BIOMATERIALS
·
2013
·
IF 7.604
Ke Ding,Lihong Jing,Chunyan Liu,Yi Hou,Mingyuan Gao
Magnetically engineered Cd-free CuInS 2 @ZnS:Mn quantum dots (QDs) were designed, synthesized, and evaluated as potential dual-modality probes for fluorescence and magnetic resonance imaging (MRI) of tumors in vivo . The synthesis of Mn-doped core–shell structured CuInS 2 @ZnS mainly comprised three steps, i.e., the preparation of fluorescent CuInS 2 seeds, the particle surface coating of ZnS, and the Mn-doping of the ZnS shells. Systematic spectroscopy studies were carried out to illustrate the impacts of ZnS coating and the following Mn-doping on the optical properties of the QDs. In combination with conventional fluorescence, fluorescence excitation, and time-resolved fluorescence measurements, the structure of CuInS 2 @ZnS:Mn QDs prepared under optimized conditions presented a Zn gradient CuInS 2 core and a ZnS outer shell, while Mn ions were mainly located in the ZnS shell, which well balanced the optical and magnetic properties of the resultant QDs. For the following in vivo imaging experiments, the hydrophobic CuInS 2 @ZnS:Mn QDs were transferred into water upon ligand exchange reactions by replacing the 1-dodecanethiol ligand with dihydrolipoic acid-poly(ethylene glycol) (DHLA-PEG) ligand. The MTT assays based on HeLa cells were carried out to evaluate the cytotoxicity of the current Cd-free CuInS 2 @ZnS:Mn QDs for comparing with that of water soluble CdTe QDs. Further in vivo fluorescence and MR imaging experiments suggested that the PEGylated CuInS 2 @ZnS:Mn QDs could well target both subcutaneous and intraperitoneal tumors in vivo .
研究领域:
生物医学工程
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材料科学
·
影像学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA
·
2018
·
IF 1.795
Qiu-hang CHEN,Shi-liang MEI,Wu YANG,Wan-lu ZHANG,Gui-lin ZHANG,Jia-tao ZHU,Rui-qian GUO
Color tunable quantum dots (QDs) based on the Cu, Mn, Ag co-doped ZnInS core and ZnS outer-shell were synthesized by using an eco-friendly method. Core-shell doped QDs with the average size of 3.85 nm were obtained by using a one-pot synthesis followed by a hot injection with n -dodecanethiol (DDT) and oleylamine (OLA) as stabilizers in oil phase. Cu, Mn and Ag ions were introduced as single-dopant or co-dopants during the synthesis, providing an effective means to control the emission color of the QDs. The as-synthesized QDs showed photoluminescence emission ranging from green (530 nm) to near-red (613 nm), adjusted by doping components, dopant concentration, and Zn/In ratio. Importantly, quasi-white emission has been achieved by controlling the concentration of co-doped metal ions (Mn, Cu and Ag). The primary results demonstrated the promising potential of co-doped QDs as alternative materials for future high quality white LED applications.
研究领域:
材料科学
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
·
2018
·
IF 6.14
Ying-Chu Chen,Hao-Hsuan Chang,Yu-Kuei Hsu
Decoration of CuInS2 (CIS) quantum dots (QDs) on ZnO nanowires (NWs) with an interlayer of In2S3 as photoelectrode has been successfully fabricated on FTO via the simple solution routes for photoelectrochemical (PEC) application. Scanning electron microscopy, transmission electron microscopy, and X-ray diffraction are utilized to systematically analyze the morphology and structure of the CIS QD/In2S3/ZnO NWs heterostructure. The composition of this multilayer heterostructure and the removal of QD ligands by a thermal process are confirmed by X-ray photoelectron spectra. In comparison with CIS QDs/ZnO NWs, the CIS QD/In2S3/ZnO heterostructural photoelectrode displays an efficient charge separation and carrier transport path for photocurrent up to 2.4 mA·cm–2 that is competitive with other Cd- and Pb-free QD-based materials. In addition, Mott–Schottky analysis demonstrates the negative shift of the flat band in the CIS QD/In2S3/ZnO, which benefits the early onset potential. Significantly, this hierarchical photoelectrode shows the improvement the absorption and conversion of solar light in the visible region obtained using a pristine ZnO structure. Our research paves the way for exploring lead-free and lead-free sulfide materials in the new category of solar applications.
