- 标题
- 摘要
- 关键词
- 实验方案
- 产品
-
Strategies towards rational design of gold(iii) complexes for high-performance organic light-emitting devices
摘要： Gold(iii) complexes are attractive candidates as phosphorescent dopants in organic light-emitting devices for high-luminance full-colour displays. However, no data on the stability of such devices have been reported to date. Through rational molecular design and synthesis, we have successfully generated a new class of cyclometalated gold(iii) C^C^N complexes with tunable emission colours spanning from sky-blue to red. These complexes exhibit high photoluminescence quantum yields of up to 80% in solid-state thin films, excellent solubility and high thermal stability. Solution-processable and vacuum-deposited organic light-emitting devices based on these complexes operate with external quantum efficiencies of up to 11.9% and 21.6%, respectively, and operational half-lifetimes of up to 83,000 h at 100 cd m?2.
关键词： operational stability,phosphorescent dopants,organic light-emitting devices,cyclometalated,gold(iii) complexes,C^C^N complexes
更新于2025-11-19 16:56:35
-
Visible light-driven photoelectrocatalytic degradation of Acid Yellow 17 using Sn3O4 flower-like thin films supported on Ti substrate (Sn3O4/TiO2/Ti)
摘要： This article reports a new method for preparing mixed valence tin oxide (Sn3O4) flower-like nanostructures using a microwave-assisted route. Thin-film Sn3O4/TiO2/Ti electrodes demonstrated highly efficient visible light driven photocatalytic degradation of monoazo acid yellow 17 (AY17) dye, reaching 95% color removal after 60 min at pH 2. Moreover, under low bias potential (0.5 V), the photoelectrocatalytic efficiency increased to 97% color removal and 83% removal of total organic carbon at a kinetic rate almost 3 times higher than in photocatalysis. Liquid chromatography mass spectrometry was used to identify intermediate formation, and oxidation performance was proposed for photocatalytic and photoelectrocatalytic degradation with no organics identified after 120 min of treatment. The results indicate that Sn3O4/TiO2/Ti photoelectrodes offer a simple, green method for wastewater treatment employing visible light source.
关键词： Dye degradation,Photoelectrocatalysis,Microwave-assisted hydrothermal synthesis,Sn3O4,Visible-light photocatalysis
更新于2025-11-19 16:56:35
-
Synthesis, Photophysical and Electroluminescent Properties of Iridium(III) Complexes with 2-Aryl-thiazole and Oxadiazol-substituted Amide Derivative Ligands
摘要： By using aryl-thiazole as cyclometalated ligand and oxadiazol-substituted amide as ancillary ligand, three novel iridium(III) complexes have been synthesized and characterized, and the photophysical and electrochemical properties have been investigated. Complexes 1–3 exhibit efficient phosphorescence emissions at 542, 555 and 585 nm with photoluminescence quantum yields (PLQYs) of 0.04, 0.03 and 0.02 in CH3CN solutions, respectively. In the 10 wt% doped 2,4-diphenyl-6-bis(12-phenylindolo)[2,3-a]carbazole-11-yl)-1,3,5-triazine (Dictrz) film, the PLQYs (0.88 for complex 1, 0.47 for complex 2 and 0.37 for complex 3) increase significantly owing to the great restriction of rotations and vibrations in rigid host. The organic light-emitting diodes based on these complexes show good performance with the maximum current efficiencies of 20.06, 22.20 and 13.45 cd A-1 and maximum power efficiencies of 13.54, 17.31 and 9.48 lm W?1 with the CIE coordinates of (0.46, 0.53), (0.49, 0.50) and (0.59, 0.40) for complexes 1?3, respectively.
关键词： Iridium complex,Aryl-thiazole,Organic light-emitting diodes,Oxadiazol-substituted amide
更新于2025-11-19 16:56:35
-
Cationic porphyrins with large side arm substituents as resonance light scattering ratiometric probes for specific recognition of nucleic acid G-quadruplexes
摘要： Specific G-quadruplex-probing is crucial for both biological sciences and biosensing applications. Most reported probes are focused on fluorescent or colorimetric recognition of G-quadruplexes. Herein, for the first time, we reported a new specific G-quadruplex-probing technique—resonance light scattering (RLS)-based ratiometric recognition. To achieve the RLS probing of G-quadruplexes in the important physiological pH range of 7.4-6.0, four water soluble cationic porphyrin derivatives, including an unreported octa-cationic porphyrin, with large side arm substituents were synthesized and developed as RLS probes. These RLS probes were demonstrated to work well for ratiometric recognition of G-quadruplexes with high specificity against single- and double-stranded DNAs, including long double-stranded ones. The working mechanism was speculated to be based on the RLS signal changes caused by porphyrin protonation that was promoted by the end-stacking of porphyrins on G-quadruplexes. This work adds an important member in G-quadruplex probe family, thus providing a useful tool for studies on G-quadruplex-related events concerning G-quadruplex formation, destruction and changes in size, shape and aggregation. As a proof-of-concept example of applications, the RLS probes were demonstrated to work well for label-free and sequence-specific sensing of microRNA. This work also provides a simple and useful way for the preparation of cationic porphyrins with high charges.
