OPTICAL MATERIALS
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2023
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IF 3.9
Qiaocan Huang,Zunxian Yang,Yuanqing Zhou,Yuliang Ye,Bingqing Ye,Zihong Shen,Wenbo Wu,Zongyi Meng,Zhiwei Zeng,Hongyi Hong,Songwei Ye,Zhiming Cheng,Qianting Lan,Jiaxiang Wang,Ye Chen,Hui Zhang,Tailiang Guo,Fushan Li,Yongyi Chen,Zhenzhen Weng
Quantum dots (QDs) with an alloy shell (CdSe@ZnS/ZnS) are one of the most promising emitters for optoelectronic devices for their superior properties such as narrow full width at half maximum (FWHM), high color purity and tunable wavelength. However, the presence of lattice stresses during the internal growth of quantum dots can cause severe exciton bursts. Optimizing the ramp-up process during the core growth of quantum dots and rising the temperature when cladding with ZnS shells is an effective strategy for obtaining high-quality quantum dots. Besides, the stability of quantum dots is further modified by using 1-Octanethiol (OT) as ligands. Detailed analyses of the morphology, colloidal stability, and luminescence performance of QDs were represented. Finally, green CdSe@ZnS/ZnS QLEDs with prolonged carrier lifetimes and less defect state densities achieved peak luminescence at 361850 cd/m 2 with a current efficiency (CE) of 33 cd/A. This work provides a better understanding of the relationship between defect state density and the performance of quantum dots for designing and fabricating high-performance light-emitting diodes.
研究领域:
材料科学
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光学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
Light-Science & Applications
·
2022
·Vol. 11
·期 1
·1-10
·
IF 20.257
Yu Peng,Cao Sheng,Shan Yuliang,Bi Yuhe,Hu Yaqi,Zeng Ruosheng,Zou Bingsuo,Wang Yunjun,Zhao Jialong
InP-based quantum dot light-emitting diodes (QLEDs), as less toxic than Cd-free and Pb-free optoelectronic devices, have become the most promising benign alternatives for the next generation lighting and display. However, the development of green-emitting InP-based QLEDs still remains a great challenge to the environmental preparation of InP quantum dots (QDs) and superior device performance. Herein, we reported the highly efficient green-emitting InP-based QLEDs regulated by the inner alloyed shell components. Based on the environmental phosphorus tris(dimethylamino)phosphine ((DMA) 3 P), we obtained highly efficient InP-based QDs with the narrowest full width at half maximum (~35 nm) and highest quantum yield (~97%) by inserting the gradient inner shell layer ZnSe x S 1−x without further post-treatment. More importantly, we concretely discussed the effect and physical mechanism of ZnSe x S 1– x layer on the performance of QDs and QLEDs through the characterization of structure, luminescence, femtosecond transient absorption, and ultraviolet photoelectron spectroscopy. We demonstrated that the insert inner alloyed shell ZnSe x S 1− x provided bifunctionality, which diminished the interface defects upon balancing the lattice mismatch and tailored the energy levels of InP-based QDs which could promote the balanced carrier injection. The resulting QLEDs applying the InP/ZnSe 0.7 S 0.3 /ZnS QDs as an emitter layer exhibited a maximum external quantum efficiency of 15.2% with the electroluminescence peak of 532 nm, which was almost the highest record of InP-based pure green-emitting QLEDs. These results demonstrated the applicability and processability of inner shell component engineering in the preparation of high-quality InP-based QLEDs.
研究领域:
材料科学
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光电子学
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纳米技术
✓ 已验证
DOI
高影响因子
RSC Advances
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2020
·Vol. 10
·期 38
·22616-22621
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IF 3.119
Liren Wang,Han Wang,Yanming Liu,Xinyu Wang,Peng Tao,Wen Shang,Benwei Fu,Chengyi Song,Tao Deng
This paper introduces an approach to synthesize bimetallic nanoparticles under an alternating temperature field in aqueous solution. During the synthesis, pyro-catalytic barium titanate is used as the substrate to reduce the metallic ions dispersed in the solution due to the generated charges at the surface of pyro-materials under temperature oscillation. Chloroauric acid and potassium tetrachloroplatinate are used as precursors to produce gold/platinum bimetallic nanoparticles through a pyro-catalytic process. Transmission electron microscopy characterization, in combination with energy dispersive X-ray spectroscopy mapping, demonstrates that the bimetallic nanoparticle is composed of an Au core and Au/Pt alloy shell structure. Compared to the conventional approaches, the pyroelectric synthesis approach demonstrated in this work requires no toxic reducing agents and waste heat can be used as a thermal energy source in the synthesis. Hence, it offers a potential “green” synthetic method for bimetallic nanoparticles.
