APPLIED CATALYSIS B-ENVIRONMENTAL
·
2021
·
IF 19.503
Shengnan Huang,Fan Tian,Jiawei Dai,Xuesong Tian,Guangfang Li,Yunling Liu,Zhiquan Chen,Rong Chen
Chlorophenols (CPs) treatment in water is a huge challenge due to its native robustness and harmful chlorinated by-products in degradation. In this work, we developed a specific BiO 2-x with high density Bi-O-Bi-O vacancy via a facile hydrothermal process. Extraordinary CPs removal ability under near infrared (NIR, >700 nm) is achieved over the as-prepared product. The presence of vacancies not only induced strong interactions between CPs and photocatalyst, but also promoted singlet oxygen ( 1 O 2 ) and photogenerated holes (h + ) generation. Furthermore, the generated 1 O 2 is found mainly originating from lattice oxygen release and the superoxide radicals ( O 2 − ) oxidation from BiO 2-x . Such performance could be well-maintained under wide pH range as well as in the presence of different constitutes in water matrix. This work unravels a unique function of BiO 2-x photocatalyst for CPs decomposition and provide a rational design of highly efficient photocatalysts toward optimization of pollutants degradations.
研究领域:
环境科学
·
材料科学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Junlei Qi,Minghe Cao,Yiying Chen,Hua Hao,Zhonghua Yao,Hanxing Liu
The effect of sintering atmosphere on the microstructure and dielectric properties of Sr 0.985 Ce 0.01 TiO 3 were investigated in this article. The sample sintered in nitrogen achieves a colossal permittivity (∼12655) and ultralow dielectric loss (0.006) at room temperature and 1k Hz. XRD results reveal that all the samples belong to P m 3 ¯ m space group and no secondary phase is detected. It can be verified by XPS measurement that the nitrogen sintered sample has the highest Ti 3+ content. Five dielectric relaxations can be observed in the dielectric spectroscopy in the test temperature range from −130–500 °C, which can be attributed to the existence of Ti 3+ ions, oxygen vacancies and the other associated defect clusters. Moreover, the off-center Ti 3+ ions make a certain contribution to the high permittivity. The ultralow dielectric loss at room temperature could be ascribed to the formation of defect clusters in the samples sintered in air and nitrogen. These defect clusters which associated with the oxygen vacancy, such as T i 3 + − V O .. − T i 3 + and V S r " − V O ¨ are able to localize charge carriers and restrain the motion and ionization of oxygen vacancies.
研究领域:
材料科学
·
物理学
✓ 已验证
产品关联
DOI
高影响因子
JOURNAL OF ALLOYS AND COMPOUNDS
·
2018
·
IF 3.779
Junlei Qi,Minghe Cao,Yiying Chen,Ying Fang,Wengao Pan,Hua Hao,Zhonghua Yao,Zhiyong Yu,Hanxing Liu
The effects of sintering temperature on microstructure and dielectric properties of Ce doped SrTiO 3 were investigated. The dielectric properties are strongly depend on sintering temperature, the sample sintered at 1520 °C exhibits a colossal permittivity about 7000 at 1 kHz while relative permittivity of the sample sintered at 1380 °C is 770. Further investigations demonstrate that all the samples belong to P m 3 ¯ m space group and without secondary phase. The lattice parameter decrease with the increase of sintering temperature while the mean grain size of SCT (Sr 0.985 Ce 0.01 TiO 3 ) ceramics are increased. Higher sintering temperature helps to improve the dielectric properties which can be attribute to defect clusters (e.g. oxygen vacancies , Ti 3+ /Ti 4+ etc.), however the defects are more likely to become carriers in high electric field which can increase the conductivity and leakage current. With the increase of sintering temperature, the conductivity activation energies , breakdown strength and energy storage density of the samples are decreased.
