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Postsynthetic exchange (PSE) of Ti(IV) into a Zr(IV)-based MOF enabled photocatalytic CO 2 reduction to HCOOH under visible light irradiation with the aid of BNAH and TEOA. Use of a mixedligand strategy enhanced the photocatalytic activity of the MOF by introducing new energy levels in the band structure of the MOF.
Metal–organic frameworks (MOFs) with isolated metal-monocatecholato groups have been synthesized via postsynthetic exchange (PSE) for CO 2 reduction photocatalyst under visible light irradiation in the presence of 1-benzyl-1,4-dihydronicotinamide and triethanolamine. The Cr-monocatecholato species are more efficient than the Ga-monocatecholato species
The glioblastoma (GBM) is characterized by a short median survival and an almost 100% tumor related mortality. GBM cells exhibit highly invasive behavior whose mechanisms are not yet fully understood. The present study explores application of X-ray and visible light microscopy to display the elemental and structural images of cells from 3 patient derived GMB samples and an established GMB cell line. Slight differences in elemental concentrations, in actin cytoskeleton organization and cell morphology were noted between all cells types by X-ray fluorescence and full field soft X-ray microscopy, as well as the Structured Illumination Super-resolution Microscope (SIM). Different sample preparation approaches were used to match each imaging technique. While preparation for SIM included cell fixation and staining, intact frozen hydrated cells were used for the trace element imaging by hard X-ray fluorescence and exploration of the structural features by soft X-ray absorption tomography. In conclusion, each technique documented differences between samples with regard to morphology and elemental composition and underscored the importance of use of multiple patient derived samples for detailed GBM study.
In this work, we present the postmodification of a diamondoid 3D supramolecular organic framework (SOF) to append [Ru(BPY) 3 ] 2+ groups through the formation of a hydrazone bond. The resulting SOF works as an efficient recyclable heterogeneous catalyst for visible-light-induced reduction of aromatic azides to amines.
A novel high-efficiency visible-light responsive Ag 4 (GeO 4 ) photocatalyst was prepared by a facile hydrothermal method. The photocatalytic activity of as-prepared Ag 4 (GeO 4 ) was evaluated by photodegradation of methylene blue (MB) dye and water splitting experiments. The photodegradation efficiency and oxygen production efficiency of Ag 4 (GeO 4 ) were detected to be 2.9 and 1.9 times higher than those of Ag 2 O. UVvis diffuse reflectance spectroscopy (DRS), photoluminescence experiment and photoelectric effect experiments prove that the good light response and high carrier separation efficiency facilitated by the internal electric field are the main reasons for Ag 4 (GeO 4 )'s excellent catalytic activity. Radical-trapping experiments reveal that the photogenerated holes are the main active species. Lastly, first-principles theoretical calculations provide more insight into understanding the photocatalytic mechanism of the Ag 4 (GeO 4 ) catalyst.
(GaN) 1–x (ZnO) x synthesized at high pressure produces H 2 in the presence of visible light without any cocatalysts or sacrificial reagents.
Divalent europium is used catalytically in visible-light-promoted photoredox bond-forming reactions.
Highly efficient saturation up-conversion (UC) luminescent Y2O3:Er3+ microspheres have been successfully prepared via a hydrothermal-homogeneous precipitation method. Bright visible luminescence can be clearly seen with a 1.55 mu m laser diode excitation power as low as similar to 0.03 W cm(-2). The up-conversion (UC) emission spectra indicate that the strongest red emission with a peak situated at similar to 660 nm originated from the I-4(9/2) -> I-4(15/2) transition of Er3+. The peaks situated at similar to 520 and 550 nm can be assigned to the transition from H-2(11/2)/S-4(3/2) state to the ground state of Er3+. The high efficient saturation up-conversion emission is related to the highly crystalline structure. These results indicate a new way to enhance UC radiation in rare-earth ion-doped materials prepared using a hydrothermal-homogeneous precipitation method.
Theory and experiment reveal relationships between observed UV-visible spectra and ion exchange site types, ion nuclearity, and finite-temperature dynamics in Cu exchanged chabazite (SSZ-13) zeolites.
Visible light active photocatalytic performance of g-C 3 N 4 /NSON-X heterojunctions.
