JOURNAL OF ALLOYS AND COMPOUNDS
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2020
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IF 4.65
Yi Cao,Peiyuan Tang,Yue Han,Wenfeng Qiu
In this study, we succeed to synthesize the lanthanum titanate (LTO) flexible self-supporting film, and the flexible electrode based on the self-supporting film as active material were also provided to verify the electrochemical energy storage performance. The self-supporting film with both excellent flexibility and outstanding crystalline structure has been prepared by electrospinning combined with calcination method. To further optimize calcination processing, the microstructure, morphological characteristics and lattice structure of the self-supporting films can be explored by using SEM、TG、XRD and FT-IR. What’s more, the electrochemical properties of the flexible electrode prepared by LTO self-supporting film have been determined in various solutions. Comparing with the other aqueous, the highest areal capacitance of 806.2 mF cm −2 at 2 mA cm −2 was got form 1 M Na 2 SO 4 aqueous electrolyte. Moreover, the symmetrical LTO//LTO flexible device fabricated by two LTO electrodes has a maximum areal capacitance of 149.2 mF cm −2 at a current density of 2 mA cm −2 with a high cell voltage of 2.1 V. As the result of that, this device exhibits a high energy density of 91.4 μWh·cm −2 at a low power density of 2.1 mW cm −2 with outstanding cycling life and excellent bending stability. Therefore, the LTO self-supporting film can be considered as a prospective material for wearable energy storage device.
研究领域:
材料科学
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能源技术
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产品关联
DOI
高影响因子
SENSORS
·
2025
·Vol. 25
·期 3
·901
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IF 3.5
Jian Wang,Caicai Sun,Jusheng Bao,Zhiwei Yang,Jian Zhang,Xiao Huang
Simple SummaryIn this work, Y-doped LTO nanosheets were synthesized for NO2gas sensing under different humidity conditions. These materials showed increased responses at higher humidity levels due to enhanced proton conduction and NO2-assisted proton generation. Notably, Y-doped LTO nanosheets exhibited higher responses than pure LTO, as Y-doping created more oxygen vacancies, improving water adsorption and proton dissociation.Water molecules from the environment or human breath are one of the main factors affecting the accuracy, efficiency, and long-term stability of electronic gas sensors. In this contribution, yttrium (Y)-doped La2Ti2O7(LTO) nanosheets were synthesized by a hydrothermal reaction, demonstrating improved proton conductivity compared to their non-doped counterparts. The response of Y-doped LTO with the optimal doping concentration to 100 ppm NO2at 43% relative humidity (RH) was −21%, which is four times higher than that of bare La2Ti2O7. As the humidity level increased to 75%, the response of Y-doped LTO further increased to −64%. Unlike the gas doping effect observed in previous studies of semiconducting metal oxides, the sensing mechanism of Y-doped LTO nanosheets is based on the enhanced dissociation of H2O in the presence of target NO2molecules, leading to the generation of more protons for ion conduction. This also resulted in a greater resistance drop and thus a larger sensing response at elevated humidity levels. Our work demonstrates that proton-conductive oxide materials are promising gas-sensing materials under humid conditions.