研究领域:
材料科学
·
电子工程
✓ 已验证
DOI
高影响因子
ACS Applied Electronic Materials
·
2021
·
IF 3.314
Junqing Xiahou,Qi Zhu,Lin Zhu,Siyuan Li,Ji-Guang Li
Modern engineering fields put forward requirements for optical temperature sensors, which need natural-light excitation/storage and near-infrared (NIR) afterglow emission for some special conditions. Here, NIR persistent luminescent phosphors of ZnGa2–x(Mg/Ge)xO4:Cr3+ (x = 0–1.25) have been synthesized. The incorporation of Mg2+/Ge4+ ions in ZnGa2O4:Cr3+ resulted in more defect clusters of “MgGa′–GeGa•” and “ZnGa′–GeGa•” and interstitial oxygens (OInt). Increasing the calcination temperature and Mg2+/Ge4+ doping both contributed to the generation of OInt. Higher efficiency of visible light excitation was observed, mainly due to the defect clusters and OInt. The samples exhibited a bright NIR emission at 695 nm by exposure to UV or visible light, and the NIR signal can last longer than 1 h after the stoppage of excitation. Incorporation of Mg2+/Ge4+ and increasing the calcination temperature both resulted in a deeper trap depth. However, the density of trapped charge carriers takes the dominant role in the persistent luminescence. Therefore, the x = 0.25 sample, having the most trapped charge carriers, exhibits the best afterglow performance. The prepared phosphor exhibited a temperature-dependent persistent luminescence behavior, which can charge natural light and release NIR light repeatedly many times, indicating that they are the potential natural-light rechargeable materials for temperature sensing.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2023
·
IF 5.2
Lu Chen,Sisi Yu,Guichang Shen,Shuai Tang,Tao Zhang,Ji-Guang Li,Qi Zhu
Broadband near-infrared (NIR) phosphors, as key materials in NIR phosphor-converted light-emitting diodes (pc-LEDs) for emerging applications, have recently attracted considerable attention. Herein, by selecting a comprehensive engineering strategy of co-substituting [Al 3+ -Al 3+ ] with [Mg 2+ -Ge 4+ ] units and increasing Cr 3+ concentration, a novel Cr 3+ -doped ZnAl 1.16 Mg 0.4 Ge 0.4 O 4 (ZA(MG) 0.4 :2 at.%Cr 3+ ) phosphor with continual broadband NIR emission was synthesized. The site occupation of Mg 2+ /Ge 4+ in ZnAl 2 O 4 is unraveled by Rietveld structure refinement and density functional theory (DFT) calculations. According to the photoluminescence behaviors, the formed defect clusters of Zn Al ’ -Cr 3+ -Ge Al · and Mg Al ’ -Cr 3+ -Ge Al · can not only introduce shallow defects to serve as new traps to obtain long-persistent luminescence but can also enhance the emission intensity at ∼689 nm and ∼694 nm. The quantity and scale of Cr 3+ -Cr 3+ pairs and Cr 3+ in distorted sites, which can improve the thermal quenching resistance and emission intensity in the range of 700–800 nm, can be accurately regulated by varying the concentration of Cr 3+ . Under 387 nm excitation, the designed material exhibits intensive NIR emission from 685 to 750 nm with a wide full-width at half maximum (FWHM) of 95 nm. The electroluminescence spectrum and potential applications of the NIR pc-LED prepared using ZA(MG) 0.4 :2 at.%Cr 3+ phosphor are also reported. The results promise a feasible strategy to develop NIR phosphors as NIR pc-LEDs lighting sources for applications in non-destructive detection and anti-counterfeiting.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
Advanced Electronic Materials
·
2025
·
IF 5.3
Jian Wang,Zhuowen Zou,Jiajun Zhu,Dandan Gao,Wanbiao Hu
The wealth of complex defects induces attractive functionalities and structural variations in materials. This renders engineering defect states, as well as building up a defect-property relationship, a central subject, but it remains highly challenging because the configurations and charge dynamics of the involved defect systems are hardly explored and thus unclear experimentally. Herein, the defect-dipole-cluster in La-doped CaTiO 3 and, more importantly, its dielectric response process is clarified. Through combined HAADF-STEM, DFT calculation, dielectric, and photoluminescence (PL) spectroscopy, the defect configuration is identified to be V Ca − O − − La Ca type defect-cluster-dipole. The electron–hole recombination from the Ti 3+ and O − states dominates the dielectric relaxation process, as revealed by the similar relaxation frequencies of dielectric response and photoluminescence emission. These findings experimentally demonstrate property tailoring involved in defect-cluster-dipole, providing crucial insights for establishing the defect-property relationship in dielectric materials.