研究领域:
材料科学
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太阳能技术
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纳米科技
✓ 已验证
产品关联
DOI
高影响因子
Journal of Materials Chemistry C
·
2019
·Vol. 7
·期 24
·7279-7287
·
IF 6.641
Tong Yan,Yunyan Li,Xiaoxiao Song,Jie Wang,Zhuoying Xie,Dawei Deng
The cytotoxicities of the elements of current quantum dots (QDs) greatly restrict their applications in biomedical fields. Herein, we firstly proposed and synthesized oil-soluble heavier-element-free (or Cd-free) CuFeS2/ZnS QDs, and focused on the synthetic controls over the core/shell structure. It was found that although the as-prepared CuFeS2 QDs are nonemissive, the in situ ZnS-overcoating could make them exhibit bright near-infrared (NIR) photoluminescence (PL) (PL peak at 840 nm; PL quantum yield (QY) up to 52%). We also analyzed their shape, structure and elemental composition in detail. Next, by the interaction between oil-soluble QDs and liposomes, the aqueous QD-laden liposomes (named as LipQDs) were fabricated, allowing further exploration of bio-application. Finally, after further decorating with isolated macrophage membrane, the resulting LipQDs@M nanocomposites were observed to target actively postoperative tumor inflamed tissue (or other inflamed tissues), using an in vivo small animal IR optical imaging system. Our results indicate that these NIR-emitting CuFeS2/ZnS QDs should be a new promising fluorescent marker for biomedical optical imaging, as an alternative for Cd-, Hg-, and Pb-based ones.
研究领域:
生物医学工程
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材料科学
·
光学成像
✓ 已验证
产品关联
DOI
高影响因子
Laser & Photonics Reviews
·
2023
·Vol. 17
·期 5
·2200749
·
IF 11
Jinxing Zhao,Lijin Wang,Peiwen Lv,Fenghe Wang,Xu Li,Song Chen,Lei Qian,Aiwei Tang
Although cadmium (Cd)-based nanocrystals have enabled high-performance quantum-dot light-emitting diodes (QLEDs), their mass production is likely to be affected by environmental protection policies. Among all the potential Cd-free candidates, Cu-In-Zn-S (CIZS) nanocrystals (NCs) have attracted particular interests. Still, the performance of the corresponding LED is currently limited by imbalanced charge injection and luminescence quenching, which are both related to the ZnO-based electron transporting layer (ETL). This work demonstrates that ZnO nanoparticles (NPs) doped with Sn, Mg (Zn 1− x − y Sn x Mg y O), and passivated with Cl are promising to resolve the above issues. All-solution-processed QLEDs based on Cd-free CIZS NCs are fabricated by using Zn 0.9 Sn 0.1 O NPs as the ETL, and the peak external quantum efficiency (EQE max ) was nearly twice that of ZnO (EQE max = 1.74%). The main reason is that the incorporation of Sn can reduce the conductivity of ZnO by an order of magnitude. Combining the advantages of Zn 0.9 Sn 0.1 O, Zn 0.8 Sn 0.1 Mg 0.1 O@Cl NPs are designed by the co-doping of Mg and Cl passivation. The EQE max and current efficiency based on Zn 0.8 Sn 0.1 Mg 0.1 O and Zn 0.8 Sn 0.1 Mg 0.1 O@Cl as ETLs are further increased to 4.84%, 14.00 cd A −1 and 5.53%, 15.99 cd A −1 , respectively. The positive effects of Mg ions can remarkably optimize energy level structure to balance charge injection, while Cl can further passivate defects. The findings offer a new guideline for developing Cd-free light-emitting diodes.
研究领域:
材料科学
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光电技术
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纳米技术
✓ 已验证
产品关联
DOI
高影响因子
DALTON TRANSACTIONS
·
2015
·Vol. 44
·期 47
·20763-20768
·
IF 4.197
Lan Wang,Xiaojiao Kang,Lijian Huang,Daocheng Pan
We reported temperature-dependent photoluminescence (PL) studies on Cu–Zn–In–S quantum dot (QD) thin films. In this paper, cadmium-free and luminescent Cu–Zn–In–S quantum dot thin films were in situ formed by thermal decomposition of molecular-based precursors in the open air, without need of the complicated quantum dot synthesis. Molecular-based precursor solutions were prepared by dissolving Cu2O, ZnO, and In(OH)3 in the ethanol solution of butylamine and carbon disulfide. The effects of sintering temperature, sintering time, and the concentration of capping agents on the photoluminescence properties of Cu–Zn–In–S QD thin films have been systematically investigated. It was found that alkali metal ions play an important role in enhancing the PL quantum yield of quantum dot thin films. The as-prepared QD thin films show composition-tunable emission in the range of 535 nm to 677 nm, and the absolute PL quantum yields can reach as high as 22.1%. All of the as-deposited QD thin films show a single-exponential decay to temperature, indicating that these cadmium-free QD thin films have high potential as temperature probes.
