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1.
Small ; : e2309922, 2024 Apr 09.
Artículo en Inglés | MEDLINE | ID: mdl-38593357

RESUMEN

Self-trapped exciton (STE) luminescence, typically associated with structural deformation of excited states, has attracted significant attention in metal halide materials recently. However, the mechanism of multiexciton STE emissions in certain metal halide crystals remains largely unexplored. This study investigates dual luminescence emissions in HCOO- doped Cs3Cu2I5 single crystals using transient and steady-state spectroscopy. The dual emissions are attributed to intrinsic STE luminescence originating from the host lattice and extrinsic STE luminescence induced by external dopants, respectively, each of which can be triggered independently at distinct energy levels. Theoretical calculations reveal that multiexciton emission originates from structural distortion of the host and dopant STEs within the 0D lattice in their respective excited states. By meticulously tuning the excitation wavelength and selectively exciting different STEs, the dynamic alteration of color change in Cs3Cu2I5:HCOO- crystals is demonstrated. Ultimately, owing to an extraordinarily high photoluminescence quantum yield (99.01%) and a diminished degree of self-absorption in Cs3Cu2I5:HCOO- crystals, they exhibit remarkable X-ray scintillation characteristics with light yield being improved by 5.4 times as compared to that of pristine Cs3Cu2I5 crystals, opening up exciting avenues for achieving low-dose X-ray detection and imaging.

2.
Int J Biol Macromol ; 267(Pt 2): 131657, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38636753

RESUMEN

Porous starch (PS) is a modified starch with commendable biodegradable and adsorption properties. PS exhibits poor thermal stability, and the aqueous solution casting method is conventionally used for PS-activated packaging films. This approach limits the large-scale production of films and makes it difficult to play the functions of porous pores. In this study, PS was prepared by enzymatic digestion combined with freeze-drying and adsorbed with clove essential oil (CEO) after cross-linking with sodium trimetaphosphate. Subsequently, a novel PLA/PBAT/TPS/ScPS-CEO sustained release active packaging film was prepared by blending PLA, PBAT, TPS, and ScPS-CEO using industrial melt extrusion. Compared with PS, ScPS effectively slowed down the release of CEO from the film, with the maximum release of active substances at equilibrium increasing by approximately 100 %, which significantly enhanced the persistence of the antimicrobial and antioxidant properties. The polylactic acid/poly (butylene adipate-co-terephthalate)/thermoplastic starch/trimetaphosphate-crosslinked porous starch incorporated with clove essential oil (PLA/PBAT/TPS/ScPS-CEO) film could reduce the proteolysis, lipid oxidation and microbial growth of salmon, extending its shelf life by approximately 100 % at 4 °C. These results indicate that the ScPS can be used in fresh packaging material in practical applications.


Asunto(s)
Antioxidantes , Poliésteres , Almidón , Almidón/química , Poliésteres/química , Antioxidantes/química , Antioxidantes/farmacología , Porosidad , Antiinfecciosos/farmacología , Antiinfecciosos/química , Preparaciones de Acción Retardada/farmacología , Embalaje de Alimentos/métodos , Temperatura
3.
Nano Lett ; 24(13): 3952-3960, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38527956

RESUMEN

Despite light-emitting diodes (LEDs) based on quasi-two-dimensional (Q-2D) perovskites being inexpensive and exhibiting high performance, defects still limit the improvement of electroluminescence efficiency and stability by causing nonradiative recombination. Here, an organic molecule, 1-(o-tolyl) biguanide, is used to simultaneously inhibit and passivate defects of Q-2D perovskites via in situ synchronous crystallization. This molecule not only prevents surface bromine vacancies from forming through hydrogen bonding with the bromine of intermediaries but also passivates surface defects through its interaction with uncoordinated Pb. Via combination of defect inhibition and passivation, the trap density of Q-2D perovskite films can be significantly reduced, and the emission efficiency of the film can be improved. Consequently, the corresponding LED shows an external quantum efficiency of 24.3%, and its operational stability has been increased nearly 15 times.