研究领域:
材料科学
·
凝聚态物理
·
电子显微学
✓ 已验证
产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Wei Zhou,Minghe Cao,Hongye Wang,Hua Hao,Zhonghua Yao,Hanxing Liu
The miniaturization of electronic components requires materials with colossal permittivity. In this work, titanium-powder-doped TiO 2 ceramics with colossal permittivity and a low dielectric loss over a wide range of frequency and temperature were successfully prepared using a solid-state reaction in an Ar atmosphere. TiO 2 ceramics with 2% Ti powder doping had the highest permittivity (110,000) and the lowest dielectric loss (0.029) at 1 kHz and room temperature. Systematic defect analysis showed that Ti 4+ was successfully reduced to Ti 3+ through doping with Ti metal powder. Further, oxygen vacancies were created in the high-temperature inert atmosphere, which promoted the formation of defect clusters with T i 3 + − V o ″ − T i 3 + as the core. Polarization and local confinement of the defect clusters resulted in the colossal permittivity and low dielectric loss. Therefore, this work provides necessary information and novel ideas for the design of correlated defects in colossal permittivity materials.
研究领域:
材料科学
·
电气工程
·
陶瓷
·
缺陷工程
✓ 已验证
产品关联
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2022
·
IF 6.888
Kailei Lu,Yucheng Ye,Wenhan Han,Cong Zhang,Lexing Liang,Haifeng Yuan,Yanli Shi,Jianqi Qi,Tiecheng Lu
In the most promising new window materials, the light-blocking property of the state-of-the-art transparent polycrystalline ceramics is still located in the UV range, which undoubtedly limits their applications. Herein, a transparent Y2Zr2O7:Tb (YZO:Tb) ceramic for light-shielding windows was prepared by a solid-state reaction and vacuum sintering method. Two simple and efficient routes, with doping concentrations varying and air-annealing temperatures regulating, were developed for the first time to control the content of defect clusters [TbY4+–O2––TbY4+] and [TbY4+–e•], enabling the optical cutoff waveband of these ceramics spanning from UV and BV to green light. These defect clusters generated from an air-annealing process were proposed for the relevant reaction mechanisms concerning light erasure behavior. The controllably tailoring of optical cutoff wavelength from Tb single-doped YZO ceramics, adjusted by defect clusters, may open a novel door to develop lanthanide-doped transparent ceramics for wide-range tunable light-shielding windows.
研究领域:
材料科学
·
光学材料
·
陶瓷
·
固体物理
·
光屏蔽技术
✓ 已验证
DOI
高影响因子
Nature Communications
·
2025
·Vol. 16
·期 1
·1-14
·
IF 15.7
Zhang Fanxing,Cao Ning,Wang Chentao,Wang Shengxiang,He Yi,Shi Yao,Yan Mi,Bao Ying,Li Zhenglong,Xie Pengfei
Electrochemical CO 2 -to-ethanol conversion is challenged by sluggish C-C coupling kinetics and wide products distribution. Although Cu + has been demonstrated to enhance multi-carbon (C 2+ ) formation, the stabilization of Cu + under reduction conditions is difficult. Here, we report a hydrogen-ethanol pretreatment strategy to obtain Cu nanoparticles covered by highly dispersed and disordered ZnO 1- x clusters. Ethanol-induced ZnO 1- x redispersion gives rise to abundant Cu + on the subsurface. The optimal catalyst delivers a 73.0% ethanol Faradaic efficiency (FE) and 86.0% total C 2+ FE at −0.9 V, with a 2.3 mmol cm −2 h −1 ethanol formation rate and single-pass ethanol yield of 18.0%. The catalyst also exhibits stability beyond 500 h, attributed to the stabilization of Cu + by the ZnO 1- x shield that requires a high energy barrier for lattice oxygen removal. In situ X-ray spectroscopy and calculations reveal a volcano relationship between Cu + ratio in Cu species and ethanol FE. Optimal Cu + density not only facilitates *OC-COH coupling but also optimizes the adsorption energy of *CH 2 CH 2 O on catalyst for ethanol electrosynthesis.
研究领域:
电化学
·
催化
·
材料科学
·
环境化学
·
能量转换
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）