Advanced Optical Materials
·
2023
·Vol. 11
·期 14
·2300248
·
IF 9
Huayu Wei,Chenlin Wang,Xiaoxiao Li,Heyan Meng,Bingyi Tong,Luxi Li,Xuepeng Zhan,Bing Jin,Baoqing Sun,Yanmin Zong,Xian Zhao,Yuan Gao
Cadmium chalcogenide colloidal quantum wells (CQWs) are a unique class of optical gain materials that can be precisely engineered in terms of thickness and composition at the atomic level using colloidal atomic layer deposition (c-ALD). However, the atomic layer deposition is typically performed at room temperature, resulting in low emission efficiency and the need for additional thermal annealing. In this study, ultraviolet (UV) illumination is used to treat the CQWs prepared using c-ALD and a significant improvement in their photoluminescence is observed, with an irreversible 79-fold increase. Furthermore, the lasing threshold is reduced to two-thirds of the untreated samples, enabling whispering gallery mode lasing from the CQW in solution. This research demonstrates an efficient and convenient method for boosting the emission from the CQWs and highlights the advantages of CQWs as optical gain media that can be engineered with atomic precision.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
MATERIALS CHEMISTRY AND PHYSICS
·
2025
·
IF 4.7
Jinkun Xue,Hao Hu,Wen Li,Yongrun Dong,Zequan Li,Wei Gao
As a new type of zero-dimensional nanoluminescent material, carbon dots (CDs) have attracted extensive attention and in-depth research in recent years due to their rich and excellent luminescence properties. In this study, sodium-doped CDs (Na-CDs) were synthesized under three different sodium source conditions by hydrothermal method, and the regulation mechanism of Na-doped on the structure and optical properties of CDs was systematically studied by comparing with undoped control samples. The results show that Na-doped does not significantly change the particle size and crystal structure of CDs, but can significantly increase the proportion of graphite nitrogen (from 12.3 % to 65.3 %), enhance the order of sp 2 carbon structure, thereby effectively inhibiting π-π stacking, and significantly improving the fluorescence quenching problem of CDs in the solid state. Among them, the self-doped CDs-1 exhibits strong and stable blue fluorescence in both solution and solid state, with emission peaks at 447 nm and 455 nm, respectively, phosphorescence quantum yields (PLQY) of 22.61 % and 9.02 %, respectively, and an average fluorescence lifetime of 7.75 ns, which is much higher than other samples. Temperature response experiments show that the fluorescence intensity of CDs-1 shows a decay trend with increasing temperature in the range of 80–300 K, and shows a good linear relationship in the range of 160–300 K. The fluorescence intensity decreases by an average of 0.0191 % for every increase of 1 K, showing excellent temperature sensitivity and stability. This study provides new ideas for the design of high-performance solid-state luminescent CDs and expands their application potential in the field of optical functional materials such as non-contact temperature sensing.
研究领域:
材料科学
·
纳米光学
·
功能材料
·
物理化学
·
传感器技术
✓ 已验证
产品关联
DOI
高影响因子
OPTICAL MATERIALS
·
2020
·
IF 2.779
Yuxin Pan,Hui Lin,Jian Liu,Xiaodong Xu,Ruijin Hong,Chunxian Tao,Zhaoxia Han,Dawei Zhang
Yb,Ho:Y 2 O 3 ceramics have been fabricated by Spark Plasma Sintering method (SPS). The microstructure and transmittance of the ceramics sintered from 1623 K to 1673 K were analyzed. The highest in-line transmittance of Yb,Ho:Y 2 O 3 ceramic sintered at 1673 K reached almost 83% at 750 nm with the thickness of 1 mm. The absorption spectra , fluorescence spectra and fluorescence decay curve were recorded at room temperature. The Judd-Ofelt parameters Ω 2 , Ω 4 and Ω 6 were calculated to be 8.33 × 10 −20 cm 2 , 1.81 × 10 −20 cm 2 , and 0.82 × 10 −20 cm 2 , respectively. The intense emission cross section of Yb,Ho:Y 2 O 3 ceramic was 3.43 × 10 −20 cm 2 at 2057 nm with full width at half maximum (FWHM) of 208 nm. The results indicate that Yb,Ho:Y 2 O 3 transparent ceramic can be a promising laser gain medium for laser operation around 2 μm.
