APPLIED CATALYSIS B-ENVIRONMENTAL
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2019
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IF 14.229
Yawei Wang,Shunhang Wei,Xiaoxiang Xu
Solid solutions between SrTaO 2 N and CaTaO 2 N, i.e. Sr 1-x Ca x TaO 2 N (0.0 ≤ x ≤ 1.0) were synthesized and investigated as photocatalysts for water oxidation and reduction. A wealth of important parameters such as Ta-(O, N) bond length, Ta-(O, N)-Ta bond angle, band gap and band edge positions can be successively tuned by varying Sr/Ca molar ratios at A site. These solid solutions work well as photocatalysts to drive water splitting reactions under visible light illumination which clearly outperform their parent compounds SrTaO 2 N and CaTaO 2 N. Apparent quantum efficiency as high as 1.67% at 420 ± 20 nm was achieved on Sr 0.4 Ca 0.6 TaO 2 N (x = 0.6) which stands as the highest one reported for SrTaO 2 N and CaTaO 2 N to date. This simple approach by cation control at A site serves as a useful tool to tailor photocatalytic properties of perovskite oxynitrides, opening new playgrounds for the design and development of these tempting compounds as efficient photocatalysts.
研究领域:
材料科学
·
光催化化学
✓ 已验证
产品关联
DOI
高影响因子
ORGANIC ELECTRONICS
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2018
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IF 3.68
Xiao Gong,Wenwen Ma,Yunxia Li,Lingqi Zhong,Wenjing Li,Xiujian Zhao
Luminescent solar concentrators (LSCs) as alternatives to solar cells are suitable for photovoltaic windows. Generally semiconductor quantum dots are employed as emitters for LSC fabrication due to their advantages such as photostability, spectral tunability, and high photoluminescence quantum yield . In this paper, we used low cost and environmentally friendly N-doped carbon-dots (N-CDs) as phosphors to fabricate N-CDs/PMMA slab based luminescent solar concentrators. The high-performance N-CDs/PMMA slab based LSCs with an external optical efficiency of 12.23% could be achieved when the concentration of N-CDs within the PMMA matrix is 0.08 wt%. Our results showed that N-CDs/PMMA slab based luminescent solar concentrators make the practical use of LSCs more feasible because of the unique properties of N-CDs.
研究领域:
材料科学
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可再生能源
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2021
·
IF 13.273
Haojun Yu,Jian Chen,Ruiyu Mi,Juyu Yang,Yan-gai Liu
Broadband near-infrared light (NIR) near 800 nm has broad application prospects in food detection and night vision monitoring. Compared with NIR chips, NIR phosphors have distinct advantages, including low cost, a mature synthesis process, and tunable combination. However, at present, oxide NIR phosphors have some disadvantages, such as a narrow full width at half maximum (FWHM), poor thermal stability, and low photoelectric efficiency. Herein, K 3 ScF 6 :Cr 3+ NIR phosphors with a cubic structure were synthesized using the hydrothermal method. These phosphors can be effectively excited by blue light (430 nm) and red light (630 nm), leading to a broadband Cr 3+ emission from 650 nm to 950 nm with a large FWHM of 430 nm. They also exhibit excellent thermal stability and retain 87.3% of their initial intensity at 150 °C. Under a driving current of 100 mA, their photoelectric efficiency can reach 9.315% of that of fabricated NIR light-emitting diodes (NIR-LED). An NIR-LED device based on this phosphor can thus be implemented in night vision imaging systems.
研究领域:
材料科学
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光学工程
✓ 已验证
DOI
高影响因子
Materials Chemistry Frontiers
·
2021
·Vol. 5
·期 12
·4746-4755
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IF 6.482
Xiao Gong,Hang Jiang,Mengyan Cao,Zhihui Rao,Xiujian Zhao,Alberto Vomiero
Heavy-metal-free quantum dots (QDs) are promising luminophores for luminescent solar concentrators (LSCs) because of environmental friendliness, which is essential for industrial applications. In order to keep high optical quality and inhibit aggregation-induced quenching, usually QDs can only be loaded at low concentration in a polymer optical waveguide material for LSCs, which significantly impairs the power conversion efficiency (PCE). Thus, it is a challenge to fabricate high-performance LSCs with high QD loading. Here, dual emission Eu-doped ZnO QDs with strong solid-state fluorescence are synthesized via a simple sol–gel method, which enables two characteristic photoluminescence peaks at 551 nm and 614 nm. Furthermore, Eu-doped ZnO QDs with dual fluorescence emission are for the first time reported to be applied in LSCs. The performance of LSCs can be influenced by the loading concentration of Eu-doped ZnO QDs in polyvinyl pyrrolidone (PVP) films. The obtained external optical efficiency (ηopt) of the LSCs based on Eu-doped ZnO QDs can be relatively high (4.37%) compared to the reported LSCs with a similar area when the loading concentration of Eu-doped ZnO QDs is up to 13.2% because of both their high photoluminescence intensity and dual fluorescence emission. Our results demonstrate that dual emission Eu-doped ZnO QDs with strong solid-state fluorescence are promising candidates as luminophores for LSCs.