研究领域:
材料科学
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化学
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DOI
PubMed
高影响因子
JOURNAL OF RARE EARTHS
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2024
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IF 5.2
Chunqing Fu,Wei Meng,Xiaoyan Fu,Shuya Wang,Wenzhi Sun,Hongwu Zhang
X-ray irradiated La 2 Ti 2 O 7 :Pr 3+ was found to show long-time sustainable mechanoluminescence (ML), which can realize the high sensitivity and real time detection of stress burst for more than 72 h. Under the excitation of X-ray, La 2 Ti 2 O 7 :Pr 3+ shows red ML emissions located at 610, 624 and 638 nm, which are similar to the afterglow emission spectrum and can be ascribed to 1 D 2 - 3 H 4 , 3 P 0 - 3 H 4 and 3 P 0 - 3 H 2 of Pr 3+ . And the linear increases of compressive load can induce the linear increases of ML intensity of the sample, indicating that the X-ray induced ML emission can be utilized to accurately detect the stress applied on the object. Furthermore, X-ray irradiated La 2 Ti 2 O 7 :Pr 3+ possesses excellent stability and the repeatability of ML emission and the ML signals can keep stable even 50 load cycles after 1 h decay. The thermoluminescence results suggest that abundant electrons are trapped in shallow and deep answered for stable ML emission. More importantly, the deeply trapped electrons induced ML emissions from X-ray irradiated La 2 Ti 2 O 7 :Pr 3+ can be utilized to detect the stress bursts for a long time. When the sample is recharged by 5 min X-ray irradiation once, within 24 h decay, the 1500 N burst among many 1000 N cycles can be clearly detected, and the signal to noise ratio (S/N) reaches 1.32 and 1.26 after 12 and 24 h decay, respectively. And even after 72 h decay, the S/N of 2500 N still arrives at 1.23 and that of 4000 N reaches 1.97, indicative of long-time high sensitivity detection of abnormal stress. All these results suggest that the X-ray-irradiated La 1.97 Ti 2 O 7 :0.03Pr 3+ /resin sample can realize the high sensitivity and real time detection of stress burst for more than 72 h, which thus possesses great potential application in early warning of the emergency disasters such as bridge fracture, tunnel collapse and so on.
研究领域:
材料科学
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光学
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物理学
✓ 已验证
DOI
高影响因子
ACS Omega
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2020
·
IF 2.87
Yi Cao,Peiyuan Tang,Wenfeng Qiu,Tong Zhao
Flexible all-solid-state supercapacitors have drawn more attention owing to the rapid growth of wearable electronic equipments. Herein, we have succeeded in synthesizing a series of Y-doped lanthanum titanate flexible self-supporting films (LSF-x, 0.1 ≤ x ≤ 0.5) and investigating the change of microstructures, morphological characteristics, and lattice structures of these films affected by different Y-doping contents. To further determine the optimum Y-doping content, we have explored the electrochemical properties of working electrodes prepared by LSF-x (0.1 ≤ x ≤ 0.5) samples as the main active material. As the LSF-0.2 electrode has the best areal capacitance of 1.3 F·cm–2 at 2 mA·cm–2, we use the LSF-0.2 electrodes and PVA–Na2SO4 gel to fabricate a flexible all-solid-state supercapacitor device. This device has a high areal capacitance of 255.9 mF·cm–2 at a current density of 2 mA·cm–2 with a high cell voltage of 2.1 V, while the corresponding energy density is 156.8 μWh·cm–2 with a power density of 2.1 mW·cm–2. Moreover, it also shows a long cycling life and outstanding flexibility. Therefore, the LSF-0.2 sample can be used as an excellent energy-storage material for a wearable electronic device.
研究领域:
材料科学
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能源技术
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纳米科技
✓ 已验证
DOI
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
·
IF 14.229
Erbing Hua,Shu Jin,Xiaorong Wang,Shuang Ni,Gang Liu,Xiaoxiang Xu
In this work, novel 2D type-II p-n heterojunctions La 2 Ti 2 O 7 /In 2 S 3 have been fabricated. The heterojunctions exhibit much improved photocatalytic activity over individual moieties and their physical mixtures in which 18-fold increment in hydrogen production has been achieved under visible light illumination (λ ≥ 400 nm). Their superior activities stem from intimate face-to-face contact between La 2 Ti 2 O 7 and In 2 S 3 in the heterojunctions which guarantee facile charge interchange. Photoelectrochemical analysis suggests that efficient charge separations occur at the interfaces of the heterojunctions and contributes to a prolonged charge lifetime as well as the much enhanced photocatalytic activities. Such a simple strategy by fabricating ultrathin type-II p-n heterojunctions also warrant promising applications in other areas such as optoelectronics, sensors etc. whereby efficient charge separations are needed.