4.
Int J Biol Macromol ; 262(Pt 1): 129904, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38311137

RESUMEN

In this research, the carvacrol (CAR) loaded cellulose acetate phthalate (CAP) /shellac (SH) films were prepared via electrostatic repulsion strategy and casting method. The CAP/SH-CAR films demonstrated excellent tensile strength, while also exhibiting good UV light barrier and thermal stability. The results showed that the addition of CAR significantly improved the barrier of the CAP film to water vapor and oxygen permeability. When the addition amount of CAR was 0.9 % (w/w) with respect to CAP content, the CAP/SH-CAR films exhibited good antibacterial activity and effectively reduced the growth of S. aureus and E. coli by approximately 47.9 % and 50.9 %, respectively. The presence of SH improved the retention rate of CAR in CAP/SH-CAR films, with the retention rate ranging from 45.2 to 56.8 %. Finally, the CAP/SH-CAR films were applied to preserve the mackerel fillets, indicating that the rate of freshness deterioration had been delayed and showing a good freshness preservation effect. Therefore, the CAP/SH-CAR films have the potential to be used as food packaging materials.


Asunto(s)
Celulosa/análogos & derivados , Cimenos , Escherichia coli , Resinas de Plantas , Staphylococcus aureus , Embalaje de Alimentos
5.
J Phys Chem Lett ; 15(7): 2031-2038, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38349964

RESUMEN

Three-dimensional (3D) cationic lead halide hybrids constructed by organic ions and inorganic networks via coordination bonds are a promising material for solid-state lighting due to their exceptional environmental stability and broad-spectrum emission. Nevertheless, their fluorescence properties are hindered by the limited lattice distortion from extensive connectivity within the inorganic network. Here, a dramatic 100-fold enhancement of self-trapped exciton (STE) emission is achieved in 3D hybrid material [Pb2Br2][O2C(CH2)4CO2] via pressure-triggered phase transition. Notably, pressure-treated material exhibits a 110 nm redshift with 1.5-fold enhancement compared to the initial state after pressure was completely released. The irreversible structural phase transition intensifies the [PbBr3O3] octahedral distortion, which is highly responsible for the optimization of quenched emission. These findings present a promising strategy for improving the optical properties of 3D halide hybrids with relatively high stability and thus facilitate their practical applications by pressure-driven phase transition engineering.

6.
Small ; : e2311461, 2024 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-38386310

RESUMEN

PbS quantum dot (QD) solar cells harvest near-infrared solar radiation. Their conventional hole transport layer has limited hole collection efficiency due to energy level mismatch and poor film quality. Here, how to resolve these two issues by using Ag-doped PbS QDs are demonstrated. On the one hand, Ag doping relieves the compressive stress during layer deposition and thus improves film compactness and homogeneity to suppress leakage currents. On the other hand, Ag doping increases hole concentration, which aligns energy levels and increases hole mobility to boost hole collection. Increased hole concentration also broadens the depletion region of the active layer, decreasing interface charge accumulation and promoting carrier extraction efficiency. A champion power conversion efficiency of 12.42% is achieved by optimizing the hole transport layer in PbS QD solar cells, compared to 9.38% for control devices. Doping can be combined with compressive strain relief to optimize carrier concentration and energy levels in QDs, and even introduce other novel phenomena such as improved film quality.

