APPLIED CATALYSIS B-ENVIRONMENTAL
·
2019
·
IF 14.229
Wen Cui,Lvcun Chen,Jieyuan Li,Ying Zhou,Yanjuan Sun,Guangming Jiang,S.C. Lee,Fan Dong
Semiconductor-based photocatalysis has attracted considerable interdisciplinary attention for its diverse applications in environmental remediation and solar energy conversion. However, pure earth-abundant insulators have been seldom considered as photocatalysts because of the unfeasible electronic excitation. In this work, we make the earth-abundant insulator BaSO 4 as conceptually new photocatalyst via Ba-vacancy engineering for the first time. The BaSO 4 with Ba-vacancy is synthesized by a facile precipitation method and applied for photocatalytic NO removal in air. XAFS spectroscopy and DFT calculations demonstrate the formation of Ba-vacancy. Also, defect level induced by Ba-vacancy between the wide band gap is demonstrated, which endows insulator BaSO 4 with semiconductor-like photocatalytic performance. Besides, according to the TPD analysis and theoretical simulation, Ba species is functioned as the NOx storage center for the primary accumulation of NO molecule on substrate, and simultaneously Ba-vacancy is equipped with the capability to redistribute charge carriers and thus accelerate the activation of NO molecule by the donation of electrons to electron-deficient areas, facilitating the conversion of NO into a higher valance state for further favorable photocatalytic oxidation. In situ DRIFTS spectra are applied to dynamically monitor intermediates and products on photocatalyst surface, revealing the reaction process and the enhancement role of Ba-vacancy. This work opens a new research doorway on earth-abundant insulators for the development of a new family of photocatalyst.
研究领域:
材料科学
·
环境科学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Wengao Pan,Qingping Lin,Lili Xiao,Shihao Feng,Ying Li,Jie Gao,Pengfei Yue,Guoshang Zhang
Perovskite structural LiBaF 3 ceramics with excellent microwave dielectric properties were synthesized using traditional solid-state method. By regulating the sintering temperatures from 600 °C to 675 °C, LiBaF 3 ceramics exhibit tunable dielectric constant ( ε r ) from 12.42 to 13.72, adjustable Q × f value from 55000 GHz to 73000 GHz, and regulable temperature coefficient of resonance frequency ( τ f ) from −36.78 ppm/°C to −34.68 ppm/°C. The properties are strongly associated with the density, and can be further optimized by 0.5 wt%TiO 2 addition ( ε r = 14.43, Q × f = 56000 GHz, τ f = -1.26 ppm/°C). The LiBaF 3 ceramics also exhibit excellent compatibility with Ag and Al electrodes. Furthermore, relationships between multiscale structures and microwave dielectric properties of the ceramics were revealed. Oxidation behaviors between LiBaF 3 and O 2 would result in the lattice shrinkage, the introduction of defect level, the decrease of bandgap and density, and then deteriorating the microwave dielectric properties. All the findings make the LiBaF 3 ceramic a promising candidate for ULTCC application, and may facilitate the development of other novel microwave dielectric materials.
研究领域:
材料科学
·
电子工程
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产品关联
DOI
高影响因子
Small
·
2024
·Vol. 20
·期 31
·2309034
·
IF 13
Sheng Wu,Binli Xiao,Dongliang Jiang,Yao Xiao,Peishan Shao,Zhiyao Zhou,Yinzhen Wang,Puxian Xiong
Mechanoluminescence (ML) materials are featured with the characteristic of “force to light” in response to external stimuli, which have made great progress in artificial intelligence and optical sensing. However, how to effectively enable ML in the material is a daunting challenge. Here, a Lu 3 Al 2 Ga 3 O 12 :Cr 3+ (LAGO: Cr 3+ ) near infrared (NIR) ML material peaked at 706 nm is reported, which successfully realizes the key to unlock ML by the lattice-engineering strategy Ga 3+ substitution for Al 3+ to “grow” oxygen vacancy (O v ) defects. Combined with thermoluminescence measurements, the observed ML is due to the formation of defect levels and the ML intensity is proportional to it. It is confirmed by X-ray photoelectron spectroscopy and electron paramagnetic resonance that such a process is dominated by O v , which plays a crucial role in turning on ML in this compound. In addition, potential ML emissions from 4 T 2 and 2 E level transitions are discussed from both experimental and theoretical aspects. This study reveals the mechanism of the change in ML behavior after cation substitution, and it may have important implications for the practical application of O v defect-regulated turn-on of ML.
