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1.
J Craniofac Surg ; 2024 May 23.
Artículo en Inglés | MEDLINE | ID: mdl-38781430

RESUMEN

Overmature cataract refers to the advanced stage of cataract where timely surgical intervention is not performed, leading to further progression characterized by decreased water content in the lens, degradation of fibers, and liquefaction within its structure, which can cause a reduction in volume, wrinkling of the capsule, as well as calcification or cholesterol crystallization on its surface. In addition, it may result in deepening of the anterior chamber. If left promptly untreated, these complications may result in visual impairment or even blindness. The occurrence of spontaneous complete dislocation of the lens nucleus into the anterior chamber in overmature cataracts is extremely uncommon. The authors present a case study involving a 74-year-old female patient who was diagnosed with complete dislocation of the lens nucleus in an overmature senile cataract without any apparent ocular injury or any relevant medical records. After undergoing cataract removal combined with anterior vitrectomy, the patient experienced relief from eye discomfort and expressed satisfaction with the surgical outcome; however, her visual acuity did not show significant improvement.

2.
J Chem Phys ; 160(12)2024 Mar 28.
Artículo en Inglés | MEDLINE | ID: mdl-38533888

RESUMEN

Hot carrier solar cells could offer a solution to achieve high efficiency solar cells. Due to the hot-phonon bottleneck in perovskites, the hot carrier lifetime could reach hundreds of ps. Such that exploring perovskites could be a good way to promote hot carrier technology. With the incorporation of large organic cations, the hot carrier lifetime can be improved. By using ultrafast transient spectroscopy, the hot carrier relaxation and extraction kinetics are measured. From the transient kinetics, 2-phenyl-acetamidine cation based perovskites exhibit the highest initial carrier temperature, longest carrier relaxation, and slowest hot carrier relaxation. Such superior behavior could be attributed to reduced electron-phonon coupling induced by lattice strain, which is a result of the large organic cation and also a possible surface electronic state change. Our discovery exhibits the potential to use large organic cations for the use of hot carrier perovskite solar cells.

3.
Nat Commun ; 15(1): 2579, 2024 Mar 22.
Artículo en Inglés | MEDLINE | ID: mdl-38519495

RESUMEN

Perovskite photovoltaics, typically based on a solution-processed perovskite layer with a film thickness of a few hundred nanometres, have emerged as a leading thin-film photovoltaic technology. Nevertheless, many critical issues pose challenges to its commercialization progress, including industrial compatibility, stability, scalability and reliability. A thicker perovskite film on a scale of micrometres could mitigate these issues. However, the efficiencies of thick-film perovskite cells lag behind those with nanometre film thickness. With the mechanism remaining elusive, the community has long been under the impression that the limiting factor lies in the short carrier lifetime as a result of defects. Here, by constructing a perovskite system with extraordinarily long carrier lifetime, we rule out the restrictions of carrier lifetime on the device performance. Through this, we unveil the critical role of the ignored lattice strain in thick films. Our results provide insights into the factors limiting the performance of thick-film perovskite devices.

4.
Adv Mater ; 36(8): e2307422, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38037894

RESUMEN

In two-dimensional/three-dimensional (2D/3D) perovskite heterostructure, randomly distributed multiple quantum wells (QW) 2D perovskites are frequently generated, which are detrimental to carrier transport and structural stability. Here, the high quality 2D/3D perovskite heterostructure is constructed by fabricating functional-group-induced single QW Dion-Jacobson (DJ) 2D perovskites. The utilization of ─OCH3 in the precursor solution facilitates the formation of colloidal particles with uniform size, resulting in the production of a pure 2D DJ perovskite with an n value of 3. This strategy facilitates the improvement of 3D structural stability and expedites carrier transport. The resultant devices accomplish a power conversion efficiency of 25.26% (certified 25.04%) and 23.56% at a larger area (1 cm2 ) with negligible hysteresis. The devices maintain >96% and >89% of their initial efficiency after continuous maximum power point tracking under simulated AM1.5 illumination for 1300 h and under damp-heat conditions (85 °C and 85% RH) for 1010 h, respectively.

