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In this work, we have shown that the introduction of a trifluoromethyl group into the me-ta-position of arylidene imidazolones (GFP chromophore core) leads to a dramatic increase in their fluorescence in nonpolar and aprotic media. The presence of a pronounced solvent-dependent gradation of fluorescence intensity makes it possible to use these substances as fluorescent polarity sensors. In particular, we showed that one of the created compounds could be used for selective labeling of the endoplasmic reticulum of living cells.

Lignin is the by-product of pulp and paper industries and bio-refining operations. It is available as the leading natural phenolic biopolymer in the market. It has chromophore functional groups and can absorb a broad spectrum of UV light in range of 250–400 nm. Using lignin as a natural ingredient in sunscreen cream, transparent film, paints, varnishes and microorganism protection has been actively investigated. Both in non-modified and modified forms, lignin provides enhancing UV protection of commercial products with less than a 10% blend with other material. In mixtures with other synthetic UV blockers, lignin indicated synergic effects and increased final UV blocking potential in compare with using only synthetic UV blocker or lignin. However, using lignin as a UV blocker is also challenging due to its complex structure, polydispersity in molecular weight, brownish color and some impurities that require more research in order to make it an ideal bio-based UV blocker.

Developing a mild and efficient method to simultaneously enhance poling efficiency and temporal stability is meaningful and challenging for organic second-order nonlinear optical materials. In this paper, a new poly (aryl ether ketone) and chromophores functionalized with anthracene groups have been designed and prepared. Poling and crosslinking process could be separated by the mild and photo-initiated cycloaddition of anthracene group. As the UV-Vis spectrum, DSC and TGA curves, the networks had formed by 30-min irradiation of the Lower-power UV light which led little decomposition of dipolar chromophores. The maximum electro-optic coefficient (r.sub.33) of these polymers is 28.5 pm V.sup.-1 (at 1.3 [mu]m), and the order parameter reaches 0.22. Moreover, the depolarization temperature of [alpha] peak, related to the dipole relaxation, has been increased to 129 °C after crosslinking, which is 17 °C higher than uncrosslinked ones. All these results indicated that the photo-crosslinking of anthracene exhibited promising potential for improving alignment stability and NLO activity at the same time.

Far-red phosphors featuring high quantum efficiency and emission bands that strongly overlap with the absorption spectra of plant pigments are crucial for advancing plant cultivation lighting technology. Restricted by the large Stokes shift, far-red phosphors typically exhibit low energy efficiency. Moreover, many far-red phosphors suffer from low quantum efficiency, which has emerged as a critical issue in the research of these materials. To address the issue, conventional strategies—including crystal field engineering, defect engineering, and sensitizer doping—have been widely adopted to enhance their emission intensity. In this work, we propose a novel and effective strategy to improve the emission performance of far-red phosphors: low-melting-point magnesium chloride has been introduced as a flux to regulate the reaction pathway of the composite oxide phosphor Ca[sub.14]Mg[sub.5.94]Li[sub.0.03]In[sub.0.03]Ga[sub.9.95]O[sub.35]:0.05Mn[sup.4+] (CMLIGO:0.05Mn[sup.4+]). The cubic intermediate product with a structure analogous to the target product has been designed to form a compact lattice structure and reduce crystal defects, thereby enhancing the luminescence intensity and quantum efficiency of the phosphor. The Ca[sub.14]Mg[sub.5.94]Li[sub.0.03]In[sub.0.03]Ga[sub.9.95]O[sub.35]:0.05Mn[sup.4+]@3 wt% MgCl[sub.2] (CMLIGO:0.05Mn[sup.4+]@3 wt% MgCl[sub.2]) shows a broad excitation band (250–600 nm) and far-red emission centered at 720 nm (650–800 nm). Under 365 nm excitation, the CMLIGO:0.05Mn[sup.4+]@3 wt% MgCl[sub.2] exhibits an internal quantum efficiency of 91.4%. Benefiting from its high internal quantum efficiency and the emission band that matches well with the absorption spectrum of phytochrome in the far-red absorbing form (phytochrome P[sub.fr]), CMLIGO:0.05Mn[sup.4+]@3 wt% MgCl[sub.2] demonstrates promising potential for applications in plant cultivation lighting. This work offers a new direction for synthesizing and modification of composite oxide phosphors.

The decomposition mechanism of dyes under the synergistic effect of pyroelectric catalysis and photocatalysis was systematically investigated using a BaTiO.sub.3/NiB catalyst in this paper, and the degradation efficiency of BaTiO.sub.3/NiB was 97.5% under light and 24 cycles of hot and cold at 25 65 °C, showing high pyroelectroic catalytic RhB decomposition activity and excellent recoverability. The degradation rate constants of RhB chromophore degradation by Pyro-photocatalytic coupled were 3.2 times as high as those of photocatalysis and 11.8 times as high as those of pyroelectric catalysis. In this study, we used light-assisted electrodeposition to deposit a thin layer of amorphous NiB acid salts onto the surface of a BaTiO.sub.3 photoelectrode aiming to explore its influence on photocharge separation and the catalytic mechanism of NiB in the context of pollutant degradation. The synergies between the pyroelectric internal field and the amorphous Ni-B acid salt thin layer during photogenerated charge separation were extensively explored in this paper, including the introduction of a port for pyroelectric polarization.