研究领域:
材料科学
·
光学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Materials
·
2023
·Vol. 16
·期 7
·2869
·
IF 3.4
Quanzhen Sun,Jianlong Tang,Caixia Zhang,Yaling Li,Weihao Xie,Hui Deng,Qiao Zheng,Jionghua Wu,Shuying Cheng
Flexible CZTSSe solar cells have attracted much attention due to their earth-abundant elements, high stability, and wide application prospects. However, the environmental problems caused by the high toxicity of the Cd in the buffer layers restrict the development of flexible CZTSSe solar cells. Herein, we develop a Cd-free flexible CZTSSe/ZnO solar cell. The influences of the ZnO films on device performances are investigated. The light absorption capacity of flexible CZTSSe solar cells is enhanced due to the removal of the CdS layer. The optimal thickness of the ZnO buffer layers and the appropriate annealing temperature of the CZTSSe/ZnO are 100 nm and 200 °C. Ultimately, the optimum flexible CZTSSe/ZnO device achieves an efficiency of 5.0%, which is the highest efficiency for flexible CZTSSe/ZnO solar cells. The systematic characterizations indicate that the flexible CZTSSe/ZnO solar cells based on the optimal conditions achieved quality heterojunction, low defect density and better charge transfer capability. This work provides a new strategy for the development of the environmentally friendly and low-cost flexible CZTSSe solar cells.Keywords:Cd-free flexible CZTSSe/ZnO solar cells;ZnO buffer layer;CZTSSe/ZnO heterojunction;buffer layer optimization
研究领域:
材料科学
·
太阳能
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
Journal of Materials Chemistry C
·
2015
·Vol. 3
·期 39
·10114-10120
·
IF 4.696
Zhenyang Liu,Aiwei Tang,Miao Wang,Chunhe Yang,Feng Teng
A simple heating-up colloidal approach has been developed to synthesize quaternary Cu–In–Zn–S (CIZS) nanocystals with different emission colors, which can be tuned by varying the Cu : In : Zn precursor ratios. The as-obtained products have a quasi-triangular shape with a small size distribution, and their crystal phase can be varied from cubic zinc-blende to hexagonal wurtzite structure with an increase of Cu stoichiometry. The inductively coupled plasma optical emission spectrometry (ICP-OES) results reveal that the as-obtained CIZS nanocrystals are Cu-deficient, and the Cu-vacancies have a significant effect on their optical properties. Moreover, the photoluminescence (PL) spectra of the CIZS nanocrystals recorded at different growth periods indicate that the partial cation exchange of Cu+ and In3+ with Zn2+ takes charge of the growth process. After coating a ZnS shell over the CIZS nanocrystals, the PL quantum yield (PLQY) is improved greatly and a blue-shift of the PL peak is observed as compared to that of plain CIZS nanocrystals. More interestingly, the highly luminescent CIZS/ZnS core/shell nanocrystals with different colors have been incorporated into poly(dimethylsiloxane) (PDMS) to be fabricated on an engraved “BJTU” glass substrate, and the as-obtained PDMS membranes exhibit a bright emission under UV light, which also show good stability when they are bent arbitrarily or immersed in water. This heating-up method has also been extended to the preparation of five-component Cu–Ag–In–Zn–S and Cu–Mn–In–Zn–S nanocrystals, which possess a cubic zinc-blende crystal structure and have bright luminescence. Our work may shed light on the synthesis of multi-component semiconductor nanocrystals.
研究领域:
材料科学
·
纳米技术
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2024
·
IF 18.5
Fan Ye,Cangshuang He,Tong Wu,Shuo Chen,Zhenghua Su,Xianghua Zhang,Xingmin Cai,Guangxing Liang
Kesterite Cu 2 ZnSnS 4 (CZTS) solar cells with CdS buffer layers have the problem of toxicity and cliff-like energy band diagram disfavoring higher photoelectric conversion efficiency (PCE (%)). The preparation method for ZnSnO buffer layers which enable Cd-free CZTS solar cells to reach the certified PCE (%) of 11.4 is limited to atomic layer deposition and sputtering deposition severely reduces PCE (%). Here, it is showed that sputtering deposited ZnSnN 2 is an efficient buffer layer for Cd-free CZTS solar cell, and without antireflection coating or additional passivation layers its champion PCE (%) has reached 10.00 which is comparable to the certified value. No buried junction and current blocking behavior are observed in the CZTS\ZnSnN 2 junctions. Elemental inter-diffusion is observed at the interface between CZTS and ZnSnN 2 . Most importantly, the energy band of ZnSnN 2 is well-matched with that of CZTS. The former straddles the latter. The conduction band offset is spike-like with the conduction band of ZnSnN 2 higher than that of CZTS, which effectively suppresses interface recombination and results in PCE (%) comparable to the certified value.