研究领域:
材料科学
·
光学工程
✓ 已验证
产品关联
DOI
高影响因子
ADVANCED FUNCTIONAL MATERIALS
·
2022
·Vol. 33
·期 1
·2210278
·
IF 19.924
Xiaohui Lin,Long Chen,Chenglin He,Yiliu Wang,Xu Li,Weiqi Dang,Kun He,Ying Huangfu,Dan Wu,Bei Zhao,Bo Li,Jia Li,Xidong Duan
Single crystal metal halide perovskites thin films are considered to be a promising optical, optoelectronic materials with extraordinary performance due to their low defect densities. However, it is still difficult to achieve large-scale perovskite single-crystal thin films (SCTFs) with tunable bandgap by vapor-phase deposition method. Herein, the synthesis of CsPbCl 3(1– x ) Br 3 x SCTFs with centimeter size (1 cm × 1 cm) via vapor-phase deposition is reported. The Br composition of CsPbCl 3(1– x ) Br 3 x SCTFs can be gradually tuned from x = 0 to x = 1, leading the corresponding bandgap to change from 2.29 to 2.91 eV. Additionally, an low-threshold (≈23.9 µJ cm −2 ) amplified spontaneous emission is achieved based on CsPbCl 3(1– x ) Br 3 x SCTFs at room temperature, and the wavelength is tuned from 432 to 547 nm by varying the Cl/Br ratio. Importantly, the high-quality CsPbCl 3(1– x ) Br 3 x SCTFs are ideal optical gain medium with high gain up to 1369.8 ± 101.2 cm −1 . This study not only provides a versatile method to fabricate high quality CsPbCl 3(1– x ) Br 3 x SCTFs with different Cl/Br ratio, but also paves the way for further research of color-tunable perovskite lasing.
研究领域:
材料科学
·
光学
·
凝聚态物理
·
半导体物理
·
光电子学
·
纳米科技
·
功能材料
✓ 已验证
DOI
高影响因子
ADVANCED MATERIALS
·
2017
·Vol. 29
·期 32
·1700439
·
IF 19.791
Lei Fu,Feng Wang,Bin Wu,Nian Wu,Wei Huang,Hanlin Wang,Chuanhong Jin,Lin Zhuang,Jun He,Lei Fu,Yunqi Liu
As a member of the group IVB transition metal dichalcogenides (TMDs) family, hafnium disulfide (HfS 2 ) is recently predicted to exhibit higher carrier mobility and higher tunneling current density than group VIB (Mo and W) TMDs. However, the synthesis of high-quality HfS 2 crystals, sparsely reported, has greatly hindered the development of this new field. Here, a facile strategy for controlled synthesis of high-quality atomic layered HfS 2 crystals by van der Waals epitaxy is reported. Density functional theory calculations are applied to elucidate the systematic epitaxial growth process of the S-edge and Hf-edge. Impressively, the HfS 2 back-gate field-effect transistors display a competitive mobility of 7.6 cm 2 V −1 s −1 and an ultrahigh on/off ratio exceeding 10 8 . Meanwhile, ultrasensitive near-infrared phototransistors based on the HfS 2 crystals (indirect bandgap ≈1.45 eV) exhibit an ultrahigh responsivity exceeding 3.08 × 10 5 A W −1 , which is 10 9 -fold higher than 9 × 10 −5 A W −1 obtained from the multilayer MoS 2 in near-infrared photodetection. Moreover, an ultrahigh photogain exceeding 4.72 × 10 5 and an ultrahigh detectivity exceeding 4.01 × 10 12 Jones, superior to the vast majority of the reported 2D-materials-based phototransistors, imply a great promise in TMD-based 2D electronic and optoelectronic applications.
研究领域:
材料科学
·
纳米技术
·
半导体器件
·
光电子学
·
凝聚态物理
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）