研究领域:
材料科学
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能源技术
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光学工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED MATERIALS
·
2023
·Vol. 35
·期 41
·2306517
·
IF 29.4
Wenge Xiao,Endale T. Basore,Guojun Zheng,Xiaofeng Liu,Beibei Xu,Jianrong Qiu
The brightness of doped luminescent materials is usually limited by the ubiquitous concentration quenching phenomenon resulting in an intractable tradeoff between internal quantum efficiency and excitation efficiency. Here, an intrinsic suppression of concentration quenching in sensitized luminescent systems, by exploiting the competitive relationship between light emitters and quenchers in trapping excitation energies from sensitizers, is reported. Although Cr 3+ sensitizers and trivalent lanthanide (Ln 3+ , Ln = Yb, Nd, and Er) emitters themselves are highly susceptible to concentration quenching, the unprecedentedly high-brightness luminescence of Cr 3+ –Ln 3+ systems is demonstrated in the short-wave infrared (SWIR) range employing high concentrations of Cr 3+ , whereby a record photoelectric efficiency of 23% is achieved for SWIR phosphor-converted light-emitting diodes, which is about twice as high as those previously reported. The results underscore the beneficial role of emitters in terminating excitation energies, opening up a new dimension for developing efficient sensitized luminescent materials.
研究领域:
材料科学
·
光学
·
光子学
✓ 已验证
DOI
高影响因子
OPTICAL MATERIALS
·
2024
·
IF 3.8
Wenbin Lin,Yi Xu,Jiyou Zhong
Near-infrared (NIR) phosphor-converted light-emitting diode (pc-LED) has been considered as a smart light source for NIR spectroscopy applications, leading to a growing need of developing broadband NIR phosphors. Herein, a new composition Zn 4 InSbO 8 :Cr 3+ phosphor with classical spinel-type structure was synthesized, which emits a broadband NIR light covering a region of 700–1200 nm with a peak centered at 860 nm under 460 nm excitation. The sample with an optimized Cr 3+ concentration possesses a full width at half maximum (FWHM) as broad as 180 nm mainly ascribing to multi crystallographic sites occupation. Moreover, the absorption efficiency (AE), internal quantum efficiency (IQE) and thermal stability were investigated to estimate the practicality. The relatively long-wavelength NIR emission produced by Cr 3+ in this spinel make it suitable for multi-functional applications. Finally, the asprepared phosphor combining with blue LED chip is used to fabricate a prototype NIR pc-LED, giving a NIR output power of 4.8 mW under 100 mA forward bias current with a photoelectric efficiency of 1.63%, showcasing the potential use of this material as a luminescent converter in the application of NIR pc-LEDs.
研究领域:
材料科学
·
光电子学
·
光子学
✓ 已验证
DOI
高影响因子
Journal of Materials Chemistry C
·
2023
·Vol. 11
·期 42
·14787-14795
·
IF 6.4
Zhibin Chen,Lehui Liu,Feifei Yuan,Yisheng Huang,Lizhen Zhang,Zhoubin Lin
Near-infrared (NIR) emission materials have been widely used in food inspection, spectral analysis, and so on. The broader the emission band of NIR phosphors, the more the components will be detected, making the search for broadband NIR phosphors still under demand. Herein, a broadband NIR phosphor with a FWHM of 259 nm is obtained by adjusting the synthesis temperature, due to the intrinsic advantages of phase transition and microstructure diversity in the Mg2Al4Si5O18 compound. As the sintering temperature increases from 1400 °C to 1460 °C, the partial Mg2Al4Si5O18:Cr3+ sample is transformed from the low temperature phase to the high temperature phase with a broadening of the emission FWHM from 25 nm to 259 nm, which can be attributed to the longer Mg–O bond and the larger volume of the [MgO6] octahedron causing a weaker crystal field after the phase transition. A series of phosphors with different Cr3+ doping concentrations are synthesized at the optimum synthesis temperature of 1450 °C and their properties are studied in detail. The luminescence of Mg2Al4Si5O18:0.005Cr3+ decreases with the increasing temperature, and about 56% is maintained at about 150 °C and the emission peak width still remains at 251 nm. NIR phosphor-converted LEDs (pc-LEDs) with an output power of 6.82 mW and a photoelectric efficiency of 3.82% are achieved. This work provides fresh insight into the exploration of novel Cr3+ ion-based broadband NIR materials for pc-LEDs.
研究领域:
材料科学
·
光学
·
光子学
·
半导体器件
✓ 已验证
DOI
高影响因子
Journal of Physical Chemistry Letters
·
2024
·
IF 4.8
Hongyan Yin,Can Zhang,Quanzhen Zhang,Pu Wang,Jianguo Tang,Sui Mao
Metallic nanoparticles can generate photoexcited hot carriers on the femtosecond scale under light excitation, which holds immense significance for applications such as optical communication and ultrafast imaging. In this study, a tunnelling junction structure with ZrO2 as the dielectric layer is designed and fabricated to achieve efficient hot hole collection between Au nanoparticles and P-type Si. Through characterizations of photoconductive atomic force microscopy, the electrical transition from an ohmic contact to a tunneling junction is confirmed, and the transfer pathway of Au hot holes to P-type Si upon 520 nm excitation is clearly observed. The impact of the tunneling structure on device performance is investigated through the fabrication of Si/ZrO2/Au/TiO2 photodiodes. The performance tests show that hot hole collection by the tunneling effect significantly enhances a range of parameters, e.g., external quantum efficiency by 250%. Noticeably, the external quantum efficiency attributed to photogenerated hot carriers under 520 nm excitation is estimated to exceed 2.5%. Moreover, the transient photoresponse of the photodiodes is examined with a typical rising time of less than 20 ns.
研究领域:
光电子学
·
纳米光子学
·
固态物理
·
材料科学
·
半导体器件
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）