7.
Lancet Rheumatol ; 6(1): e40-e50, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38258678

RESUMEN

BACKGROUND: Biosimilars provide an opportunity to address unmet medical need by expanding access to biological treatments. This study aimed to show equivalent efficacy, and comparable safety, immunogenicity, and pharmacokinetic profiles of a proposed tocilizumab biosimilar BAT1806/BIIB800, to reference tocilizumab, in participants with rheumatoid arthritis with an inadequate response to methotrexate. METHODS: This phase 3, multicentre, randomised, double-blind, active-controlled, equivalence study comprised a 24-week initial treatment period (results reported here) and a 24-week secondary treatment period. Participants were recruited at 54 centres across five countries (China, Ukraine, Poland, Georgia, and Bulgaria). Patients with active rheumatoid arthritis with an inadequate response to methotrexate were randomly assigned (1:1:2) to receive reference tocilizumab up to week 48, or reference tocilizumab up to week 24 followed by BAT1806/BIIB800 up to week 48 (the two reference tocilizumab groups were analysed as a single group in this analysis), or BAT1806/BIIB800 up to week 48 (the BAT1806/BIIB800 group), administered by intravenous infusion once every 4 weeks at a starting dose of 8 mg/kg. The primary endpoint was the proportion of participants who had a 20% improvement in American College of Rheumatology criteria (ACR20) at week 12 (for the European Medicines Agency [EMA]) or week 24 (for the US Food and Drug Administration [FDA] and China National Medical Products Administration [NMPA]) using prespecified equivalence margins (95% CI -14·5 to +14·5 [EMA], 90% CI -12·0 to +15·0 [FDA], and 95% CI -13·6 to +13·6 [NMPA]). The International Council for Harmonisation E9(R1) estimand framework, with strategies for addressing intercurrent events, was implemented for the efficacy evaluations with expected differences as per the predefined equivalence margins. This trial is registered at ClinicalTrials.gov (NCT03830203) and EudraCT (2018-002202-31), and is closed to new participants. FINDINGS: Between Dec 19, 2018, and Jan 5, 2021, we randomly assigned 621 participants: 309 to the reference tocilizumab group and 312 to the BAT1806/BIIB800 group. The mean age was 50·5 years (SD 12·0), 534 (86%) were women, 87 (14%) were men, and 368 (59%) were White. For the primary estimands, estimated ACR20 response rates were 64·8% in the reference tocilizumab group and 69·0% in the BAT1806/BIIB800 group (treatment difference 4·1% [95% CI -3·6 to 11·9]) at week 12, and 67·9% in the reference tocilizumab group and 69·9% in the BAT1806/BIIB800 group (treatment difference 1·9% [90% CI -4·0 to 7·9; 95% CI -5·2 to 9·1]) at week 24. All confidence intervals were contained within the predefined equivalence margins. Comparable pharmacokinetic and immunogenicity profiles were observed for the reference tocilizumab and BAT1806/BIIB800 groups. Adverse events were reported by 201 (65%) participants in the reference tocilizumab group and 206 (66%) in the BAT1806/BIIB800 group; 196 (63%) participants in the reference tocilizumab group and 201 (64%) participants in the BAT1806/BIIB800 group reported a treatment-emergent adverse event. Five participants had a fatal event (reference tocilizumab n=1; BAT1806/BIIB800 n=4). INTERPRETATION: BAT1806/BIIB800 showed equivalent efficacy, and comparable safety, immunogenicity, and pharmacokinetic profiles as reference tocilizumab. FUNDING: Bio-Thera Solutions and Biogen.


Asunto(s)
Amidas , Anticuerpos Monoclonales Humanizados , Artritis Reumatoide , Biosimilares Farmacéuticos , Propionatos , Masculino , Humanos , Femenino , Persona de Mediana Edad , Metotrexato/uso terapéutico , Biosimilares Farmacéuticos/efectos adversos , Artritis Reumatoide/tratamiento farmacológico , Método Doble Ciego
8.
Cancer Med ; 12(22): 20847-20863, 2023 11.
Artículo en Inglés | MEDLINE | ID: mdl-37935428

RESUMEN

BACKGROUND: BAT1706 is a proposed biosimilar of bevacizumab (Avastin®). We aimed to compare the efficacy and safety of BAT1706 with that of EU-sourced reference bevacizumab (EU-bevacizumab) in patients with advanced nonsquamous non-small cell lung cancer (NSCLC). METHODS: Patients were randomized 1:1 to BAT1706 plus paclitaxel and carboplatin (BAT1706 arm) or EU-bevacizumab plus paclitaxel and carboplatin (EU-bevacizumab arm) given every 3 weeks for six cycles, followed by maintenance therapy with BAT1706 or EU-bevacizumab. The primary endpoint was overall response rate at week 18 (ORR18 ). Clinical equivalence was demonstrated if the 90% confidence interval (CI) of the BAT1706:EU-bevacizumab ORR18 risk ratio was contained within the predefined equivalence margins of 0.75-1.33 (China National Medical Products Administration requirements), or 0.73-1.36 (US Food and Drug Administration), or if the 95% CI of the ORR18 risk difference between treatments was contained within the predefined equivalence margin of -0.12 to 0.15 (EMA requirements). RESULTS: In total, 649 randomized patients (BAT1706, n = 325; EU-bevacizumab, n = 324) received at least one cycle of combination treatment. The ORR18 was comparable between the BAT1706 and EU-bevacizumab arms (48.0% and 44.5%, respectively). The ORR18 risk ratio of 1.08 (90% CI: 0.94-1.24) and the ORR18 risk difference of 0.03 (95% CI: -0.04 to 0.11) were within the predefined equivalence margins, demonstrating the biosimilarity of BAT1706 and EU-bevacizumab. The safety profile of BAT1706 was consistent with that of EU-bevacizumab and no new safety signals were observed. CONCLUSION: In patients with advanced nonsquamous NSCLC, BAT1706 demonstrated clinical equivalence to EU-bevacizumab in terms of efficacy, safety, pharmacokinetics, and immunogenicity.