研究领域:
材料科学
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凝聚态物理
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光学功能材料
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缺陷化学
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传感技术
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DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2020
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IF 7.632
Yuan Lin,Qiao Zhang,Yuhang Li,Yunpeng Liu,Kejia Xu,Jiangnan Huang,Xiaosong Zhou,Feng Peng
An incompletely covered CdS/ZnS core/shell is synthesized via a simple hydrothermal method. Due to the defect energy levels introduced by zinc vacancies, the typical type-I heterojunction of CdS/ZnS evolves to a type-II heterojunction and Z-scheme hybrid structure so that the ZnS shell can timely transfer and capture the photogenerated holes from the CdS core. The surface photovoltage (SPV) distribution caused by photogenerated charges on the surface of catalyst is visually presented by Kelvin probe force microscopy with synchronous illumination (microscope SPV). It intuitively proves the effective spatial separation of photogenerated holes from the CdS core to the ZnS shell, for the first time. Under optimal conditions, the highest hydrogen production rate of CdS/ZnS reached 24.1 mmol g–1 h–1 under visible light illumination. The average apparent quantum yield of 9.3% can be achieved for 9 h of illumination (λ = 420 ± 5 nm). It exhibits highly efficient photocatalytic H2 evolution with well stability.
研究领域:
材料科学
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能源科学
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产品关联
DOI
高影响因子
Advanced Optical Materials
·
2024
·
IF 8
Junqing Xiahou,Li Cao,Sai Huang,Tao Zhang,Ji-Guang Li,Qi Zhu
Recently, combining long afterglow materials with organic fluorescent dyes, particularly carbon dots (CDs) to produce heterojunction and improve its luminescence and persistence properties became an important research direction. However, the precise role of these internal defects in the energy transfer process of CD@inorganic matrix composite fluorescent materials has not been thoroughly discussed. Establishing matching trap level to promote the energy transfer between the trap level and CDs level not only helps to enhance the afterglow performance, but also can explain the heterogeneous structure interaction between organic–inorganic fluorescent materials. Herein, ZLAGC@CDs luminescent composite is successfully synthesized via coating CDs on Zn 1- x (Li/Al) x Ga 2 x O 4 :0.005Cr 3+ (ZLAGC, x = 0–1), which exhibits a unique double emission at ≈430 nm (the defect luminescence of CDs) and 718 nm (the 2 E→ 4 A 2 transition of Cr 3+ ). After coating, the energy transfer from the defect level of CDs to the excited state of Cr 3+ enhanced the NIR emission. The electron transfer between the defect level of CDs and the split deeper trap level of ZLAGC also improved the visible and near-infrared (NIR) afterglow. The fluorescence and afterglow signals of ZLAGC@CDs are highly sensitive to solution pH under acidic conditions, indicating that the prepared fluorescent composite has potential application in acid microenvironment fluorescence detection.
研究领域:
材料科学
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光学
·
分析化学
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产品关联
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2024
·
IF 5.1
Bowen Wang,Xuyan Xue,Changshuai Gong,Xuejiao Wang,Qiushi Wang,Ji-Guang Li
A series of Tb 3+ substituted layered perovskite Sr(La 1- x Tb x )AlO 4 ( x = 0–1) was synthesized via solid-state reaction. The influence of Tb 3+ on the phase, structure, photoluminescence, and long afterglow properties of the SrLaAlO 4 product was investigated. The fully substituted product SrTbAlO 4 was found to be isostructural with its SrLaAlO 4 counterpart, and the crystal structure parameters were first reported in this work. Photoluminescence investigation found that benefiting from the unique layered crystal structure, the activator Tb 3+ was well separated and the optimal doping concentration was found to be as high as 20 at%. Except for photoluminescence, the products simultaneously show long afterglow properties due to disorder cations distribution in the local structure and thus induced defect condition. When the UV light source is turned off, the afterglow luminescence of SrLaAlO 4 : 0.03 Tb 3+ can last over 1 h. The trap distribution of SrLaAlO 4 : Tb 3+ was analyzed in detail by thermoluminescence. The trap depth is calculated to be around 0.7–0.81 eV, the value of which highly coincides with the ideal energy level for trapping and releasing electrons at room temperature. On the basis of the experimental results, the mechanism of long afterglow luminescence of SrLaAlO 4 : Tb 3+ is elaborated and discussed.
