JOURNAL OF ALLOYS AND COMPOUNDS
·
2016
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IF 3.014
Dongchen Che,Di Ding,Hongzhi Wang,Qinghong Zhang,Yaogang Li
Efficient aqueous synthetic methods for near-infrared quantum dots as bioimaging agents are urgently required. In this work, a simple and fast synthesis of highly luminescent, near-infrared Ag 2 Se quantum dots (QDs) in aqueous media is reported. The method avoids high temperature, pressure and organic solvents to directly generate water-dispersible Ag 2 Se QDs. The photoluminescence emission of Ag 2 Se QDs ranges from 835 to 940 nm by different Ag:Se molar ratio. Using the ZnSe as a shell, the quantum yield reaches up to 42%. The Ag 2 Se ZnSe QDs with high quantum yield, near-infrared and low cytotoxic could be used as good cell labels, showing great potential applications in bio-imaging.
研究领域:
材料科学
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生物医学工程
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
OPTICS EXPRESS
·
2024
·Vol. 32
·期 22
·37984-37993
·
IF 3.2
Linfeng Wang,Xiaoyue Huang,Tingting Zhang,Jinke Bai,Ting Zhao,Bing Xu,Qinghua Li,Xiao Jin,Xiao Jin,Yuxiao Wang,Xueru Zhang,Yinglin Song,Yinglin Song
InP quantum dots (QDs) have emerged as promising nanomaterials in various fields due to their exceptional optical properties. However, its wide emission linewidth limits further application. In this study, we synthesized high-quality InP/ZnSe/ZnS QDs by suppressing hole defects. The unreacted In precursors during nucleation easily enter ZnSe in the subsequent shelling process, forming a hole trapping center that adversely affects the photo-excitons radiative recombination. Our results demonstrate that the presence of In ions in ZnSe shell enhances exciton-phonon coupling, broadens the fluorescence emission spectrum, and weakens exciton binding energy. The optimized InP QDs exhibit a line width of 44 nm and 90% PLQY at 630 nm. Furthermore, our investigation into the interaction between shell hole defects and core exciton function provides valuable insights for designing and preparing another high-performance core-shell heterojunction QDs.
研究领域:
纳米技术
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材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2021
·
IF 8.128
Jinxin Wei,Zhe Hu,Wenjie Zhou,Yi Qiu,Hanqing Dai,Yuanyuan Chen,Zhongjie Cui,Siyu Liu,Haiyang He,Wanlu Zhang,Fengxian Xie,Ruiqian Guo
With the blooming development of zero-dimensional nanomaterials , I-III-VI alloying quantum dots (QDs) with outstanding photoelectrical properties have emerged to attract much attention as promising environmentally-friendly substitutions for conventional binary Cd-based QDs. In this work, a facile one-pot method was introduced to synthesize unreported quaternary Ag-Cu-Ga-Se/ZnSe (ACGSe/ZnSe) QDs. A relatively high photoluminescence quantum yield (PL QY) of 71.9% and a tunable emission from 510 to 620 nm were successfully achieved. We explored the roles of alloying compositions in ACGSe/ZnSe QDs, inferring that increased Ag proportion would not only lower the V defect level which leads to the blue shift of emission, but also slow the ZnSe shelling process owing to the larger lattice distortion. At last, the white light-emitting diodes (WLEDs) were fabricated with ACGSe/ZnSe QDs as the conversion layer, indicating that the as-prepared QDs are a promising candidate for further applications.
研究领域:
材料科学
·
纳米技术
·
光电技术
✓ 已验证
产品关联
DOI
PubMed
高影响因子
JOURNAL OF COLLOID AND INTERFACE SCIENCE
·
2022
·
IF 9.965
Linfeng Wang,Jinke Bai,Tingting Zhang,Xiaoyue Huang,Tianyi Hou,Bing Xu,Dongyu Li,Qinghua Li,Xiao Jin,Yuxiao Wang,Xueru Zhang,Yinglin Song
The emission linewidth of quantum dots (QDs) is one of the important optical properties, which is essential for the applications of QD lasers, high-quality displays, and biological imaging. However, we know less about controlling emission linewidth and its underlying mechanisms. Here we introduce a wurtzite ZnSe shell onto a wurtzite CdSe core to produce asymmetric strain due to their large, anisotropic lattice mismatch. Such asymmetric pressure induces significant splitting (Δ AB ) between heavy-hole (hh) and light-hole (lh) in valence band (VB). We show that the emission intensity from the lh state (E lh ) is significantly suppressed with the increasing Δ AB caused by the strong asymmetric strain. We demonstrate that the exciton-phonon coupling (EPC) is greatly inhibited under the anisotropic lattice strain. The alloying process between the core and shell occurs under the strong lattice strain and raises the longitudinal-optical (LO) phonon energy (E LO ). Higher LO phonon energy declines LO phonon occupation numbers (N LO ) and synergistically reduces the EPC. The asymmetrically strained alloy QDs ensemble exhibits highly bright emission with ultra-narrow linewidths of 13.8 nm (∼520 nm) and 15.8 nm (∼620 nm). This concept of band structure regulation via asymmetric strain can provide a new platform for high-quality QDs beyond the currently achieved.
研究领域:
材料科学
·
光电子学
·
半导体物理
✓ 已验证
产品关联
DOI
PubMed
高影响因子
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