Asunto(s)
Biosimilares Farmacéuticos , Carcinoma de Pulmón de Células no Pequeñas , Neoplasias Pulmonares , Humanos , Protocolos de Quimioterapia Combinada Antineoplásica , Bevacizumab/efectos adversos , Biosimilares Farmacéuticos/efectos adversos , Carboplatino/uso terapéutico , Carcinoma de Pulmón de Células no Pequeñas/tratamiento farmacológico , Método Doble Ciego , Neoplasias Pulmonares/tratamiento farmacológico , Paclitaxel/uso terapéutico
9.
Sci Bull (Beijing) ; 68(11): 1153-1161, 2023 Jun 15.
Artículo en Inglés | MEDLINE | ID: mdl-37211491

RESUMEN

The miscibility between active layer donors (D) and acceptors (A) is a key factor impeding the development of organic photovoltaics (OPVs) toward higher performance and large-area production. In this study, melt blending crystallization (MBC) was used to accomplish molecular-level blending and highly oriented crystallization in bulk heterojunction (BHJ) films realized by a scalable blade coating process, which increased the D/A contact area and provided sufficient exciton diffusion and dissociation. At the same time, the highly organized and balanced crystalline nanodomain structures permitted dissociated carriers to be efficiently transmitted and collected, resulting in significantly enhanced short-circuit current density, fill factor, and efficiency of the device by means of optimum melting temperature and quenching rates. The method can be simply incorporated into current efficient OPV material systems and achieve a device performance comparable to the best values. The blade-coating-processed PM6/IT-4F MBC devices achieved an efficiency of 13.86% in a small-area device and 11.48% in a large-area device. A power conversion efficiency (PCE) of 17.17% was obtained in PM6:BTP-BO-4F devices, and a PCE of 16.14% was acquired in PM6:Y6 devices.


Asunto(s)
Películas Cinematográficas , Donantes de Tejidos , Humanos , Cristalización , Difusión , Temperatura
10.
Light Sci Appl ; 12(1): 85, 2023 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-37009810

RESUMEN

Solution-processed organic‒inorganic halide perovskite (OIHP) single crystals (SCs) have demonstrated great potential in ionizing radiation detection due to their outstanding charge transport properties and low-cost preparation. However, the energy resolution (ER) and stability of OIHP detectors still lag far behind those of melt-grown inorganic perovskite and commercial CdZnTe counterparts due to the absence of detector-grade high-quality OIHP SCs. Here, we reveal that the crystallinity and uniformity of OIHP SCs are drastically improved by relieving interfacial stress with a facial gel-confined solution growth strategy, thus enabling the direct preparation of large-area detector-grade SC wafers up to 4 cm with drastically suppressed electronic and ionic defects. The resultant radiation detectors show both a small dark current below 1 nA and excellent baseline stability of 4.0 × 10-8 nA cm-1 s-1 V-1, which are rarely realized in OIHP detectors. Consequently, a record high ER of 4.9% at 59.5 keV is achieved under a standard 241Am gamma-ray source with an ultralow operating bias of 5 V, representing the best gamma-ray spectroscopy performance among all solution-processed semiconductor radiation detectors ever reported.

11.
J Food Sci ; 88(6): 2496-2511, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37066847

RESUMEN

Red grapes (Vitis vinifera L.) have a high sugar content, thin skins, and relatively short shelf-life after harvesting. We developed polylactic acid/polybutylene succinate film, prepared by extrusion of polylactic acid and polybutylene succinate, that significantly prolonged the shelf-life of red grapes from 8 to 12 days by delaying the loss of weight, loss of hardness, and reduction in soluble solid content after harvesting. Further mechanistic study showed that this modified atmosphere film delayed the senescence of harvested red grape, the phenomenon that was highly related to the lower active oxygen species production and higher antioxidant enzyme activity compared to the non-packaged grape. The proposed continuous and dynamic microenvironment regulation system is a promising method to study the mechanisms of respiratory metabolism in fruit and extends food shelf-life while reducing food waste. PRACTICAL APPLICATION: In this study, we designed a means to microenvironmental regulatory packaging that directly creates a continuous, dynamic, and monitorable microenvironment. To ensure that the fruit inside the package underwent coordinated aerobic and anaerobic respiration, we melt-extruded polylactic acid (PLA) and polybutylene succinate (PBS) to form a homogeneous biodegradable film. We demonstrated that the best preservation results were achieved with a film comprising an 80/20 PLA-to-PBS ratio. This film can prolong the shelf-life of fruits by regulating respiratory metabolism.


