Yb3+ doped lead‐free double perovskites (DPs) with near‐infrared (NIR)‐emitting have attracted extensive attention due to their wide application prospects. Unfortunately, they still suffer from weak ...NIR emission due to undesirable resonance energy transfer between the sensitizers and Yb3+ ions. Herein, a new effective NIR‐emitting DP is developed by co‐doping Sb3+ and Yb3+ into Cs2AgInCl6. Experiments and theoretical calculations reveal that induced by co‐doping Sb3+ ions, the self‐trapped excitation (STE) emission intensity of Cs2AgInCl6 is greatly enhanced by 240 times, and the STE emission shifts from 600 nm to 660 nm, which contributes to a larger spectral overlap between STE emission and the absorption of Yb3+ ions. As a result, the absolute NIR photoluminescence quantum yield reaches an unprecedented 50% in lead‐free DPs via high‐efficiency STE sensitization (>30%). The excellent optical performance of Cs2AgInCl6: Sb, Yb with high ambient, thermal and light stability makes it suitable for application in night‐vision devices. Moreover, an ingenious dual‐modal optical information encryption based on the combination of visible and NIR fluorescence printing patterns utilizing Cs2AgInCl6: Sb and Cs2AgInCl6: Sb, Yb respectively is successfully demonstrated. This study provides inspiration for designing highly efficient NIR‐emitting Ln3+‐doped DPs and illustrates their great potential in versatile optoelectronic applications.
A new design strategy of Sb3+ ions co‐doping in Cs2AgInCl6:Yb3+ is proposed to expand absorption region to longer wavelengths and effectively enhance the near‐infrared emission of Yb3+ ions. The excellent sensitization efficiency from self‐trapped exciton to Yb3+ ions (>30%) gives Sb3+, Yb3+ co‐doped Cs2AgInCl6 unprecedented near‐infrared emission with a photoluminescence quantum yield of up to 50%.
Abstract Yb 3+ doped lead‐free double perovskites (DPs) with near‐infrared (NIR)‐emitting have attracted extensive attention due to their wide application prospects. Unfortunately, they still suffer ...from weak NIR emission due to undesirable resonance energy transfer between the sensitizers and Yb 3+ ions. Herein, a new effective NIR‐emitting DP is developed by co‐doping Sb 3+ and Yb 3+ into Cs 2 AgInCl 6 . Experiments and theoretical calculations reveal that induced by co‐doping Sb 3+ ions, the self‐trapped excitation (STE) emission intensity of Cs 2 AgInCl 6 is greatly enhanced by 240 times, and the STE emission shifts from 600 nm to 660 nm, which contributes to a larger spectral overlap between STE emission and the absorption of Yb 3+ ions. As a result, the absolute NIR photoluminescence quantum yield reaches an unprecedented 50% in lead‐free DPs via high‐efficiency STE sensitization (>30%). The excellent optical performance of Cs 2 AgInCl 6 : Sb, Yb with high ambient, thermal and light stability makes it suitable for application in night‐vision devices. Moreover, an ingenious dual‐modal optical information encryption based on the combination of visible and NIR fluorescence printing patterns utilizing Cs 2 AgInCl 6 : Sb and Cs 2 AgInCl 6 : Sb, Yb respectively is successfully demonstrated. This study provides inspiration for designing highly efficient NIR‐emitting Ln 3+ ‐doped DPs and illustrates their great potential in versatile optoelectronic applications.
The high quality CsPbBr3-Cs4PbBr6 perovskite composites solids were synthesized by a single atomic supersaturated recrystallization method.
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Here, we present a single atomic ...supersaturated recrystallization method to synthesize the green-emitting CsPbBr3-Cs4PbBr6 perovskite composites in solid state with the highest PLQY of 40.8% in pure polar solvent. The component, morphology, and optical properties of the microcrystals can be tuned by varying growth time, the content of ammonium bromide, and bromine source. The developed method provides a new route to large-scale synthesize high quality perovskite composites emitters for light-emitting diodes.
Nowadays, due to uncontrolled synthesis and lack of more direct and systematic evidences, the photoluminescence origin of “zero-dimensional” Cs
4
PbI
6
remains great controversy and the luminescence ...cannot be controlled. Here we propose a controllable dissolution-recrystallization method to synthesize “emissive” and “non-emissive” Cs
4
PbI
6
nanocrystals (NCs) respectively. Through comparing “emissive” and “non-emissive” Cs
4
PbI
6
NCs, it is clearly proved that the visible emission in “emissive” Cs
4
PbI
6
NCs comes from embedded CsPbI
3
quantum dots (QDs). It is found for CsPbI
3
@Cs
4
PbI
6
nanocomposites, methyl acetate (MeAC) and cyclohexane play an important role in dissolution and recrystallization respectively to obtain Cs
4
PbI
6
matrix and CsPbI
3
cores. Benefiting from this two-step method, the as-synthesized CsPbI
3
@Cs
4
PbI
6
nanocomposites with CsPbI
3
QDs uniformly distributed in Cs
4
PbI
6
matrix are bright with photoluminescence quantum yield (PLQY) up to 71.4% and exhibit improved stability than CsPbI
3
NCs. Moreover, utilizing its formation mechanism, the size of embedded CsPbI
3
QDs can be controlled by reasonable designing the “dissolution” process, so that the luminescence of this CsPbI
3
@Cs
4
PbI
6
nanocomposites can be adjusted in a wide range from green to red (554–630 nm). Our finding not only provides a novel method for synthesizing tunable “emissive” Cs
4
PbI
6
NCs, but also makes clear the photoluminescence origin of “emissive” Cs
4
PbI
6
.