研究领域:
材料科学
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光学
✓ 已验证
DOI
高影响因子
OPTIK
·
2019
·
IF 1.914
Benze Wu,Jin Li,Qiang Li
The Mn-doped nano-ZnO powder was successfully synthesized via co-precipitation and vacuum annealing and the scanning electron microscopy (SEM), X-ray diffracton (XRD), ultraviolet visible absorption (Uv–vis) and photoluminescence (PL) of as-synthesized samples were characterized. The SEM and XRD show that the morphology of the synthesized samples was wurtzite nanosheets and nanoparticles at low doping concentration and with increasing Mn-doping concentration, mainly became to nanoparticle with a size of about 50nm. All of the ultraviolet absorption edges of Mn-doped ZnO have blue shift from Uiv-vis spectra and PL spectra show that Mn-doping significantly enhance the visible excitation band compared with pure ZnO, which indicates that Mn-doping not only produces elemental energy levels, but also affects the intrinsic defect energy levels of ZnO.
研究领域:
材料科学
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光学
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2023
·Vol. 52
·期 37
·13278-13289
·
IF 4
Chun Sun,Jiachen Han,Yiwei Zhao,Xiaohui Liu,Chao Fan,Kai Lian
Room temperature phosphorescence (RTP) materials are widely used in various fields. However, the realization of multicolor RTP via facile approaches still remains a great challenge. In this study, we propose an in situ hydrolysis method using different solvents to synthesize blue, green, and yellow phosphorescence ZnO/SiO2 composites. By investigating the photoluminescence (PL) and phosphorescence mechanisms of ZnO/SiO2 composites, it is discovered that the solvents not only introduce impurities to ZnO but also affect the position of defect energy levels, leading to the variation in luminescent performance. Meanwhile, the as-synthesized ZnO/SiO2 composites exhibit stable PL and phosphorescence under extreme conditions. Specifically, the PL and phosphorescence properties of the composites are well maintained at high temperature (523 K) or underwater. Owing to the multicolor phosphorescence properties of these ZnO/SiO2 products, herein, we demonstrate that ZnO/SiO2 composites can act as new smart materials for information encryption, fingerprint identification, and white light-emitting diodes (WLEDs).
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Light-Science & Applications
·
2024
·Vol. 13
·期 1
·1-15
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IF 20.6
Lv Xulong,Liang Yanjie,Zhang Yi,Chen Dongxun,Shan Xihui,Wang Xiao-Jun
Extensive research has been conducted on visible-light and longer-wavelength infrared-light storage phosphors, which are utilized as promising rewritable memory media for optical information storage applications in dark environments. However, storage phosphors emitting in the deep ultraviolet spectral region (200–300 nm) are relatively lacking. Here, we report an appealing deep-trap ultraviolet storage phosphor, ScBO 3 :Bi 3+ , which exhibits an ultra-narrowband light emission centered at 299 nm with a full width at half maximum (FWHM) of 0.21 eV and excellent X-ray energy storage capabilities. When persistently stimulated by longer-wavelength white/NIR light or heated at elevated temperatures, ScBO 3 :Bi 3+ phosphor exhibits intense and long-lasting ultraviolet luminescence due to the interplay between defect levels and external stimulus, while the natural decay in the dark at room temperature is extremely weak after X-ray irradiation. The impact of the spectral distribution and illuminance of ambient light and ambient temperature on ultraviolet light emission has been studied by comprehensive experimental and theoretical investigations, which elucidate that both O vacancy and Sc interstitial serve as deep electron traps for enhanced and prolonged ultraviolet luminescence upon continuous optical or thermal stimulation. Based on the unique spectral features and trap distribution in ScBO 3 :Bi 3+ phosphor, controllable optical information read-out is demonstrated via external light or heat manipulation, highlighting the great potential of ScBO 3 :Bi 3+ phosphor for advanced optical storage application in bright environments.
研究领域:
材料科学
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光学工程
·
物理学
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产品关联
DOI
PubMed
高影响因子
OPTICS EXPRESS
·
2022
·Vol. 30
·期 21
·37795-37814
·
IF 3.833
Chuansong Chen,Chuansong Chen,Wenjie Zhang,Wenjie Zhang,Pengyi Duan,Wenying Liu,Muhammad Shafi,Muhammad Shafi,Xiaoxuan Hu,Can Zhang,Chao Zhang,Baoyuan Man,Baoyuan Man,Mei Liu
Improving the photo-induced charge transfer (PICT) efficiency by adjusting the energy levels difference between adsorbed probe molecules and substrate materials is a key factor for boosting the surface enhanced Raman scattering (SERS) based on the chemical mechanism (CM). Herein, a new route to improve the SERS activity of two-dimensional (2D) selenium and tin compounds (SnSex, 1 ≤ x ≤ 2) by the hybrid phase materials is researched. The physical properties and the energy band structure of SnSex were analyzed. The enhanced SERS activity of 2D SnSex can be attribute to the coupling of the PICT resonance caused by the defect energy levels induced by Se vacancy and the molecular resonance Raman scattering (RRS). This established a relationship between the physical properties and SERS activity of 2D layered materials. The resonance probe molecule, rhodamine (R6G), which is used to detect the SERS performance of SnSex nanosheets. The enhancement factor (EF) of R6G on the optimized SnSe1.35 nanosheets can be as high as 2.6 × 106, with a detection limit of 10−10 M. The SERS result of the environmental pollution, thiram, shows that the SnSex nanosheets have a practical application in trace SERS detection, without the participation of metal particles. These results demonstrate that, through hybrid phase materials, the SERS sensitivity of 2D layered nanomaterials can be improved. It provides a kind of foreground non-metal SERS substrate in monitoring or detecting and provide a deep insight into the chemical SERS mechanism based on 2D layered materials.