Asunto(s)
Eliminación de Residuos , Vitis , Antioxidantes , Alimentos , Embalaje de Alimentos/métodos , Poliésteres , Frutas
12.
Int J Biol Macromol ; 235: 123716, 2023 Apr 30.
Artículo en Inglés | MEDLINE | ID: mdl-36801297

RESUMEN

Environmental and sustainability issues have received increasing attention in recent years. As a natural biopolymer, chitosan has been developed as a sustainable alternative to traditional chemicals such as food preservation, food processing, food packaging, and food additives due to its abundant functional groups and excellent biological functions. This review analyzes and summarizes the unique properties of chitosan, with a particular focus on the mechanism of action for its antibacterial and antioxidant properties. This provides a lot of information for the preparation and application of chitosan-based antibacterial and antioxidant composites. In addition, chitosan is modified by physical, chemical and biological modifications to obtain a variety of functionalized chitosan-based materials. The modification not only improves the physicochemical properties of chitosan, but also enables it to have different functions and effects, showing promising applications in multifunctional fields such as food processing, food packaging, and food ingredients. In the current review, applications, challenges, and future perspectives of functionalized chitosan in food will be discussed.


Asunto(s)
Quitosano , Quitosano/química , Antioxidantes/farmacología , Antibacterianos/farmacología , Embalaje de Alimentos , Alimentos
13.
Light Sci Appl ; 12(1): 8, 2023 Jan 02.
Artículo en Inglés | MEDLINE | ID: mdl-36588109

RESUMEN

The ionizing radiation possesses extremely strong penetration capability, which poses serious risk on the health of the human body and jeopardize electronics. Here the authors demonstrate that MAPbI3/epoxy composites prepared by a simple method show high radiation shielding performance.

14.
J Agric Food Chem ; 71(1): 905-919, 2023 Jan 11.
Artículo en Inglés | MEDLINE | ID: mdl-36548110

RESUMEN

A novel photodynamic inactivation (PDI)-mediated antimicrobial film of polylactic acid/5-aminolevulinic acid (PLA/ALA) was successfully fabricated by a covalent grafting method using low-temperature plasma. The chemical structure, surface morphology, hydrophilic ability, and mechanical and barrier properties of the films were characterized, and their antibacterial, anti-biofilm potency and preservation effects on ready-to-eat salmon were investigated during storage. Results showed that the amino group of ALA was covalently grafted with the carboxyl group on the surface of PLA after the plasma treatment, with the highest grafting rate reaching ∼50%. The fabricated PLA/ALA films displayed an enhanced barrier ability against water vapor and oxygen. Under blue light-emitting diode illumination, the PLA/ALA films generated massive reactive oxygen species from the endogenous porphyrins in cells induced by ALA and then fatally destroyed the cell wall of planktonic cells and the architectural structures of sessile biofilms of the pathogens (Listeria monocytogenes and Vibrio parahaemolyticus) and spoilage bacterium (Shewanella putrefaciens). More importantly, the PDI-mediated PLA/ALA films potently inhibited 99.9% native bacteria on ready-to-eat salmon and significantly suppressed the changes of its drip loss, pH, and lipid oxidation (MDA) during storage, and on this basis, the shelf life of salmon was extended by 4 days compared with that of the commercial polyethylene film. Therefore, the PDI-mediated PLA/ALA films are valid in inactivating harmful bacterial and preserving the quality of seafood.


Asunto(s)
Ácido Aminolevulínico , Salmón , Animales , Ácido Aminolevulínico/farmacología , Poliésteres/química , Alimentos Marinos/microbiología , Bacterias , Embalaje de Alimentos/métodos
15.
Nat Commun ; 13(1): 7874, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36550106

RESUMEN

Hybrid materials capitalize on the properties of individual materials to attain a specific combination of performance assets that is not available with the individual components alone. We describe a straightforward approach to preparation of sandwich-type hybrid dynamic materials that combine metals as electrically conductive components and polymers as bending, momentum-inducing components with flexible organic crystals as mechanically compliant and optically transducive medium. The resulting hybrid materials are conductive to both electricity and light, while they also respond to changes in temperature by deformation. Depending on the metal, their conductivity ranges from 7.9 to 21.0 S µm‒1. The elements respond rapidly to temperature by curling or uncurling in about 0.2 s, which in one typical case corresponds to exceedingly fast deformation and recovery rates of 2187.5° s‒1 and 1458.3° s‒1, respectively. In cyclic operation mode, their conductivity decreases less than 1% after 10,000 thermal cycles. The mechanothermal robustness and dual functionality favors these materials as candidates for a variety of applications in organic-based optics and electronics, and expands the prospects of application of organic crystals beyond the natural limits of their dynamic performance.