研究领域:
材料科学
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纳米技术
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催化化学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
APPLIED CATALYSIS B-ENVIRONMENTAL
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2015
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IF 7.435
Zhi Liang Zhao,Lian Ying Zhang,Shu Juan Bao,Chang Ming Li
Metal core–shell nanostructures have been extensively studied as one of the most promising electrocatalysts to significantly reduce the loading of the expensive Pt catalyst for fuel cells but it is very challenging to fabricate such a structure to possess proper metal components while making small and uniformly distributed nanoparticles for high catalytic performance. In this work, small and uniformly distributed Au-core/PtCu alloy–shell structured nanoparticles (Au@PtCu NPs) were fabricated by a novel one-pot facile method. The as-prepared Au@PtCu/C has a much larger electrochemical active surface area (ECSA) (64.8 m 2 g −1 Pt ) than that of AuPtCu/C(38.5 m 2 g −1 Pt ), PtCu/C (31.02 m 2 g −1 Pt ) and commercial Pt/C (25.4 m 2 g −1 Pt ) catalyst. This new catalyst not only greatly reduces Pt loading but also significantly increases the catalytic activity and stability toward methanol oxidation reaction in comparison to the commercial electrocatalyst. This is mainly attributed to a synergistic effect from the small and uniform core–shell nanostructure and the unique chemical compositions of Au and PtCu alloy, thus offering a great potential for a less expensive but highly active catalyst toward direct methanol fuel cells (DMFCs).
研究领域:
材料科学
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能源科学
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催化化学
✓ 已验证
产品关联
DOI
高影响因子
Journal of Energy Chemistry
·
2021
·
IF 9.676
Qi Xue,Xin-Yu Bai,Yue Zhao,Ya-Nan Li,Tian-Jiao Wang,Hui-Ying Sun,Fu-Min Li,Pei Chen,Pujun Jin,Shi-Bin Yin,Yu Chen
Inefficient electrocatalysts and high-power consumption are two thorny problems for electrochemical hydrogen (H 2 ) production from acidic water electrolysis. Herein we report the one-pot precise synthesis of ultrafine Au core-PtAu alloy shell nanowires (Au@Pt x Au UFNWs). Among them, Au@Pt 0.077 Au UFNWs exhibit the best performance for formic acid oxidation reaction (FAOR) and hydrogen evolution reaction (HER), which only require applied potentials of 0.29 V and −22.6 mV to achieve a current density of 10 mA cm −2 , respectively. The corresponding formic acid electrolyzer realizes the electrochemical H 2 production at a voltage of only 0.51 V with 10 mA cm −2 current density. Density functional theory (DFT) calculations reveal that the Au-riched PtAu alloy structure can facilitates the direct oxidation pathway of FAOR and consequently elevates the FAOR activity of Au@Pt 0.077 Au UFNWs. This work provides meaningful insights into the electrochemical H 2 production from both the construction of advanced bifunctional electrocatalysts and the replacement of OER.
研究领域:
材料科学
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电化学
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能源科学
✓ 已验证
产品关联
DOI
高影响因子
Materials Today Physics
·
2023
·
IF 11.5
Qi Xue,Zixin Ge,Zihan Yuan,Jiangtao Huang,Bin He,Yu Chen
The highly active, selective and stable anode electrocatalysts for the ethanol oxidation reaction (EOR) are extremely desirable for the application of direct ethanol fuel cells (DEFCs). Herein, one-dimensional Au core@AuPt 0·20 Rh 0.08 alloy shell nanowires (Au@AuPt 0·20 Rh 0.08 CS-NWs) with long aspect ratio and cross-linked network architecture are synthesized. For the EOR, Au@AuPt 0·20 Rh 0.08 CS-NWs display higher peak current density, better resistance to CO poisoning and more lasting stability compared with Au@AuPt 0.28 CS-NWs and commercial Pt black electrocatalyst, which can be attributed to the trimetallic synergistic effect between the Au, Pt and Rh atoms. Specifically, the Rh can promote the C–C bonds and adsorb OH ads while Au can change the electronic structure of Pt, endowing Pt with a high anti-poisoning ability to CO ads and promoting the complete oxidation of various C1 intermediate to CO 2 . This work provides an effective strategy for the rational construction of high-performance Pt-based EOR electrocatalysts by optimizing composition, morphology and architecture.