研究领域:
材料化学
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光催化
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纳米材料
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能源科学
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半导体物理
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环境催化
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可持续能源
✓ 已验证
DOI
高影响因子
JOURNAL OF LUMINESCENCE
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2022
·
IF 4.171
Yi Zhang,Cuiping Zhou,Qifeng Zhang,Pengfei Yin,Xiyuan Sun,Kaiming Wang,Jian Wang,Xing Feng
In this paper, a synthesized material change from perovskite-layer-structured La 2 Ti 2 O 7 to perovskite type LaTiO 3 induced by Li 2 CO 3 addition was observed. The [TiO 6 ] octahedral site symmetry and particle uniformity showed an obvious variation with the change from La 2 Ti 2 O 7 to LaTiO 3 . A broadband far-red emission from 670 to 780 nm emerged when Mn 4+ , Li + ions were co-doped. Furthermore, (Mn 4+ , Li + ) co-doped LaTiO 3 phosphor can be effectively excited by near-UV and blue lights, which is suitable for combining with commercial InGaN LED chips. The LaTiO 3 :0.4%Mn 4+ , 150%Li + phosphor exhibited a high quantum efficiency of 71.1% and a good thermal stability with emission intensity retained 65% at 423 K. Finally, a LED device was fabricated with the LaTiO 3 :0.4%Mn 4+ , 150%Li + phosphor, which matches well with the absorption of photochrome of P FR and shows a good potential for use in agricultural cultivation fields.
研究领域:
材料科学
·
农业科学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2025
·
IF 5.6
Dong Yi,Jiawei Fu,Fenzhong Long,Jin Han,Fangui Meng,Xinmin Zhang
To improve the quality of white LED and develop plant growth lighting, considerable efforts have been devoted to investigating red phosphor. Eu 3+ -activated phosphors are well-known red-emitting components due to their 5 D 0 - 7 F 1,2 transitions in various applications. It is also found that its 5 D 0 - 7 F 4 transition in the range of far-red wavelengths has potential applications in the fields of daily and agricultural lighting. In this study, two kinds of Eu 3+ -doped layered perovskite La 2 Ti 2 O 7 and A 2 La 2 Ti 3 O 10 (A = Li, Na, K) phosphors were synthesized by the solid-state method. The crystal structure, absorption, excitation, and emission spectra of all the samples were investigated in detail. Dissimilar luminescent behaviors of the studied samples were observed. Due to the different crystal structure and chemical composition of the host matrix, each compound exhibits a different emission spectrum. Specifically, Eu 3+ occupies a lower symmetric La 3+ site in A 2 La 2 Ti 3 O 10 (A = Li, Na, K) phosphors, resulting in an intense 5 D 0 - 7 F 4 far-red emission, while in La 2 Ti 2 O 7 :Eu 3+ , Eu 3+ gives a weak 5 D 0 - 7 F 4 emission. To the best of our knowledge, this is the first report that Eu 3+ exhibits a strong 5 D 0 - 7 F 4 far-red emission in the titanate host lattices with perovskite structure. Besides, A 2 La 2 Ti 3 O 10 :Eu 3+ (A = Li, Na, K) phosphors achieve higher photoluminescence efficiency than La 2 Ti 2 O 7 :Eu 3+ . Among them, the internal quantum efficiency of the optimized Li 2 La 2 Ti 3 O 10 :1.2Eu 3+ is about 84.7 %, and it has a better thermal stability (80 % at 125 °C). Furthermore, good photoelectric performances of red/white-LEDs fabricated by utilizing the representative Li 2 La 2 Ti 3 O 10 :1.2Eu 3+ as red/far-red components indicate that it has potential applications in indoor/outdoor lighting and plant growth lighting. This study provides a feasible way for developing efficient Eu 3+ -activated far-red optical materials.
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产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）