NANOTECHNOLOGY
·
2019
·Vol. 30
·期 26
·265704
·
IF 3.399
Yujuan Fan,Xingfa Yang,Chaoshun Yin,Chenao Ma,Xingping Zhou
In the past decade, hydrophobic fluorescent carbon dots (OCDs) have received little attention, and its potential application and light transition mechanism is seldom explored. Here we report a novel one-step approach for synthesizing blue- and green-emitting hydrophobic fluorescent carbon dots (OCDb and OCDg) by calcinating with the uses of citric acid and hexadecylamine as initial reactants. The optimal conditions for preparing OCDb and OCDg were obtained by using the Taguchi L25 (35) orthogonal array. The highest quantum yield and product yield of OCDs reached 80.2% and 57.1%, respectively, larger than those from most of all the known reports. The fluorescent stability of OCDb and OCDg was excellent under UV irradiation (30 W) for days. The luminescent color of OCDs showed a great dependence on reaction conditions. It is easier to get OCDg via a reaction kept at a high temperature for a long time. The optical transition mechanism was studied for the two kinds of color OCDs, and therefore proposed in combination with their optical properties and surface groups. The reason for light transition is probably related to an appropriate critical ratio and surface density of the C=O and N–H bond in the surface structure of the product. For the OCDg, the concentration matching ratio of N–H and C=O bonds in the surface structure of the green-emitting product is approximately between d/2 and 3d/2, where d is a fixed constant. Lower than or higher than this critical ratio range, the product emits blue light. Based on their high fluorescence quantum efficiency and the advantages mentioned above, these OCDs were then respectively used for preparing hydrophobic fluorescent carbon dot-loading liposomes and acrylate films, both exhibiting a perfect performance with no fluorescence quenching.
研究领域:
化学
·
材料科学
✓ 已验证
DOI
高影响因子
CERAMICS INTERNATIONAL
·
2022
·
IF 5.532
Ou Hai,Jian Li,Mengkang Pei,Qiang Ren,Xiulan Wu
The construction of visible full-spectrum tunable afterglow luminescence is of great significance for long afterglow materials. Here we developed a new composite material whose afterglow were continuously tunable from blue to red light, we prepared CsPbI 3 quantum dots (QDs) by thermal injection method and added passivators to obtain relatively more stable QDs materials, the SDS-CsPbI 3 QDs after passivation treatment was more than twice the photoluminescent (PL) intensity of the original QDs after 10 days, which has a positive effect on the large-scale production and application of all-inorganic perovskite QDs. By uniformly distributing CsPbI 3 QDs on the surface of Sr 2 MgSi 2 O 7 :Eu 2+ ,Dy 3+ (SMS) by Stöber method, a color-tunable long-persistence luminescent material CsPbI 3 /SMS@SiO 2 was prepared, and the tunable afterglow glows from 465 nm to 700 nm was realized by optical conversion. In addition, the PL intensity of the composite material under ultraviolet light is increased by more than 50%, and it can remain stable for a long time; its high temperature resistance is also improved to 140 °C; and the luminous intensity after 10 days remains at a high level. This research also provides new ideas and methods for the development of multicolor long afterglow materials.
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
Advanced Materials Interfaces
·
2022
·Vol. 9
·期 15
·2102566
·
IF 6.389
Yi Yin,Haoyu Zhu,Tao Wu,Pengkun Liao,Changyong Lan,Chun Li
A bistable electrochromic (EC) device which can reversibly transform between transparent, mirror, and black states based on reversible metal Ag electrodeposition is achieved by introducing 1) a (3-mercaptopropyl) trimethoxysilane (MPTMS)-treated indium-tin-oxide (ITO) glass electrode modified with WO 3 nanoislands (WNs) as the rough surface and 2) ionic liquids (IL) into electrolyte to form an anion-blocking layer, toward achieving long-term memory performance. Typically, the EC cell is packaged by sandwiching gel electrolyte between the flat and WNs-modified ITO electrodes. Under opposite voltages, this smart device can transfer from transparent to black (+2.5 V/9.4 s) or mirror (−2.5 V/8.3 s) state by depositing Ag on the WNs-modified or flat ITO electrode surface, respectively. The assembled device exhibits over 80% mirror reflectance and below 10% transmittance of black state. After power off, both the black and mirror states remain bistability for a long time (>30 min) when IL are introduced into electrolyte for the EC device. The electrical double layer in the highly viscous electrolyte with IL contributes to form a barrier to bromide ions, which protects the Ag layer from dissolution at open circuit. This multifunctional energy-efficient EC device has shown great potential and competitiveness for numerous applications compared to conventional EC devices.
研究领域:
材料科学
·
电化学
✓ 已验证
产品关联
DOI
高影响因子
RSC Advances
·
2016
·Vol. 6
·期 37
·30769-30775
·
IF 3.289
Tao Ye,Yong Xiang,Hong Ji,Congjin Hu,Gang Wu
Reversible electrodeposition-based electrochromic devices are highly promising for extensive applications owing to their facile and low-cost fabrication. Herein, a novel electrodeposition-based electrochromic device with reversible three-state optical transformation, i.e. transparent, mirror, and black, was fabricated by introducing a fluorine-doped tin oxide (FTO) electrode modified with commonly available and inexpensive titanium dioxide (TiO2) nanoparticles. Typically, the fabricating strategy mainly involved three procedures, namely obtaining a stable dispersion of TiO2 nanoparticles by milling, achieving a surface modification of the FTO electrode with TiO2 nanoparticles by spin-coating and sintering, and assembling the device by sandwiching gel electrolyte between the modified FTO electrode and a flat FTO electrode. By applying different voltages for a short while, this transparent smart device can be immediately switched to black (+2.5 V/20 s) or mirror (−2.5 V/20 s) state by depositing Ag on the surface of the modified or unmodified FTO electrode respectively. There is below 1% transmittance in the black state and over 80% reflectance in the mirror state for the device. By changing the surface structure of the TiO2 modified FTO electrode, the optical properties of the device in different states can be controlled effectively. Moreover, the optical transformation exhibited good stability over 1500 cycles of testing.
研究领域:
材料科学
·
电化学
·
光电
✓ 已验证
产品关联
DOI
高影响因子
ACS Applied Materials & Interfaces
·
2022
·
IF 10.383
Tong Wei,Kai Lian,Jiaqi Tao,Hu Zhang,Da Xu,Jiachen Han,Chao Fan,Zihui Zhang,Wengang Bi,Chun Sun
Luminescent solar concentrators (LSCs) can be used as large-area sunlight collectors, which show great potential in the application of building-integrated photovoltaic areas. Achieving highly efficient LSCs requires the suppression of reabsorption losses while maintaining a high photoluminescence quantum yield (PLQY) and broad absorption. Perovskites as the superstar fluorophores have recently emerged as candidates for large-area LSCs. However, highly emissive perovskites with a large Stokes shift and broad absorption have not been obtained up to now. Here, we devised a facile synthetic route to obtain Mn-doped multiple quantum well (MQW) Br-based perovskites. The Br-based perovskite host ensures broad absorption. Efficient energy transfer from the exciton to the Mn dopant produces a large Stokes shift and high PLQY simultaneously. By further coating the perovskites with Al2O3, the stability and PLQY are greatly elevated. A large area of liquid LSC (40 cm × 40 cm × 0.5 cm) is fabricated, which possesses an internal quantum efficiency (ηint) of 47% and an optical conversion efficiency (ηopt) reaching 11 ± 1%, which shows the highest value for large-area LSCs.
研究领域:
材料科学
·
可再生能源
·
太阳能
·
光子学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
危险品化学品经营许可证（带存储）