关键词： G-quadruplex,ratiometric recognition,microRNA sensing,resonance light scattering,cationic porphyrin
更新于2025-11-19 16:56:35
-
Synergistic Effects of Photo-Irradiation and Curcumin-Chitosan/Alginate Nanoparticles on Tumor Necrosis Factor-Alpha-Induced Psoriasis-Like Proliferation of Keratinocytes
摘要： Psoriasis is a chronic inflammatory skin disease characterized by hyperproliferation of the epidermal cells and is clinically presented as thick, bright red to pink plaques with a silvery scale. Photodynamic therapy (PDT) using visible light has become of increasing interest in the treatment of inflammatory skin diseases. In this study, we demonstrate that a combination of curcumin-loaded chitosan/alginate nanoparticles (Cur-CS/Alg NPs) and blue light emitting diodes (LED) light irradiation effectively suppressed the hyperproliferation of tumor necrosis factor-alpha (TNF-α)-induced cultured human kerlatinocyte (HaCaT) cells. The Cur-CS/Alg NPs were fabricated by emulsification of curcumin in aqueous sodium alginate solution and ionotropic gelation with calcium chloride and chitosan using an optimized formulation derived from a Box-Behnken design. The fabricated Cur-CS/Alg NPs were characterized for their particle size, zeta potential, encapsulation efficiency, and loading capacity. The surrogate 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay, to measure the relative number of viable cells, showed that the CS/Alg NPs were nontoxic to normal HaCaT cells, while 0.05 μg/mL and 0.1 μg/mL of free curcumin and Cur-CS/Alg NPs inhibited the hyperproliferation of HaCaT cells induced by TNF-α. However, the Cur-CS/Alg NPs demonstrated a stronger effect than the free curcumin, especially when combined with blue light irradiation (10 J/cm2) from an LED-based illumination device. Therefore, the Cur-CS/Alg NPs with blue LED light could be potentially developed into an effective PDT system for the treatment of psoriasis.
关键词： LED light,chitosan/alginate nanoparticles,curcumin,photo-irradiation,psoriasis
更新于2025-11-19 16:56:35
-
A novel photocatalyst, Y2SiO5:Pr3+,Li/Pt-NaNbxTa1?xO3, for highly efficient photocatalytic hydrogen evolution under visible-light irradiation
摘要： In this work, Y2SiO5:Pr3+,Li, as an excellent up-conversion luminescence agent from visible-light to ultraviolet-light, is synthesized by using sol-gel method. And then, a series of Y2SiO5:Pr3+,Li/NaNbxTa1?xO3 (x = 0.00, 0.25 and 0.50) with different amounts of Y2SiO5:Pr3+,Li are prepared by using hydrothermal method. The prepared samples are characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), X-ray photoelectron spectroscopy (XPS), UV–vis absorption spectroscopy and photoluminescence spectroscopy (PL). The activities of Y2SiO5:Pr3+,Li/Pt-NaNbxTa1?xO3 are investigated through photocatalytic hydrogen evolution in 10 vol% methanol solution under visible-light irradiation. The influences of Nb content in NaNbxTa1?xO3, mass ratio of Y2SiO5:Pr3+,Li and NaNb0.5Ta0.5O3, visible-light irradiation time and reuse-times are examined on the visible-light photocatalytic hydrogen evolution. The experimental results showed that the prepared Y2SiO5:Pr3+,Li/Pt-NaNb0.5Ta0.5O3 with 0.4:1.0 mass ratio of Y2SiO5:Pr3+,Li and NaNb0.5Ta0.5O3 and 0.25 wt% Pt loading displayed a highest evolved hydrogen activity under visible-light irradiation. This study may provide some significant references for large scale photocatalytic hydrogen evolution utilizing solar energy.
关键词： Visible-light photocatalyst (Y2SiO5:Pr3+,Li/Pt-NaNb0.5Ta0.5O3),Photocatalytic hydrogen evolution,Pt loading,Nb-substituted NaTaO3,Up-conversion luminescence agent (Y2SiO5:Pr3+,Li)
更新于2025-11-19 16:51:07
-
Effects of annealing conditions on the oxygen evolution activity of a BaTaO2N photocatalyst loaded with cobalt species
摘要： Precise engineering of the cocatalyst-photocatalyst interface and optimization of the cocatalyst dispersion are essential for improving the activity of particulate semiconductor photocatalysts. Herein, we report the effects of varying the conditions used to load cobalt oxide (CoOx) as a cocatalyst on the O2 evolution activity of a particulate BaTaO2N photocatalyst, based on trials in an aqueous silver nitrate solution under visible light irradiation. Annealing under an N2 flow after loading the Co species increased the O2 evolution rate threefold compared to that obtained following conventional annealing under an NH3 flow. Subsequent annealing under an H2 atmosphere exposed the BaTaO2N surface as a result of the aggregation of CoOx particles, and further enhanced the photocatalytic O2 evolution by a factor of two, yielding an apparent quantum efficiency of 0.55% at 420 nm. These results indicate the importance of intimate contact between cocatalyst particles and the photocatalyst, as well as the necessity of exposing the photocatalyst surface to make it available for reduction reactions during photocatalytic water oxidation.
