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1.
Small ; 20(37): e2401701, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38705844

RESUMO

Enhancing the intrinsic stability of perovskite and through encapsulation to isolate water, oxygen, and UV-induced decomposition are currently common and most effective strategies in perovskite solar cells. Here, the atomic layer deposition process is employed to deposit a nanoscale (≈100 nm), uniform, and dense Al2O3 film on the front side of perovskite devices, effectively isolating them from the erosion caused by water and oxygen in the humid air. Simultaneously, nanoscale (≈100 nm) TiO2 films are also deposited on the glass surface to efficiently filter out the ultraviolet (UV) light in the light source, which induces degradation in perovskite. Ultimately, throughthe collaborative effects of both aspects, the stability of the devices is significantly improved under conditions of humid air and illumination. As a result, after storing the devices in ambient air for 1000 h, the efficiency only declines to 95%, and even after 662 h of UV exposure, the efficiency remains at 88%, far surpassing the performance of comparison devices. These results strongly indicate that the adopted Al2O3 and TiO2 thin films play a significant role in enhancing the stability of perovskite solar cells, demonstrating substantial potential for widespread industrial applications.

2.
Angew Chem Int Ed Engl ; 63(22): e202403739, 2024 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-38565430

RESUMO

Deep-blue perovskite light-emitting diodes (PeLEDs) based on quasi-two-dimensional (quasi-2D) systems exist heightened sensitivity to the domain distribution. The top-down crystallization mode will lead to a vertical gradient distribution of quantum well (QW) structure, which is unfavorable for deep-blue emission. Herein, a thermal gradient annealing treatment is proposed to address the polydispersity issue of vertical QWs in quasi-2D perovskites. The formation of large-n domains at the upper interface of the perovskite film can be effectively inhibited by introducing a low-temperature source in the annealing process. Combined with the utilization of NaBr to inhibit the undesirable n=1 domain, a vertically concentrated QW structure is ultimately attained. As a result, the fabricated device delivers a narrow and stable deep-blue emission at 458 nm with an impressive external quantum efficiency (EQE) of 5.82 %. Green and sky-blue PeLEDs with remarkable EQE of 21.83 % and 17.51 % are also successfully achieved, respectively, by using the same strategy. The findings provide a universal strategy across the entire quasi-2D perovskites, paving the way for future practical application of PeLEDs.

3.
Angew Chem Int Ed Engl ; : e202415681, 2024 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-39324407

RESUMO

The rapid oxidation of Sn2+ in tin-based perovskite solar cells (TPSCs) restricts their efficiency and stability have been main bottleneck towards further development. This study developed a novel strategy which utilizes thiosulfate ions (S2O32-) in the precursor solution to enable a dual-stage reduction process. In the solution stage, thiosulfate acted as an efficacious reducing agent to reduce Sn4+ to Sn2+, meanwhile, its oxidation products were able to reduce I2 to I- during the film stage. This dual reduction ability effectively inhibited the oxidation of Sn2+ and passivated defects, further promising an excellent stability of the perovskite devices. As a result, thiosulfate-incorporated devices achieved a high efficiency of 14.78% with open-circuit voltage reaching 0.96 V. The stability of the optimized devices achieved a remarkable improvement, maintaining 90% of their initial efficiencies after 628 hours at maximum-power-point (MPP). The findings provid research insights and experimental data support for the sustained dynamic reduction in TPSCs.

4.
Angew Chem Int Ed Engl ; : e202412915, 2024 Jul 31.
Artigo em Inglês | MEDLINE | ID: mdl-39083335

RESUMO

The device performance of deep-blue perovskite light-emitting diodes (PeLEDs) is primarily constrained by low external quantum efficiency (EQE) especially poor operational stability. Herein, we develop a facile strategy to improve deep-blue emission through rational interface engineering. We innovatively reported the novel electron transport material, 4,6-Tris(4-(diphenylphosphoryl)phenyl)-1,3,5-triazine (P-POT2T), and utilized a sequential wet-dry deposition method to form homogenic gradient interface between electron transport layer (ETL) and perovskite surface. Unlike previous reports that achieved carrier injection balance by inserting new interlayers, our strategy not only passivated uncoordinated Pb in the perovskite via P=O functional groups but also reduced interfacial carrier recombination without introducing new interfaces. Additionally, this strategy enhanced the interface contact between the perovskite and ETL, significantly boosting device stability. Consequently, the fabricated deep-blue PeLEDs delivered an external quantum efficiency (EQE) exceeding 5% (@ 460 nm) with an exceptional halftime extended to 31.3 minutes. This straightforward approach offers a new strategy to realize highly efficient especially stable PeLEDs.