研究领域:
材料科学
·
可再生能源
·
光伏技术
✓ 已验证
DOI
高影响因子
ACS Applied Nano Materials
·
2022
·
IF 6.14
Yue Qin,Huimin Zhang,Qilin Yuan,Hanzhuang Zhang,Jiajia Ning,Wenyu Ji
Inorganic semiconductor nanocrystals (NCs) are considered potential emitters for next-generation displays due to their special quantum size confinement effect. Herein, Cd-free AgInZnS (AIZS) NCs were produced via the cation exchange reaction from AgIn5S8 NCs for light-emitting diodes as green emitters. AIZS NC-based light-emitting diodes showed a maximum current efficiency of 6.34 cd/A and an external quantum efficiency of 1.3%, which are the highest values for AIZS NC-based light-emitting diodes for green emitters so far. The composition of AIZS NCs produced with different ligands can vary the band gap structure of AIZS NCs, affecting the balance of charge injections in the device to induce different performances of AIZS NC-based light-emitting diodes.
研究领域:
材料科学
·
纳米技术
·
光电领域
✓ 已验证
DOI
高影响因子
ORGANIC ELECTRONICS
·
2020
·
IF 3.31
Rongmei Yu,Furong Yin,Chunying Pu,Haizhen Song,Xiumei Xu,Han Zhang,Wenyu Ji
Although much effort has been made to the cadmium-free quantum dot light emitting diodes (QLEDs), it is still a big challenge to achieve an efficient eco-friendly QLED. Here, an extremely efficient QLED based on Ag–In–Zn–S QDs is constructed with the insertion of an 1,3,5-tris(N-phenylbenzimidazole-2-yl)benzene (TPBi) hole-spacing interlayer. The electrical properties of single carrier devices demonstrate the TPBi blocks the hole injection, leading to a more balanced charge injection in the device. Transient electroluminescence measurements confirm that the hole accumulation adjacent QDs is dramatically suppressed after the insertion of TPBi, hence limiting the interactions between excitons and holes. Consequently, the peak current (power) efficiency of 6.0 cd/A (6.5 lm/W) is achieved. To the best of our knowledge, this is the record efficiency for the Ag–In–Zn–S QLEDs reported to date. We anticipate this work will provide a new route for optimizing the performance of Cd-free QLEDs.
研究领域:
材料科学
·
光电子学
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2021
·
IF 9.229
Wenwei Lin,Wen-Ti Guo,Liquan Yao,Jianmin Li,Limei Lin,Jian-Min Zhang,Shuiyuan Chen,Guilin Chen
Hydrothermal deposition is emerging as a highly potential route for antimony-based solar cells, in which the Sb2(S,Se)3 is typically in situ grown on a common toxic CdS buffer layer. The narrow band gap of CdS causes a considerable absorption in the short-wavelength region and then lowers the current density of the device. Herein, TiO2 is first evaluated as an alternative Cd-free buffer layer for hydrothermally derived Sb2S3 solar cells. But it suffers from a severely inhomogeneous Sb2S3 coverage, which is effectively eliminated by inserting a Zn(O,S) layer. The surface atom of sulfur in Zn(O,S) uniquely provides a chemical bridge to enable the quasi-epitaxial deposition of Sb2S3 thin film, confirming by both morphology and binding energy analysis using DFT. Then the results of the first-principles calculations also show that Zn(O,S)/Sb2S3 has a more stable structure than TiO2/Sb2S3. The resultant perfect Zn(O,S)/Sb2S3 junction, with a suitable band alignment and excellent interface contact, delivers a remarkably enhanced JSC and VOC for Sb2S3 solar cells. The device efficiency with the TiO2/Zn(O,S) buffer layer boosts from 0.54% to 3.70% compared with the counterpart of TiO2, which has a champion efficiency of Cd-free Sb2S3 solar cells with a structure of ITO/TiO2/Zn(O,S)/Sb2S3/Carbon/Ag by in situ hydrothermal deposition. This work provides a guideline for the hydrothermal deposition of antimony-based films upon a nontoxic buffer layer.
研究领域:
材料科学
·
太阳能
·
半导体物理
✓ 已验证
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）