Monthly Archives: September 2023

Molecular engineering of inorganic halide perovskites and HTMs for photovoltaic applications

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Molecular engineering of inorganic halide perovskites and HTMs for photovoltaic applications

Theoretical analysis of V-J behavior demonstrated that the highest VOC and JSC related to LiPbF3 and KSnCl3, respectively.


Abstract

A comprehensive study was performed for the design of ABX3 perovskites, (A = Li, K, Na, B = Ge, Sn, Pb, X = F, Cl, Br, I) and organic hole transfer materials, HTMs (Fu-2a, Fu-2b, Fu-2c, and Dm-Q) for efficient perovskite solar cells (PSCs) through quantum chemistry calculations. Photovoltaic characteristics of the investigated perovskites are strongly affected by the halide anions. The results reveal that reducing the exciton binding energy of perovskites enhances the rate of the formation/dissociation of holes and electrons so F-based perovskites are superior from this viewpoint. Additionally, the electron and hole injection processes are more favorable in the case of the F-based perovskites in comparison with other studied perovskites. Moreover, spectroscopic properties of the perovskites demonstrate that KSnCl3, NaSnCl3, and F-based perovskites exhibit a greater ability of the light-harvesting and incident photon to current conversion efficiency. Ultimately, based on diverse analyses, F-based perovskites, KSnCl3 and NaSnCl3 are the preferred candidates to be applied in the PSCs due to an excellent incident photon to current conversion efficiency, light-harvesting efficiency, short circuit current, and solar cell final efficiency.

The performance of hybrid and F12∗$$ {}^{\ast } $$/F12c explicitly correlated coupled cluster methods for use in anharmonic vibrational frequency computations

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The performance of hybrid and F12∗$$ {}^{\ast } $$/F12c explicitly correlated coupled cluster methods for use in anharmonic vibrational frequency computations

The three components of the Taylor series approximation are computed via the F12-TcCR+$$ + $$DZ approach with the harmonics from F12-TcCR while the cubic and quartic terms are computed with F12-DZ. This method produces accurate results with relatively low computational cost.


Abstract

A hybrid quartic force field approach produces the same accuracies as non-hybrid methods but for less than one quarter of the computational time. This method utilizes explicitly correlated coupled cluster theory at the singles and doubles level inclusive of perturbative triples (CCSD(T)-F12b) in conjunction with a triple-ζ$$ \zeta $$ basis set, core electron correlation, and scalar relativity for the harmonic terms and CCSD(T)-F12b with a valence double-ζ$$ \zeta $$ basis set for the cubic and quartic terms. There is no sacrifice in the prediction of fundamental anharmonic vibrational frequencies or vibrationally-averaged rotational constants as compared to experiment, but the time saved is notable. Other hybrid methods are examined involving different sizes of basis sets and composite terms included or excluded. Not one is more accurate; only one is faster. F12∗$$ {}^{\ast } $$ (also called F12c) is tested as well, but it has an increase in computational time for no increase in accuracy. As such, this work reports a hybrid and composite approach (F12-TcCR+DZ) in the computation of rovibrational spectral data which can be applied to the observation of novel molecules in the gas phase in the laboratory and potentially even in astrophysical environments.

Cooperative Sensitization Upconversion in Ytterbium(III)‐Based Eosin Lake Pigments

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Cooperative Sensitization Upconversion in Ytterbium(III)-Based Eosin Lake Pigments

Reacting the eosin Y (EOS) dianion and ytterbium(III) in ethanol and under basic conditions afforded an EOS-Yb lake pigment able to transform low-energy photons, specifically near-infrared (NIR) photons, into higher energy photons. The process eventually lead to long-lived sensitized emission of the dye (microseconds) through cooperative sensitization (CS) upconversion.