Here, we present a single atomic supersaturated recrystallization method to synthesize the green-emitting CsPbBr
-Cs
PbBr
perovskite composites in solid state with the highest PLQY of 40.8% in pure ...polar solvent. The component, morphology, and optical properties of the microcrystals can be tuned by varying growth time, the content of ammonium bromide, and bromine source. The developed method provides a new route to large-scale synthesize high quality perovskite composites emitters for light-emitting diodes.
Drugs that target the human serotonin 2A receptor (5-HT
R) are used to treat neuropsychiatric diseases; however, many have hallucinogenic effects, hampering their use. Here, we present structures of ...5-HT
R complexed with the psychedelic drugs psilocin (the active metabolite of psilocybin) and d-lysergic acid diethylamide (LSD), as well as the endogenous neurotransmitter serotonin and the nonhallucinogenic psychedelic analog lisuride. Serotonin and psilocin display a second binding mode in addition to the canonical mode, which enabled the design of the psychedelic IHCH-7113 (a substructure of antipsychotic lumateperone) and several 5-HT
R β-arrestin-biased agonists that displayed antidepressant-like activity in mice but without hallucinogenic effects. The 5-HT
R complex structures presented herein and the resulting insights provide a solid foundation for the structure-based design of safe and effective nonhallucinogenic psychedelic analogs with therapeutic effects.
Ecological and cultural forestry need to be integrated for successful rural revitalization. A proper rural revitalization strategy should be linked to the value of the eco-cultural forestry industry. ...To adjust and optimize the structure of this industry, we need to develop the primary and tertiary industries and structurally optimize the secondary industry. The sustainable development of forestry requires us to promote the unity of the ecological, social, and economic benefits of forestry. By unifying ecological forestry and the cultural industry, we can capture consumer market trends, enhance industrial development policies, and increase the training of high-level talents to better deal with the danger of industrial hollowing out and resolve the embarrassment of the low end of the value chain. By integrating and promoting the two systems of ecological forestry and the cultural industry, we can converge their respective values and allow more nuanced value cognition when exploring the development paths of industry integration. In the period of overall transfer of forestry development strategy, it is of great significance to develop a forestry economy according to the evolution law of forestry industry, give full play to the advantages of forestry ecological culture resources, and vigorously develop forestry ecological culture industry under the background of rural revitalization strategy. Based on the integration of forestry industry, the aim of this study is to summarize the forestry ecological culture industry development mechanism, summarize the value of forestry ecological culture industry development strategy, put forward building a new era forestry ecological culture industry system, capture the consumer market trend, optimize industrial development policy, increase the high-level talent training industry integration development path, improve rural ecological advantages into ecological economic advantages, provide more and better green ecological products and services, promote the ecological and economic virtuous cycle, and realize the sustainable development of the forestry economy.
•Initiation of IVIG as adjuvant treatment for COVID-19 pneumonia within 48 h of admission to the ICU can reduce the use of mechanical ventilation.•Initiation of IVIG as adjuvant treatment for ...COVID-19 pneumonia within 48 h of admission to the ICU can reduce hospital length of stay and length of stay in ICU.•Initiation of IVIG as adjuvant treatment for COVID-19 pneumonia within 48 h of admission to the ICU can reduce 28-day mortality of patients with severe COVID-19 pneumonia.
We are witnessing a fast development of Artificial Intelligence (AI), but it becomes dramatically challenging to explain AI models in the past decade. "Explanation" has a flexible philosophical ...concept of "satisfying the subjective curiosity for causal information", driving a wide spectrum of methods being invented and/or adapted from many aspects and communities, including machine learning, visual analytics, human-computer interaction and so on. Nevertheless, from the view-point of data and knowledge engineering (DKE), a best explaining practice that is cost-effective in terms of extra intelligence acquisition should exploit the causal information and explaining scenarios which is hidden richly in the data itself. In the past several years, there are plenty of works contributing in this line but there is a lack of a clear taxonomy and systematic review of the current effort. To this end, we propose this survey, reviewing and taxonomizing existing efforts from the view-point of DKE, summarizing their contribution, technical essence and comparative characteristics. Specifically, we categorize methods into data-driven methods where explanation comes from the task-related data, and knowledge-aware methods where extraneous knowledge is incorporated. Furthermore, in the light of practice, we provide survey of state-of-art evaluation metrics and deployed explanation applications in industrial practice.
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