a distinct improvement ( R L increased by 32.4% and effective bandwidth by 42.9%) compared with the reference. The highly improved performances especially in the broadband absorption (15.4 GHz) were mainly attributed to the better impedance matching and waves multi-reflections. This work provides a promising strategy to fabricate functionally graded materials for potential application in the absorption of electromagnetic waves .
研究领域:
材料科学
·
电磁学
✓ 已验证
DOI
高影响因子
CHINESE PHYSICS LETTERS
·
2017
·Vol. 34
·期 6
·068103
·
IF 0.8
Wen-Rong Xie,Bin Liu,Tao Tao,Guo-Gang Zhang,Bao-Hua Zhang,Zi-Li Xie,Peng Chen,Dun-Jun Chen,Rong Zhang
A sequential deposition method is developed, where the hybrid organic–inorganic halide perovskite (CH3NH3Pb (I1−xBrx)3) is synthesized using precursor solutions containing CH3NH3I and PbBr2 with different mole ratios and reaction times. The perovskite achieved here is quite stable in the atmosphere for a relatively long time without noticeable degradation, and the perovskite nanowires are proved to be single crystalline structure, based on transmission electron microscopy. Furthermore, strong red photoluminescence from perovskite is observed in the wavelength range from 746 nm to 770 nm with the increase of the reaction time, on account of the exchanges between I− ions and Br− ions in the perovskite crystal. Lastly, the influences of concentration and reaction time of the precursor solutions are discussed, which are important for evolution of hybrid perovskite from nanocuboid to nanowire and nanosheet.
研究领域:
材料科学
·
纳米技术
✓ 已验证
DOI
高影响因子
Small
·
2020
·Vol. 16
·期 26
·2000030
·
IF 11.459
Yaru Liang,Xiang Xiong,Zhuijun Xu,Qingbing Xia,Liyang Wan,Rutie Liu,Guoxin Chen,Shu-Lei Chou
Lithium-ion batteries (LIBs) have been widely applied and studied as an effective energy supplement for a variety of electronic devices. Titanium dioxide (TiO 2 ), with a high theoretical capacity (335 mAh g −1 ) and low volume expansion ratio upon lithiation, has been considered as one of the most promising anode materials for LIBs. However, the application of TiO 2 is hindered by its low electrical conductivity and slow ionic diffusion rate. Herein, a 2D ultrathin mesoporous TiO 2 /reduced graphene (rGO) heterostructure is fabricated via a layer-by-layer assembly process. The synergistic effect of ultrathin mesoporous TiO 2 and the rGO nanosheets significantly enhances the ionic diffusion and electron conductivity of the composite. The introduced 2D mesoporous heterostructure delivers a significantly improved capacity of 350 mAh g −1 at a current density of 200 mA g −1 and excellent cycling stability, with a capacity of 245 mAh g −1 maintained over 1000 cycles at a high current density of 1 A g −1 . The in situ transmission electron microscopy analysis indicates that the volume of the as-prepared 2D heterostructures changes slightly upon the insertion and extraction of Li + , thus contributing to the enhanced long-cycle performance.
研究领域:
材料科学
·
能源存储
✓ 已验证
DOI
高影响因子
Advanced Photonics Research
·
2022
·Vol. 3
·期 12
·2200197
·
IF 0
Heng Guo,Qingxian Zhao,Peng Ran,Jinping Chen,Yizhi Zhu,Qingsong Jiang,Yuling Tang,Zhenhua Zhang,Lei Song,Chunxiang Xu,Shouhua Luo,Zengliang Shi
Scintillator is a critical component to detect high-energy particles or rays, which is widely used in deep space exploration, security inspection, and nondestructive testing and medical diagnosis, such as X-ray imaging and computed tomography (CT). However, the wider application of traditional inorganic and organic scintillators is limited by the complex operation process or poor adaptability to changeable environment, and there remains a demand to develop green and stable scintillators with high sensitivity and low detection limit. Herein, the one-step preparation of lead-free perovskite Cs 3 Cu 2 I 5 scintillator film for high-definition X-ray imaging by conventional chemical vapor deposition method is reported. Cs 3 Cu 2 I 5 demonstrates good stability and bright-blue emission at 445 nm and superhigh photoluminescence quantum yield (85.14%). Importantly, upon X-ray irradiation, the Cs 3 Cu 2 I 5 perovskite film exhibits light yield (≈39 251 photons MeV −1 ) as high as two times of the commercially available Ce:LuAG single-crystal scintillator (≈22 000 photons MeV −1 ). Furthermore, the practical demonstration for a bamboo stick and insect specimens illustrates sensitive scintillation response to X-ray signals with superior linearity and high-quality images in X-ray photography and CT. Overall, Cs 3 Cu 2 I 5 film provides nontoxicity, high radioluminescence intensity, and good stability, it can be regarded as a competitive material for X-ray imaging.
研究领域:
材料科学
·
医学影像
·
辐射探测
✓ 已验证
DOI
危险品化学品经营许可证（带存储）