研究领域:
材料科学
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电化学
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纳米技术
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能源材料
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Qi Zhang,Tian-Song Deng,Yun-Qi Dou,Ming-Zhang Wei,Shiqi Li,Jia Liu,Zhiqun Cheng
The localized surface plasmon resonances (LSPRs) in plasmonic nanoparticles have been used in accelerating photocatalytic reactions under light illumination. To improve the catalytic performance, bimetallic nanoparticles composed of a plasmonic core and a catalytic shell, where LSPR-excited hot electrons and the intrinsic catalytic active sites work synergistically, have attracted much attention. Despite progress in designing bimetallic catalysts, balancing the strong LSPR and catalytic sites remains challenging. Here, a trimetallic nanostructure containing a gold nanorod (AuNR) core and a silver–platinum (AgPt) hollow alloy shell was designed and used as a plasmon-mediated photocatalyst for methylene blue reduction reaction. Specifically, the AuNRs covered by a thin layer of Ag (Au@Ag) were used as the template to deposit Pt, forming a Au@AgPt trimetallic nanostructure. By changing the Ag and/or Pt precursor concentration, the external layer could be varied from AgPt heterostructure and AgPt hollow alloy shell to AuAgPt alloy dendrites. Using methylene blue as a model system, the photocatalytic reduction reaction was studied by adding the obtained nanoparticles as catalysts under visible and near-infrared light irradiation. The optimal photocatalytic performance of the trimetallic nanoparticles was seen with the AgPt hollow alloy shell, and the reaction rate is ∼7 times higher than that of the reaction without catalysts and ∼3 times higher than that of monometallic AuNRs, bimetallic Au@Ag, and Au@Pt nanorods. Plasmon energy transfer from the AuNRs to the AgPt layer, which enhances the charge-carrier generation, is responsible for outstanding photocatalytic performance. The approach used here to synthesize Au@AgPt trimetallic nanostructures is suitable for the design of other multimetallic photocatalysts.
研究领域:
材料科学
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纳米技术
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催化
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光子学
✓ 已验证
产品关联
DOI
高影响因子
ENVIRONMENTAL SCIENCE & TECHNOLOGY
·
2024
·
IF 10.8
Lihang Ma,Yi-bo Hu,Shuhan Li,Ting Du,Xinran Xiong,Yuanhuan Wu,Xiao-yan Li,Ming-Lai Fu,Baoling Yuan
Nanoscale zerovalent iron synthesized using borohydride (B-NZVI) has been widely applied in environmental remediation in recent decades. However, the contribution of boron in enhancing the inherent reactivity of B-NZVI and its effectiveness in removing hexavalent chromium [Cr(VI)] have not been well recognized and quantified. To the best of our knowledge, herein, a core–shell structure of B-NZVI featuring an Fe–B alloy shell beneath the iron oxide shell is demonstrated for the first time. Alloyed boron can reduce H+, contributing to more than 35.6% of H2 generation during acid digestion of B-NZVIs. In addition, alloyed B provides electrons for Fe3+ reduction during Cr(VI) removal, preventing in situ passivation of the reactive particle surface. Meanwhile, the amorphous oxide shell of B-NZVI exhibits an increased defect density, promoting the release of Fe2+ outside the shell to reduce Cr(VI), forming layer-structured precipitates and intense Fe–O bonds. Consequently, the surface-area-normalized capacity and surface reaction rate of B-NZVI are 6.5 and 6.9 times higher than those of crystalline NZVI, respectively. This study reveals the importance of alloyed B in Cr(VI) removal using B-NZVI and presents a comprehensive approach for investigating electron pathways and mechanisms involved in B-NZVIs for contaminant removal.
研究领域:
环境科学
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材料科学
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化学工程
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环境修复
✓ 已验证
产品关联
DOI
PubMed
高影响因子
ACS Applied Nano Materials
·
2024
·
IF 5.3
Er-Ji Zhang,Tian-Song Deng,Yu-Chun Cheng,Li-Yong Liu,Jia-Fei Gao,Jiahong Wen,Xiaoyu Zhao,Jie Liu
Plasmonic multimetal materials, consisting of a plasmonic core and a catalytic shell in a core–shell structure, often exhibit excellent catalytic performances. Such excellent performances arise from the synergistic collaboration between the plasmonic core’s localized surface plasmon-excited hot electrons and the catalytically active sites of the catalytic shell. In this context, a trimetallic nanostructure was designed featuring gold nanobipyramids (AuNBP) with a silver–platinum alloy shell, serving as a plasmon-mediated photocatalyst for the degradation of methyl orange (MO) under visible and near-infrared light. By altering the concentrations of the surfactants hexadecyltrimethylammonium bromide (CTAB) and hexadecyltrimethylammonium chloride (CTAC), the resulting nanostructure can take on either island-like or shell-like morphology. In the model system of the photocatalytic reaction of MO, employing the synthesized nanoparticles as catalysts, the study investigated the reaction under xenon lamp illumination. The trimetallic nanostructure exhibited robust photocatalytic performances, surpassing AuNBP by a factor of 27.8. The transfer of plasmon resonance energy from AuNBP to the silver–platinum alloy layer, augmenting the generation of charge carriers, elucidates its outstanding photocatalytic performance. The obtained trimetallic nanostructure showcases promising potential applications in the realm of photocatalysis, contributing to the development of advanced plasmon-enhanced photocatalysts with enhanced efficiency and multifunctionality.
研究领域:
纳米技术
·
催化
·
材料科学
·
环境科学
·
光学
✓ 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）