5.
ACS Appl Mater Interfaces ; 15(36): 42611-42621, 2023 Sep 13.
Artículo en Inglés | MEDLINE | ID: mdl-37643590

RESUMEN

Solar-driven photocatalysis is a promising approach for renewable energy application. H2O2 photocatalysis by metal-free graphitic carbon nitride has been gaining attention. Compared with traditional thermal catalysis, metal-free graphitic carbon nitride photocatalysis could lower material cost and achieve greener production of H2O2. Also, to better guide photocatalyst design, a fundamental understanding of the reaction mechanism is needed. Here, we develop a series of model cost-effective metal-free H2O2 photocatalysts made from graphitic carbon nitride (melem) and common imide groups. With 4,4'-oxydiphthalic anhydride (ODPA)-modified g-C3N4, a H2O2 yield rate of 10781 µmol/h·g·L could be achieved. Transient absorption and ex situ Fourier transform infrared (FTIR) measurements revealed an ultrafast charge transfer from the melem core to water with ∼3 ps to form unique N-OH intermediates. The electron withdrawing ability of the anhydride group plays a role in governing the rate of electron transfer, ensuring efficient charge separation. Our strategy represents a new way to achieve a low material cost, simple synthesizing strategy, good environment impact, and high H2O2 production for renewable energy application.

6.
Adv Mater ; 35(23): e2301028, 2023 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-37026996

RESUMEN

Interfacial nonradiative recombination loss is a huge barrier to advance the photovoltaic performance. Here, one effective interfacial defect and carrier dynamics management strategy by synergistic modulation of functional groups and spatial conformation of ammonium salt molecules is proposed. The surface treatment with 3-ammonium propionic acid iodide (3-APAI) does not form 2D perovskite passivation layer while the propylammonium ions and 5-aminopentanoic acid hydroiodide post-treatment lead to the formation of 2D perovskite passivation layers. Due to appropriate alkyl chain length, theoretical and experimental results manifest that COOH and NH3 + groups in 3-APAI molecules can form coordination bonding with undercoordinated Pb2+ and ionic bonding and hydrogen bonding with octahedron PbI6 4- , respectively, which makes both groups be simultaneously firmly anchored on the surface of perovskite films. This will strengthen defect passivation effect and improve interfacial carrier transport and transfer. The synergistic effect of functional groups and spatial conformation confers 3-APAI better defect passivation effect than 2D perovskite layers. The 3-APAI-modified device based on vacuum flash technology achieves an alluring peak efficiency of 24.72% (certified 23.68%), which is among highly efficient devices fabricated without antisolvents. Furthermore, the encapsulated 3-APAI-modified device degrades by less than 4% after 1400 h of continuous one sun illumination.

7.
Small ; 19(14): e2205720, 2023 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-36634983

RESUMEN

Nanoporous single-crystal silicon carbide (SiC) is widely used in various applications such as protein dialysis, as a catalyst support, and in photoanodes for photoelectrochemical water splitting. However, the fabrication of nano-structured SiC is challenging owing to its extreme chemical and mechanical stability. This study demonstrates a highly-efficient, open-circuit electrolytic plasma-assisted chemical etching (EPACE) method without aggressive fluorine-containing reactants. The EPACE method enables the nano-structuring of SiC via a plasma-enveloped microtool traversing over the target material in an electrolyte bath. Through process design, EPACE readily produces a uniform nanoporous layer on a 4H-SiC wafer in KOH aqueous solution, with adjustable pore diameters in the range 40-130 nm. Plasma diagnosis by optical emission spectrometry (OES) and surface microanalysis reveal that EPACE realizes a nanoporous structure by electrolytic plasma-assisted oxidation and subsequent thermochemical reduction of an oxide. An increase in voltage or a decrease in etch gap intensifies the plasma and improves the etching efficiency. The maximum etch rate and depth reach 540 nm min-1 and 10 µm, respectively, demonstrating the significant potential of the approach as a time-saving and sustainable nanofabrication method for industrial applications. Further, the effectiveness of the fabricated SiC nanoporous structure for application in photoelectrochemical water splitting is demonstrated.

8.
Nanoscale ; 13(43): 18044-18053, 2021 Nov 11.
Artículo en Inglés | MEDLINE | ID: mdl-34718365

RESUMEN

Solar energy conversions play a vital role in the renewable energy industry. In recent years, photoredox organic transformations have been explored as an alternative way to use solar energy. Catalysts for such photocatalytic systems have evolved from homogeneous metal complexes to heterogeneous nanomaterials over the past few decades. Herein, three important carrier transfer mechanisms are presented, including charge transfer, energy transfer and hot carrier transfer. Several models established by researchers to understand the catalytic reaction mechanisms are also illustrated, which promote the reaction system design based on theoretical studies. New strategies are introduced in order to enhance catalytic efficiency for future prospects.

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