Microbial rhodopsins are photoreceptive membrane proteins that transport various ions using light energy. While they are widely used in optogenetics to optically control neuronal activity, rhodopsins that function with longer-wavelength light are highly demanded because of their low phototoxicity and high tissue penetration. Here, we achieve a 40-nm red-shift in the absorption wavelength of a sodium-pump rhodopsin (KR2) by altering dipole moment of residues around the retinal chromophore (KR2 P219T/S254A) without impairing its ion-transport activity. Structural differences in the chromophore of the red-shifted protein from that of the wildtype are observed by Fourier transform infrared spectroscopy. QM/MM models generated with an automated protocol show that the changes in the electrostatic interaction between protein and chromophore induced by the amino-acid replacements, lowered the energy gap between the ground and the first electronically excited state. Based on these insights, a natural sodium pump with red-shifted absorption is identified from Jannaschia seosinensis . Microbial rhodopsins are photoreceptive and widely used in optogenetics for which they should preferable function with longer-wavelength light. Here, authors achieve a 40-nm red-shift in the absorption wavelength of a sodium-pump rhodopsin (KR2) by altering the distribution of the retinal chromophore.

Photoexcited electron-hole pairs on a semiconductor surface can engage in redox reactions with two different substrates. Similar to conventional electrosynthesis, the primary redox intermediates afford only separate oxidized and reduced products or, more rarely, combine to one addition product. Here, we report that a stable organic semiconductor material, mesoporous graphitic carbon nitride (mpg-CN), can act as a visible-light photoredox catalyst to orchestrate oxidative and reductive interfacial electron transfers to two different substrates in a two- or three-component system for direct twofold carbon–hydrogen functionalization of arenes and heteroarenes. The mpg-CN catalyst tolerates reactive radicals and strong nucleophiles, is straightforwardly recoverable by simple centrifugation of reaction mixtures, and is reusable for at least four catalytic transformations with conserved activity.

Large language models (LLMs) have shown strong performance in tasks across domains but struggle with chemistry-related problems. These models also lack access to external knowledge sources, limiting their usefulness in scientific applications. We introduce ChemCrow, an LLM chemistry agent designed to accomplish tasks across organic synthesis, drug discovery and materials design. By integrating 18 expert-designed tools and using GPT-4 as the LLM, ChemCrow augments the LLM performance in chemistry, and new capabilities emerge. Our agent autonomously planned and executed the syntheses of an insect repellent and three organocatalysts and guided the discovery of a novel chromophore. Our evaluation, including both LLM and expert assessments, demonstrates ChemCrow’s effectiveness in automating a diverse set of chemical tasks. Our work not only aids expert chemists and lowers barriers for non-experts but also fosters scientific advancement by bridging the gap between experimental and computational chemistry. Large language models can be queried to perform chain-of-thought reasoning on text descriptions of data or computational tools, which can enable flexible and autonomous workflows. Bran et al. developed ChemCrow, a GPT-4-based agent that has access to computational chemistry tools and a robotic chemistry platform, which can autonomously solve tasks for designing or synthesizing chemicals such as drugs or materials.

Herein, first attempt has been made to utilize fluorene-based dye-sensitized solar cell (DSSCs) dye JK-201 as potential nonlinear optical (NLO) material and for the theoretical designing of novel NLO chromophores JK-D1–JK-D12. DFT/TDDFT calculations were performed to compute the effect of π-linkers and acceptors-steered modulation on electronic, photophysical and NLO properties of JK-201 and JK-D1–JK-D12. Results illustrate that computed λ max (484.74 nm) and experimentally calculated λ max (481 nm) of JK-201 was found in good agreement. Maximum red shifted absorption spectrum was observed in JK-D12 with 599.38 nm. JK-D1–JK-D12 showed narrow energy gap and broader absorption spectrum as compared to JK-201. NBO analysis confirmed the formation of charge separation state due to robust range of electrons/charge transfer from donor to acceptor via π-bridge. Giant NLO response was observed in all compounds. Particularly, JK-D12 displayed surprisingly large 〈 α 〉 and β tot computed 1376.74 (a.u.) and 405,731.84 (a.u.) respectively. Although literature is flooded with D–π–A compounds investigated for their DSSCs properties, but research reports on their NLO properties and utilization as NLO materials are completely deserted. Our research will open new horizons to explore DSSCs materials for NLO applications. This theoretical framework also exposed that fluorene-substituted chromophores are excellent NLO candidates for modern hi-tech applications. Graphical Abstract