研究领域:
材料科学
·
化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF LUMINESCENCE
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2023
·
IF 3.6
Xiaochun Hou,Chengxue Du,Qing Pang,Chaoyang Jia,Xiaojun Wang,Dangli Gao
Up-conversion persistent luminescence (UCPL) nanoparticles have captured tremendous attention due to their unique optical operating performance such as the absence of auto-fluorescence and the charging capacity of near-infrared (NIR) light. However, the weak afterglow intensity as well as low duration limits their practical applications including multimode anti-counterfeiting and biological imaging, etc. Herein, typical green persistent luminescence (PersL) and photo-stimulated luminescence (PSL) of Zn 2 GeO 4 :Mn 2+ phosphors were enhanced via non-equivalent Li + co-doping, in which the preferred site selection of Mn 2+ and Li + have been verified by using the first-principles theory. The possible luminescent enhancement mechanisms were proposed based on improving the oxygen vacancy density and promoting the formation of Mn 4+ defect energy level in bandgap structure by non-equivalent doping of Li + . Interestingly, UCPL of Zn 2 GeO 4 :Mn 2+ ,Li + can be achieved after charging of Vis to NIR light. It is worth noting that this UCPL can be further enhanced by the sensitization of NaYF 4 :Yb,Tm nanoparticles via simply mixing Zn 2 GeO 4 :Mn 2+ ,Li + and NaYF 4 :Yb,Tm under 980 laser stimulation. As a result, Zn 2 GeO 4 :Mn 2+ ,Li + phosphor exhibits the enhanced quintuple-mode luminescence including photoluminescence , PersL, PSL, photo-stimulated persistent luminescence and UCPL. In particular, the achieved NIR rechargeable UCPL hybrid phosphors exhibit enormous potential for higher order anti-counterfeiting and rewriteable data encryption and decryption applications.
研究领域:
材料科学
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光学工程
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Molecular Catalysis
·
2025
·
IF 4.9
Bo Jiang,Shu-Lin Liu,Zhe-Yan Jin,Zhao Wang,Bin-Can Cheng,Ze-Long Guan,Ying Hong,Zhao Wei,Zhi Qiao,Jian Tao,Bao-Lian Su
Selective hydrogenation driven by heat is a critical industrial process for purifying alkene feedstocks with serious problems of energy and H 2 consumption. Photochemistry-assisted strategy offers a sustainable alternative owing to its superiority of H 2 -free reaction under ambient temperature, unfortunately, with a challenging demand on efficient catalysts. Herein, a wide-spectrum-responsive Pd/N-TiO 2 photo-thermal catalyst was developed by a solvothermal method for photochemistry-assisted selective hydrogenation of butadiene in propene. It shows an excellent catalytic performance, with 100 % alkenes selectivity and 100 % butadiene conversion under irradiation of full-light (i.e., 320 nm∼780 nm). Notably, over 53 % butadiene conversion with 100 % alkenes selectivity was successfully retained on Pd/N-TiO 2 after shortening the wavelength range to visible light, much superior to that on Pd-TiO 2 (i.e., <1 % butadiene conversion). Further exploration reveals that the nitrogen doping extends the light-responsive wavelength of titanium oxide from ∼380 nm to above 500 nm owing to the formation of Ti 3+ and oxygen vacancies, which later create a defect energy level (i.e., ∼-0.53 to -0.12 eV) between the valence-conduction band of TiO 2 . The wide spectral response of N-TiO 2 enhances the water photolysis to produce intermediate hydrogen ([H]) that acts as the hydrogen source for the tandem butadiene hydrogenation over the Pd surface. The work indicates that developing a dual-functional catalyst with an expanded light-responsive wavelength is an efficient way to enhance the photochemistry-assisted selective hydrogenation.
研究领域:
化学工程
·
材料科学
·
催化化学
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）