5.
Angew Chem Int Ed Engl ; 63(7): e202318133, 2024 Feb 12.
Artigo em Inglês | MEDLINE | ID: mdl-38168100

RESUMO

Buried interface modification can effectively improve the compatibility between interfaces. Given the distinct interface selections in perovskite solar cells (PSCs), the applicability of a singular modification material remains limited. Consequently, in response to this challenge, we devised a tailored molecular strategy based on the electronic effects of specific functional groups. Therefore, we prepared three distinct silane coupling agents, and due to the varying inductive effects of these functional groups, the electronic distribution and molecular dipole moments of the coupling agents are correspondingly altered. Among them, trimethoxy (3,3,3-trifluoropropyl)-silane (F3 -TMOS), which possesses electron-withdrawing groups, generates a molecular dipole moment directed toward the hole transport layer (HTL). This approach changes the work function of the HTL, optimizes the energy level alignment, reduces the open-circuit voltage loss, and facilitates carrier transport. Furthermore, through the buffering effect of the coupling agent, the interface strain and lattice distortion caused by annealing the perovskite are reduced, enhancing the stability of the tin-based perovskite. Encouragingly, tin PSCs treated with F3 -TMOS achieved a champion efficiency of 14.67 %. This strategy provides an expedient avenue for the design of buried interface modification materials, enabling precise molecular adjustments in accordance with distinct interfacial contexts to ameliorate mismatched energetics and enhance carrier dynamics.

6.
Angew Chem Int Ed Engl ; 63(39): e202406140, 2024 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-38981859

RESUMO

Blue perovskite light-emitting diodes (PeLEDs) are crucial avenues for achieving full-color displays and lighting based on perovskite materials. However, the relatively low external quantum efficiency (EQE) has hindered their progression towards commercial applications. Quasi-two-dimensional (quasi-2D) perovskites stand out as promising candidates for blue PeLEDs, with optimized control over low-dimensional phases contributing to enhanced radiative properties of excitons. Herein, the impact of organic molecular dopants on the crystallization of various n-phase structures in quasi-2D perovskite films. The results reveal that the highly reactive bis(4-(trifluoromethyl)phenyl)phosphine oxide (BTF-PPO) molecule could effectively restrain the formation of organic spacer cation-ordered layered perovskite phases through chemical reactions, simultaneously passivate those uncoordinated Pb2+ defects. Consequently, the prepared PeLEDs exhibited a maximum EQE of 16.6 % (@ 490 nm). The finding provides a new route to design dopant molecules for phase modulation in quasi-2D PeLEDs.

7.
Scand J Gastroenterol ; 58(12): 1514-1522, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37545358

RESUMO

BACKGROUND: Graves' hyperthyroidism (GH) is often accompanied by mild to moderate liver injury, but severe hepatic dysfunction (SHD) is relatively rare. Whether patients with GH-related SHD can be treated with methimazole (MMI) remains controversial. This study aimed to determine the clinical characteristics and to evaluate the role of low-dose MMI for such patients. METHODS: 33 patients with GH-related SHD were selected for this retrospective study in the Fifth Medical Center of Chinese PLA General Hospital from January 2017 to July 2022. The clinical manifestations, therapeutic responses, and effectiveness of MMI were evaluated. RESULTS: Systemic jaundice (100.0%), yellow urine (100.0%), fatigue (87.9%), and goiter (66.7%) were the main symptoms. Total bilirubin (TBIL) had no linear correlation with free triiodothyronine (FT3) (r = -0.023, p = .899), free thyroxine (FT4) (r = 0.111, p = .540), T3 (r = -0.144, p = .425), and T4 (r = 0.037, p = .837). On the 14th day after admission, FT3, FT4, T3, T4, TBIL, direct bilirubin (DBIL), alanine transaminase (ALT), aspartate transaminase (AST), alkaline phosphatase (ALP), γ-glutamyltransferase (GGT), and international normalized ratio (INR) decreased compared with the baseline (p < .05). The decrease rates of FT3, FT4, T3, T4, TBIL, and DBIL in the MMI group were higher than those in the non-MMI group (p < .05). The improvement rate of the MMI group (77.8%) was higher than that of the non-MMI group (9.5%, p = .001). MMI treatment is an independent predictor affecting the early improvement of patients (OR = 0.022, p = .010). CONCLUSIONS: The main clinical manifestations of patients with GH-related SHD were symptoms related to liver disease. Low-dose MMI was safe and effective for them.