Abstract

Materials based on organic chromophores and lanthanides able to transform low-energy photons, specifically near-infrared (NIR) photons, into higher energy photons to eventually lead to long-lived sensitized emission of the dye are highly desirable. Cooperative sensitization (CS) upconversion has only been accomplished for lanthanide-based clusters. We used here the eosin Y (EOS) dianion and Yb3+ (EOS-Yb), and demonstrate the efficient CS emission of the dye after NIR excitation. Remarkably, the EOS dianion emission exhibits a nearly linear dependence on the EOS-Yb concentration and a quadratic dependence on the laser power density. The emission is non-sensitive to oxygen and its lifetime lasts about 1.76 μs and 12 μs in DMSO and DMSO-d6 , respectively. Moreover, the effect of temperature (293–363 K range) on the EOS-Yb 1H NMR spectroscopic shifts demonstrates the reversible dynamic nature of the material.

Ligand‐Independent Activation of Aryl Hydrocarbon Receptor and Attenuation of Glutamine Levels by Natural Deep Eutectic Solvent

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Ligand-Independent Activation of Aryl Hydrocarbon Receptor and Attenuation of Glutamine Levels by Natural Deep Eutectic Solvent

A natural deep eutectic solvent, CAGE, derived from choline and geranic acid, perturb the metabolome, proteome, and transcriptome of human cell line. Specifically, CAGE upregulated 4-hydroxyphenyllactic acid and indole-3-lactic acid to activate the aryl hydrocarbon receptor, leading to the expression of IL1A, IL1B, CYP1A1, CYP1B1, ALDH31, NQO1. CAGE also attenuate the intracellular levels of glutamine.


Abstract

Natural deep eutectic solvents (NADESs) are emerging sustainable alternatives to conventional organic solvents. Beyond their role as laboratory solvents, NADESs are increasingly explored in drug delivery and as therapeutics. Their increasing applications notwithstanding, our understanding of how they interact with biomolecules at multiple levels - metabolome, proteome, and transcriptome - within human cell remain poor. Here, we deploy integrated metabolomics, proteomics, and transcriptomics to probe how NADESs perturb the molecular landscape of human cells. In a human cell line model, we found that an archetypal NADES derived from choline and geranic acid (CAGE) significantly altered the metabolome, proteome, and transcriptome. CAGE upregulated indole-3-lactic acid and 4-hydroxyphenyllactic acid levels, resulting in ligand-independent activation of aryl hydrocarbon receptor to signal the transcription of genes with implications for inflammation, immunomodulation, cell development, and chemical detoxification. Further, treating the cell line with CAGE downregulated glutamine biosynthesis, a nutrient rapidly proliferating cancer cells require. CAGE's ability to attenuate glutamine levels is potentially relevant for cancer treatment. These findings suggest that NADESs, even when derived from natural components like choline, can indirectly modulate cell biology at multiple levels, expanding their applications beyond chemistry to biomedicine and biotechnology.

[4.3.1]Bicyclic FKBP Ligands Inhibit Legionella Pneumophila Infection by LpMip‐Dependent and LpMip‐Independent Mechanisms

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[4.3.1]Bicyclic FKBP Ligands Inhibit Legionella Pneumophila Infection by LpMip-Dependent and LpMip-Independent Mechanisms**

In a screening of over 1000 FKBP-inhibitors [4.3.1]-bicyclic sulfonamides turned out to be the preferred binding scaffold for LpMip, a virulence factor of Legionella pneumophila. Although selected [4.3.1]-bicyclic sulfonamides showed anti-infective properties, LpMip was ruled out as sole target, with the results suggesting another FKBP is responsible for the observed effects.


Abstract

Legionella pneumophila is the causative agent of Legionnaires’ disease, a serious form of pneumonia. Its macrophage infectivity potentiator (Mip), a member of a highly conserved family of FK506-binding proteins (FKBPs), plays a major role in the proliferation of the gram-negative bacterium in host organisms. In this work, we test our library of >1000 FKBP-focused ligands for inhibition of LpMip. The [4.3.1]-bicyclic sulfonamide turned out as a highly preferred scaffold and provided the most potent LpMip inhibitors known so far. Selected compounds were non-toxic to human cells, displayed antibacterial activity and block bacterial proliferation in cellular infection-assays as well as infectivity in human lung tissue explants. The results confirm [4.3.1]-bicyclic sulfonamides as anti-legionellal agents, although their anti-infective properties cannot be explained by inhibition of LpMip alone.