A pore-expanded three-dimensional supramolecular organic framework SOF-bpb, with a previously unattained aperture size of 3.6 nm, has been constructed in water from the co-assembly of cucurbit[8]uril (CB[8]) and a tetraphenylmethane-cored 1,4-bis(pyridin-4-yl)-benzene-appended building block M1. The periodicity of SOF-bpb in water and in the solid state has been confirmed using synchrotron X-ray scattering and diffraction experiments. SOF-bpb can adsorb anionic and neutral Ru 2+ complex photosensitizers and anionic Wells–Dawson-type and Keggin-type polyoxometalates (POMs). The adsorption leads to an important enrichment effect, which remarkably increases the catalytic efficiency of the Ru 2+ complex–POM systems for visible light-induced reduction of protons to produce H 2 . Here, the expanded aperture of SOF-bpb also facilitates light absorption of the adsorbed Ru 2+ complex photosensitizers and electron transfer between excited complexes and the POM catalysts, leading to enhanced photocatalytic activities as compared with the prototypical SOF that has an aperture size of 2.1 nm.
K-region substituted pyrene-based MOFs for ROS generation upon direct visible-light irradiation.
Single unit process fabrication of a responsive Ag nanoparticle (NP) chemical hydrogel composite is achieved through digital visible light processing (DLP) 3D printing of a self-assembled nanostructured (multilamellar) resin doped with Ag( i ).
The mechanism of a visible light-driven dehalogenation/cyclization reaction was investigated using ruthenium(II), iridium(III) and iron(III) photosensitizers by means of steady-state photoluminescence, time-resolved infrared spectroscopy, and nanosecond/femtosecond transient absorption spectroscopy. The nature of the photosensitizer was found to influence the product distribution such that the dehalogenated, non-cyclized products were only detected for the iron photosensitizer. Strikingly, with the iron photosensitizer, large catalytic yields required a low dielectric solvent such as dichloromethane, consistent with a previous publication. This low dielectric solvent allowed ultrafast charge-separation to outcompete geminate charge recombination and improved cage escape efficiency. Finally, the identification of reaction mechanisms unique to the iron, ruthenium, and iridium photosensitizer represents progress towards the long-sought goal of utilizing earth-abundant, first-row transition metals for emerging energy and environmental applications.
We hereby engineered photoactivatable Pt( IV ) metallodrugs that harness CD36 to target ovarian cancer cells. Pt( IV ) compounds mimic the structure of fatty acids and take advantage of CD36 as a “Trojan horse” to gain entry into the cells. We confirmed that CD36-dependent entry occurs using graphite furnace atomic absorption spectroscopy with ovarian cancer cells expressing different levels of CD36 and a CD36 inhibitor, SSO. Once the Pt( IV ) metallodrugs enter the cancer cells, they can be activated to form Pt(II) with characteristics of cisplatin under visible light (490 nm) irradiation, promoting photoinduced electron transfer from the attached fluorophore to the metal center. Finally, this light-induced activation can increase the cytotoxicity of the Pt( IV ) metallodrugs by up to 20 times toward ovarian cancer cells, inducing DNA damage and enabling efficient elimination of drug-resistant cancer cells.
Triplet energy transfer from CdS quantum dots enhances europium( iii ) emission under visible light excitation.
It has been found recently that low-energy helium (He) plasma irradiation to tungsten (W) leads to the growth of W nanostructures on the surface. The process to grow the nanostructure is identified as a self-growth process of He bubbles and has a potential to open up a new plasma processing method. Here, we show that the metallic nanostructure formation process by the exposure to He plasma can occur in various metals such as, titanium, nickel, iron, and so on. When the irradiation conditions alter, the metallic cone arrays including nanobubbles inside are formed on the surface. Different from W cases, other processes than growth of fiberform structure, i.e., physical sputtering and the growth of large He bubbles, can be dominant on other metals during irradiation; various surface morphology changes can occur. The nanostructured W, part of which was oxidized, has revealed a significant photocatalytic activity under visible light (wavelength >700 nm) in decolorization of methylene blue without any co-catalyst.
A new wide-angle endoscope for visible light observation on the Experimental Advanced Superconducting Tokamak (EAST) has been recently developed. The head section of the optical system is based on a mirror reflection design that is similar to the International Thermonuclear Experimental Reactor-like wide-angle observation diagnostic on the Joint European Torus. However, the optical system design has been simplified and improved. As a result, the global transmittance of the system is as high as 79.6% in the wavelength range from 380 to 780 nm, and the spatial resolution is <5 mm for the full depth of field (4000 mm). The optical system also has a large relative aperture (1:2.4) and can be applied in high-speed camera diagnostics. As an important diagnostic tool, the optical system has been installed on the HT-7 (Hefei Tokamak-7) for its final experimental campaign, and the experiments confirmed that it can be applied to the investigation of transient processes in plasma, such as ELMy eruptions in H-mode, on EAST.