16.
J Phys Chem Lett ; 13(50): 11837-11843, 2022 Dec 22.
Artículo en Inglés | MEDLINE | ID: mdl-36520022

RESUMEN

Although seeking an effective strategy for further improving their optical properties is a great challenge, two-dimensional (2D) halide perovskites have attracted a significant amount of attention because of their performance. In this regard, the pressure-induced emission accompanied by a remarkable pressure-enhanced emission is achieved without a phase transition in 2D vacancy-ordered perovskite Cs3Bi2Cl9 nanocrystals (NCs). Note that the initial Cs3Bi2Cl9 NCs possess extremely strong electron-phonon coupling, leading to the easy annihilation of trapped excitons by the phonon. Upon compression, pressure could effectively suppress phonon-assisted nonradiative decay and give rise to an intriguing emission from "0" to "1". Both the weakened electron-phonon coupling and the relaxed halide octahedral distortion benefiting from the vacancy-ordered structure contributed to the subsequent enhanced emission. This work not only elucidates the underlying photophysical mechanism but also identifies pressure engineering as a robust means for improving their potential applications in environmentally friendly solid-state lighting at extremes.

17.
J Phys Chem Lett ; 13(29): 6792-6799, 2022 Jul 28.
Artículo en Inglés | MEDLINE | ID: mdl-35856791

RESUMEN

Halide perovskites are emerging as promising candidates for white light solid state lighting. Nevertheless, there are still challenges of a high water stability, a tunable color temperature, and a high photoluminescence quantum yield (PLQY). Herein, we report hydrophobic, electron-withdrawing trifluoromethyl (-CF3)-modified phenethylamine lead bromide (PEA2PbBr4) with ultrahigh stability in water for >2 months, and the broadband white light emission is illustrated by self-trapped excitons attributed to exciton-phonon coupling that coordinate molecular vibration, lattice distortion, and electrostatic interaction. In particular, by Mn2+ doping, the emission color can be tuned from cold (10237 K) to warm (2406 K), and a greatly enhanced PLQY of ≤87.93% can be achieved. Furthermore, the perovskites also possess an excellent color rendering index (the highest is 94). A monocomponent white light-emitting diode with amazing CIE 1931 coordinates of (0.33, 0.32) is further assembled, demonstrating a luminance of 471.5 cd m-2 at 50 mA and good long-term operation stability after >2 months. This study of highly efficient and stable perovskites with high-quality white light emission will open up new opportunities in solid state lighting.

18.
Adv Mater ; 34(32): e2203166, 2022 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-35724329

RESUMEN

A highly crystalline tempered-glass-like perovskite grain structure with compressed surface lattice realized by a thermal-shocking fabrication is shown. The strained perovskite grain structure is stabilized by Cl- -reinforcing surface lattice and shows enhanced bonding energy and ionic activation temperature, which contributes to hysteresis-free operation of perovskite solar cells (PSCs) at much higher temperature up to 363 K in thermal-shocking-processed MAPbClx I3- x (T-MPI). The PSCs can be fabricated by a high-speed fully air process without post-annealing based on the scalable bar-coating technique. Both high efficiency and stability are achieved in T-MPI PSC with a power conversion efficiency (PCE) up to 22.99% and long-term operational stability with T80 lifetime exceeding 4000 h.

19.
Small ; 18(24): e2201943, 2022 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-35570752

RESUMEN

Lead-free Cs2 AgBiBr6 double perovskite is considered to be a promising alternative to the traditional lead-based analogues due to its long carrier lifetime, high structural stability, and non-toxicity. However, the large band gap limits its absorption of visible light, which is not conducive to further optoelectronic applications. Herein, a thermochromic strategy is reported to decrease the band gap of Cs2 AgBiBr6 by approximately 0.36 eV, obtaining the smallest reported band gap of 1.69 eV under ambient conditions. The experimental data indicate that after annealing the Cs2 AgBiBr6 single crystals at 400 °C, the silver (Ag) and bismuth (Bi) atoms occupy the B-site in a random way and form a partially disordered configuration. The formation of the antisite defects broadens the band edges and decreases the band gap. This work offers new insights into the preparation of narrow band gap lead-free double perovskites, and a deep understanding of their structural and electronic properties for further development in photoelectric devices.

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