Laser Interfaced Mass Spectrometry of the Sunscreen Molecule Octocrylene Demonstrates that Protonation Does Not Impact Photostability

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Laser Interfaced Mass Spectrometry of the Sunscreen Molecule Octocrylene Demonstrates that Protonation Does Not Impact Photostability

Laser photodissociation spectroscopy has been used to characterize the extent to which protonation affects the ability of octocrylene to act as an effective UV sunscreen molecule. We find that protonation results in a significant red shift of the absorption profile compared to non-protonated octocrylene, but does not impact on the ultrafast excited state decay pathways.


Abstract

Octocrylene (OCR) is a widely used organic sunscreen molecules, and is a dominant component of many sunscreen formulations. Here, we perform the first measurements on the protonated form of OCR, i. e. [OCR+H]+, to probe whether protonation affects the molecule's photostability. The novel photochemical technique of UV laser-interfaced mass spectrometry is employed from 400–216 nm, revealing that the electronic absorption spectrum of OCR across the S1 and S2 states red shift by 40 nm upon protonation. Our measurements reveal that [OCR+H]+ predominantly undergoes photofragmentation into the m/z 250 and 232 ionic products, associated with loss of its bulky alkyl side chain, and subsequent loss of water, respectively. We compare the photochemical fragmentation results with higher-energy collisional dissociation results to investigate the nature of the photodynamics that occur following UV absorption. The excited state decay pathways over the S1 and S2 excited states of [OCR+H]+ are associated with statistical fragmentation in line with dominant ultrafast decay. This behaviour mirrors that of neutral OCR, demonstrating that protonation does not affect the ultrafast decay pathways of this sunscreen molecule. We discuss our results in the context of the known breakdown of OCR into benzophenone, identifying a potential photoactivated pathway to benzophenone formation in solution.

Dual‐Responsive Drug‐Delivery System Based on PEG‐Functionalized Pillararenes Containing Disulfide and Amido Bonds for Cancer Theranostics

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Dual-Responsive Drug-Delivery System Based on PEG-Functionalized Pillararenes Containing Disulfide and Amido Bonds for Cancer Theranostics

A novel drug-delivery system with a dual response to GSH and enzymes is based on the newly designed PEG-functionalized pillararene for efficient and rapid drug release, and cancer therapy.


Abstract

The construction of a smart drug-delivery system based on amphiphilic pillararenes with multiple responsiveness properties has become an important way to improve the efficacy of tumor chemotherapy. Here, a new PEG-functionalized pillararene (EtP5-SS-PEG) containing disulfide and amido bonds was designed and synthesized, which has been used to construct a novel supramolecular nanocarrier through a host-guest interaction with a perylene diimide derivative (PDI-2NH4) and their supramolecular self-assembly. This nanocarrier showed good drug loading capability, and dual stimulus responsiveness to enzyme and GSH (glutathione). After loading of doxorubicin (DOX), the prepared nanodrugs displayed efficient DOX release and outstanding cancer theranostics ability.

Tightly Connected Poly(3‐Thiophene Boronic Acid)/g‐C3N4 Heterojunctions for Enhanced Visible‐Light Photocatalytic Hydrogen Production

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Tightly Connected Poly(3-Thiophene Boronic Acid)/g-C3N4 Heterojunctions for Enhanced Visible-Light Photocatalytic Hydrogen Production

Tightly connected poly(3-thiophene boronic acid)/g-C3N4 (PBTA/CN) heterojunctions were fabricated, dependent on hydrogen-bonding interactions for enhanced visible-light photocatalytic hydrogen production. The enhanced photoactivities are attributed to significantly enhanced charge transfer and separation by high-level electron transfer from CN to PTBA.


