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Monthly Archives: March 2024
FT-IR studies and excess thermodynamic properties of binary mixtures at various temperatures and correlation with the Jouyban–Acree model
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Determination of experimental solute descriptor values for safrole by liquid-liquid partitioning and gas chromatography
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Theoretical Identification on Typical Fe3X (X=B, C, N) Compounds for Polysulfide Conversion in Lithium‐Sulfur Batteries
Li-S batteries (LSBs) are considered as the attractive candidates for next-generation high-energy system due to their high energy and low cost. However, their practical application is hindered by several stubborn issues, including the poor electric conductivity of sulfur cathodes, the shuttle of lithium polysulfides (LiPSs) and the slow dynamics during charge/discharge cycles. Transitional iron (Fe)-based compounds are regarded as effectively electrocatalysts for polysulfide conversion by accelerating the reaction kinetics and enhancing the electric conductivity electron/charge transfer. In this study, we investigate the typical transition Fe-based compounds (Fe3X, X = B, C, N) known for their high catalytic ability and analyze their roles as sulfur host for LSBs using density functional theory (DFT). Our finding reveal that Fe3C and Fe3B surfaces exhibit more Fe-S bonds compared to Fe3N surface, which explains the different electrochemical behaviors observed during battery testing with sulfur cathode. Additionally, Fe3N demonstrates greater structural stability and effective polysulfide adsorption according to DFT calculations, outperforming the other two compounds in these aspects. We believe that this theoretical investigation will guide the identification of highly efficient hosts for sulfur cathodes and open new avenues for sulfur host selection in LSBs.
Synthesis, characterization and anticancer screening of novel phenylbenzylidene thiosemicarbazone derivatives
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Diborane, Diborene and M(I)‐η2‐Diborene Complexes Stabilized by Bicyclic (Alkyl)(Amino)Carbene (M = Cu and Ag)
BICAAC (bicyclic (alkyl)(amino)carbene) as ambiphilic carbene has been utilized to prepare stable neutral tetrahydrodiborane [BICAAC→(H2)B-B(H2)←BICAAC] and dihydrodiborene [BICAAC→(H)B=B(H)←BICAAC] compounds. The Lewis base stabilized dihydrodiborene is isoelectronic and isolobal to conventional olefins and therefore offers the possibility to explore the formation of π-complexes with transition metals. Reaction of the diborene with coinage metal salts (CuCl, AgBr and CuI) leads to the formation of π-diborene metal complexes via η2 side-on coordination. These are first examples of dihydrodiborene coinage metal complexes. Interestingly, coordination of two CuCl units to the diborene has been observed for the first time with a considerable lengthening of >B=B< and B-CBICAAC bonds manifesting the key role of the BICAAC combined with small steric requirements of hydride substituents in stabilizing these complexes. The energy decomposition analysis (EDA) calculations reveal the interaction between the diborene and Cu(I)/Ag(I) is mainly electrostatic in nature.
Exploring the potential of microbial biomass and microbial extracted oils in tribology: a sustainable frontier for environmentally acceptable lubricants
Triethyl phosphate (TEP) as a green solvent for solid-phase peptide synthesis (SPPS)
Multi‐Resonance Thermally Activated Delayed Fluorescence Molecules for Triplet‐Triplet Annihilation Upconversion
Triplet-triplet annihilation upconversion (TTA-UC) has made significant progress in recent years in several key applications, including solar energy harvesting, photocatalysis, stereoscopic 3D printing, and disease therapeutics. In TTA-UC research, photosensitizers serve the vital function of harvesting low-energy photons. The photophysical characteristics of photosensitizers, including absorbance, triplet state quantum yield, triplet state energy level, triplet state lifetime, etc., determine the performance of TTA-UC. Thus, the study of photosensitizers has been a key aspect of TTA-UC. In recent years, multi-resonance thermally activated delayed fluorescence (MR-TADF) molecules have received extensive attention due to their excellent photophysical properties and electroluminescent device performance. MR-TADF molecules not only present a narrow energy gap between the singlet and triplet excited states, but also have stronger absorption and better wavelength regulation than conventional TADF molecules. Nowadays, the preliminary attempts in TTA-UC using MR-TADF molecules as photosensitizers have resulted in the development of green to ultraviolet, blue to ultraviolet, and even near-infrared to blue emission. This concept will summarize the research progress of MR-TADF molecules as photosensitizers in TTA-UC, analyzing the challenges and giving possible solutions. Finally, we prospect the future development of MR-TADF molecules as photosensitizers, including the molecular design as well as the possible application areas.
In Search of Visible Light Activatable Photocages: Structure‐Activity Relationship Study on C‐8 Substituted Indene‐fused‐coumarinyl Photoremovable Protecting Groups
A series of C-8 substituted indeno[1,2-g]coumarin-based photoremovable protecting groups (PPGs) were synthesized. para-Substituted benzoic acids were employed as leaving groups to evaluate their photolytic efficiency. Substitution of phenyl groups was proved to have negative impacts on photochemical properties of the PPGs, including but not limited to: retarded photolysis course, decreased uncaging quantum yield, and unsatisfactory cargo release yield. Electron-donating diethylamino substituted PPG 3d, a structural analogue of the widely used 7-diethylaminocoumarin PPG (DEACM), exhibited red-shifted absorption maximum and improved optical properties. Photochemical characterization revealed that PPG 3d not only showed comparable photolytic efficiency to DEACM at 365 nm and 405 nm, but also demonstrated superior sensitivity towards 465 nm wavelength, to which DEACM is unable to absorb and therefore, non-responsive. The >450 nm photosensitivity makes 3d a complement to DEACM for long wavelength excitation and a promising PPG for biological applications.