关键词： Cocatalyst,Dispersion,Oxynitride,Visible light
更新于2025-11-19 16:51:07
-
Lewis acid activated CO <sub/>2</sub> reduction over a Ni modified Ni–Ge hydroxide driven by visible-infrared light
摘要： Improvement of light harvesting and reaction kinetics is of great importance for achieving efficient solar-driven CO2 reduction. Here, a Ni modified low-crystalline Ni–Ge containing hydroxide with Lewis acid sites was synthesized in highly reductive NaBH4 solution and exhibited 9.3 μmol gcat.?1 h?1 CO and 3.5 μmol gcat.?1 h?1 CH4 generation rates under visible light irradiation, and even achieved a 3.8 μmol gcat.?1 h?1 CO evolution under infrared light irradiation. The wide-spectrum light harvesting resulted from the light absorption from the localized surface plasmonic resonance of Ni nanoparticles. In addition, the Lewis acid can activate CvO bonds to decrease the kinetic barriers of CO2 reduction. The design concept that rationally combines the advantages of expanding the spectral response and activating CO2 may offer a new strategy for efficient solar energy utilization.
关键词： visible-infrared light,plasmonic effect,Lewis acid,CO2 reduction,photocatalyst
更新于2025-11-19 16:51:07
-
Distinguishing the effects of altered morphology and size on visible-light-induced water oxidation activity and photoelectrochemical performance of BaTaO2N crystal structures
摘要： Factors, including crystallinity, morphology, size, preferential orientation, growth, composition, porosity, surface area, etc., can directly influence the optical, charge-separation, charge-transfer and water oxidation and reduction properties of particle-based photocatalysts. Therefore, these factors must be considered when designing high-performance particle-based photocatalysts for solar water splitting. Here, a flux growth method was applied to alter the morphology and size of the Ba5Ta4O15 precursor oxide crystals using BaCl2, KCl, RbCl, CsCl, KCl+BaCl2 and K2SO4 at different solute concentrations, and the impact of nitridation with and without KCl flux was studied. Specifically, the effects of altered morphology and size on the visible-light-induced water oxidation activity and photoelectrochemical performance of the BaTaO2N crystal structures were investigated. Upon nitridation, the samples became porous due to the lattice shrinkage caused by the replacement of 3 O2? with 2 N3? in the anionic network. The BaTaO2N crystal structures obtained by nitridation without KCl flux show higher surface areas than do their counterparts prepared by nitridation with KCl flux because of the formation of porous networks. All samples exhibited a high anodic photocurrent upon nitridation without KCl flux compared with that of the samples obtained by nitridation with KCl flux. The findings demonstrate that it is important to specifically engineer photocatalytic crystals to reach their maximum potential in solar water splitting.
关键词： Water splitting,Visible light,Flux growth,Crystal size,Morphology,BaTaO2N
更新于2025-11-19 16:51:07
-
Effect of conduction band potential on cocatalyst-free plasmonic H <sub/>2</sub> evolution over Au loaded on Sr <sup>2+</sup> -doped CeO <sub/>2</sub>
摘要： There is little information on the effect of the conduction band (CB) position on plasmonic hydrogen (H2) formation under visible light irradiation over gold (Au) nanoparticles supported on semiconductors because there were no appropriate materials for which the CB position gradually changes. In this study, we analyzed the flatband potential of strontium ion (Sr2+)-doped cerium(IV) oxide (CeO2:Sr) and found that the CB position gradually shifted negatively from +0.031 V to ?1.49 V vs. NHE with an increase in the Sr2+ mole fraction. Plasmonic photocatalysts consisting of Au nanoparticles, CeO2:Sr and a platinum (Pt) cocatalyst were prepared and characterized by using X-ray diffraction, UV-vis spectroscopy, and transmission electron spectroscopy. Photocatalytic reaction under visible light irradiation revealed that H2 was produced over Au nanoparticles supported on CeO2:Sr having the CB potential of ?0.61 V vs. NHE and that the negative limit of the CB position for electron injection from Au nanoparticles existed between ?0.61 V and ?1.49 V vs. NHE. We found that Au/CeO2:Sr plasmonic photocatalysts also produced H2 without the aid of a Pt cocatalyst due to the sufficiently negative potential of electrons injected into the CB of CeO2:Sr.
关键词： hydrogen evolution,visible light irradiation,gold nanoparticles,plasmonic photocatalysts,strontium-doped cerium oxide
更新于2025-11-19 16:51:07