Assuntos
Doença de Graves , Hipertireoidismo , Hepatopatias , Humanos , Metimazol/uso terapêutico , Antitireóideos/uso terapêutico , Estudos Retrospectivos , Doença de Graves/complicações , Doença de Graves/tratamento farmacológico , Doença de Graves/induzido quimicamente , Tiroxina/uso terapêutico , Hipertireoidismo/complicações , Hipertireoidismo/tratamento farmacológico , Hipertireoidismo/induzido quimicamente , Hepatopatias/complicações , Bilirrubina
8.
Environ Res ; 236(Pt 2): 116834, 2023 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-37544466

RESUMO

Antimony (Sb) is a toxic substance that poses a serious ecological threat when released into the environment. The species and redox state of Sb determine its environmental toxicity and fate. Understanding the redox transformations and biogeochemical cycling of Sb is crucial for analyzing and predicting its environmental behavior. Dissolved organic matter (DOM) in the environment greatly affects the fate of Sb. Microbially produced DOM is a vital component of environmental DOM; however, its specific role in Sb(III) oxidation has not been experimentally confirmed. In this work, the oxidation capacity of several Shewanella strains and their derived DOM to Sb(III) was confirmed. The oxidation rate of Sb(III) shows a positive correlation with DOM concentration, with higher rates observed under neutral and weak alkaline conditions, regardless of the presence of light. Incubation experiments indicated that extracellular enzymes and common reactive oxygen species were not involved in the oxidation of Sb(III). Characteristics of DOM suggests that microbial humic acid-like and fulvic acid-like substances are the potential contributors to Sb(III) oxidation. These findings not only experimentally validate the role of bacterial-derived DOM in Sb(III) oxidation but also reveal the significance of Shewanella and biogenic DOM in the biogeochemical cycling of Sb.


Assuntos
Shewanella , Oxirredução , Substâncias Húmicas/análise , Antimônio/química , Matéria Orgânica Dissolvida
9.
Angew Chem Int Ed Engl ; 62(21): e202219255, 2023 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-36919897

RESUMO

Achieving efficient blue electroluminescence (EL) remains the fundamental challenge that impedes perovskite light-emitting diodes (PeLEDs) towards commercial applications. The bottleneck accounting for the inefficient blue PeLEDs is broadly attributed to the poor-emissive blue perovskite emitters based on either mixed halide engineering or reduced-dimensional strategy. Herein, we report the high-performing sky-blue PeLEDs (490 nm) with the maximum EQE exceeding 15 % by incorporating a molecular modifier, namely 4,4'-Difluorophenone, for significantly suppressing the non-radiative recombination and tuning of the low-dimensional phase distribution of quasi-2D blue perovskites, which represents a remarkable paradigm for developing the new generation of blue lighting sources.

10.
J Am Chem Soc ; 144(40): 18470-18478, 2022 Oct 12.
Artigo em Inglês | MEDLINE | ID: mdl-36164747

RESUMO

Despite recent encouraging developments, achieving efficient blue perovskite light-emitting diodes (PeLEDs) have been widely considered a critical challenge. The efficiency breakthrough only occurred in the sky-blue region, and the device performance of pure-blue and deep-blue PeLEDs lags far behind those of their sky-blue counterparts. To avoid the negative effects associated with dimensionality reduction and excess chloride typically needed to achieve deep-blue emission, here we demonstrate guanidine (GA+)-induced deep-blue (∼457 nm) perovskite emitters enabling spectrally stable PeLEDs with a record external quantum efficiency (EQE) over 3.41% through a combination of quasi-2D perovskites and halide engineering. Owing to the presence of GA+, even a small inclusion of chloride ions is sufficient for generating deep-blue electroluminescence (EL), in clear contrast to the previously reported deep-blue PeLEDs with significant chloride inclusion that negatively affects spectral stability. Based on the carrier dynamics analysis and theoretical calculation, GA+ is found to stabilize the low-dimensional species during annealing, retarding the cascade energy transfer and facilitating the deep-blue EL. Our findings open a potential third route to achieve deep-blue PeLEDs beyond the conventional methods of dimensionality reduction and excessive chloride incorporation.

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