Abstract

Constructing efficient polymer semiconductor/g-C3N4 heterojunctions is highly desirable for enhancing the photogenerated charge separation of g-C3N4 and further improving the solar-hydrogen production efficiency. Herein, we synthesized poly(3-thiophene boronic acid)/g-C3N4 (PTBA/CN) heterojunctions with tight interface contact by a simple wet-chemical strategy. The resulting ratio-optimized 3PTBA/CN heterojunction exhibits 8.7 times enhancement of the visible-light photocatalytic hydrogen production compared to CN. Based on the steady-state surface photovoltage spectra (SS-SPS), photoluminescence spectra (PL), ⋅OH amount measurements, time-resolved photoluminescence spectra (TR-PL), and single-wavelength photocurrent action spectra, it is confirmed that the enhanced photocatalytic performance is mainly attributed to the promoted photogenerated charge separation resulting from the transfer of high-level electrons from CN to PTBA via the formed tight interface contact, depending on the hydrogen bonding interactions between the boronic acid groups [−B(OH)2] of PTBA and the amino groups (−NH2) of CN. Furthermore, the −B(OH)2 of PTBA facilitates the uniform dispersion of the co-catalyst Pt. This work provides an effective strategy for constructing efficient tightly connected polymer semiconductor/CN heterojunction photocatalysis.

Desilicated ZSM‐5 Catalysts: Properties and Ethanol to Aromatics (ETA) Performance

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Desilicated ZSM-5 Catalysts: Properties and Ethanol to Aromatics (ETA) Performance

Desilication is identified as valuable tool for increasing the lifetime of ZSM-5 catalysts used in the ethanol-to-aromatic conversion. A thorough solid-state NMR characterization enables disentangling the influence of changes in Si(OH) group density, Brønsted acidity, and mesopore volume on the catalyst's performance in terms of products and lifetime.


Abstract

Herein, desilication in increasingly harsh conditions was used to introduce mesopores into two different industrial ZSM-5 catalysts (Si/Al ratio 11 or 29). For desilicated samples, increasing BET surface areas, mesopore volumes, and Si(OH) densities were noted. Brønsted acid site (BAS) densities increased upon desilication, as formerly inaccessible BAS in blocked pores became available, while the strength of the BAS was maintained upon desilication. Using KOH instead of NaOH as desilication agent can increase the mesopore volume generated per mass loss. The correlations between desilication strength and properties were largely determined by the parent Si/Al ratio. In general the introduced mesopores increased lifetimes in the ETA conversion, while additional Si(OH) groups introduced by desilication reduce the lifetime again. The lifetime is thus determined by a complex interplay of BAS density, improved reactant transport by introduced mesopores and Si(OH) density. There were no additional aromatics formed in desilicated samples during the conversion of ethanol and the samples were, in terms of aromatic yield, outperformed by a microporous parent. However, as result of longer lifetimes less ethanol was lost due to coke formation. It is concluded that desilication should be combined with other post-modifications to increase aromatic production and lifetime.

Harnessing Nanomaterials for Enhanced Biohydrogen Generation from Wastewater

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Harnessing Nanomaterials for Enhanced Biohydrogen Generation from Wastewater

The present review describes an overview of the role of nanomaterials in biohydrogen production from wastewater.


Abstract

Biohydrogen is considered a green fuel due to its eco-friendly nature since it only produces water and energy on combustion. However, their lower yield and production rate is one of the foremost challenges that need an instant sustainable approach. The use of nanotechnology is a potential approach for the enhanced generation of biohydrogen, owing to the significant characteristics of the nanomaterials such as greater specificity, high surface-area-to-volume ratio, better reactivity and dispersibility, enhanced catalytic activity, superb selectivity, greater electron transfer, and better anaerobic microbiota activity. This article explores the recent trends and innovations in the production of biohydrogen from wastewater through the applications of different nanomaterials. The potential of various nanomaterials employed for biohydrogen production from wastewater is evaluated and the impacts of important parameters such as the concentration and size of the nanomaterials, temperature, and pH on the production and yield of biohydrogen are explained in detail. Several pathways involved in the mechanistic approach of biohydrogen generation from wastewater are critically assessed. Lastly, numerous technological challenges are highlighted and recommendations regarding future research are also provided.