ABSTRACT
Vascular restenosis following angioplasty continues to pose a significant challenge. The heterocyclic trioxirane compound [1, 3, 5-tris((oxiran-2-yl)methyl)-1, 3, 5-triazinane-2, 4, 6-trione (TGIC)], known for its anticancer activity, was utilized as the parent ring to conjugate with a non-steroidal anti-inflammatory drug, resulting in the creation of the spliced conjugated compound BY1. We found that BY1 induced ferroptosis in VSMCs as well as in neointima hyperplasia. Furthermore, ferroptosis inducers amplified BY1-induced cell death, while inhibitors mitigated it, indicating the contribution of ferroptosis to BY1-induced cell death. Additionally, we established that ferritin heavy chain1 (FTH1) played a pivotal role in BY1-induced ferroptosis, as evidenced by the fact that FTH1 overexpression abrogated BY1-induced ferroptosis, while FTH1 knockdown exacerbated it. Further study found that BY1 induced ferroptosis by enhancing the NCOA4-FTH1 interaction and increasing the amount of intracellular ferrous. We compared the effectiveness of various administration routes for BY1, including BY1-coated balloons, hydrogel-based BY1 delivery, and nanoparticles targeting OPN loaded with BY1 (TOP@MPDA@BY1) for targeting proliferated VSMCs, for prevention and treatment of the restenosis. Our results indicated that TOP@MPDA@BY1 was the most effective among the three administration routes, positioning BY1 as a highly promising candidate for the development of drug-eluting stents or treatments for restenosis.
Subject(s)
Ferroptosis , Muscle, Smooth, Vascular , Nanoparticles , Ferroptosis/drug effects , Animals , Muscle, Smooth, Vascular/metabolism , Muscle, Smooth, Vascular/cytology , Humans , Nanoparticles/chemistry , Myocytes, Smooth Muscle/metabolism , Myocytes, Smooth Muscle/drug effects , Male , Mice , Mice, Inbred C57BL , Oxidoreductases/metabolism , FerritinsABSTRACT
Numerous electrochemistry reactions require the precise calculation of the ion solvation energy. Despite the significant progress in the first-principles calculations for crystals and defect formation energies for solids, the liquid system free energy calculations still face many challenges. Ion solvation free energies can be calculated via different semiempirical ways, e.g., using implicit solvent models or cluster of explicit molecule models; however, systematically improving these models is difficult due to their lack of a solid theoretical base. A theoretically sound approach for calculating the free energy is to use thermodynamic integration. Nevertheless, owing to the difficulties of self-consistent convergence in first-principles calculations for unphysical atomic configurations, the computational alchemy approach has not been widely used for first-principles calculations. This study proposes a general approach to use first-principles computational alchemy for calculating the ion solvation energy. This approach is also applicable for other small molecules. The calculated ion solvation free energies for Li+, Na+, K+, Be2+, Mg2+, and Ca2+ are close to the experimental results, and the standard deviation due to molecular dynamics fluctuations is within 0.06 eV.
ABSTRACT
Aqueous potassium-ion batteries (AKIBs) are considered promising electrochemical energy storage systems owing to their high safety and cost-effectiveness. However, the structural degradation resulting from the repeated accommodation of large K-ions and the dissolution of active electrode materials in highly dielectric aqueous electrolytes often lead to unsatisfactory electrochemical performance. This study introduces a high-entropy Prussian blue analog (HEPBA) cathode material for AKIBs, demonstrating significantly enhanced structural stability and reduced dissolution. The HEPBA exhibits a highly reversible specific capacity of 102.4 mAh g-1, with 84.4% capacity retention after undergoing 3448 cycles over a duration of 270 days. Mechanistic insights derived from comprehensive experimental investigations, supported by theoretical calculations, reveal that the HEPBA features a robust structure resistant to dissolution, a solid-solution reaction pathway with negligible volume variation during charge-discharge, and efficient ion transport kinetics characterized by a reduced band gap and a low energy barrier. This study represents a measurable step forward in the development of long-lasting electrode materials for aqueous AKIBs.
ABSTRACT
In two-dimensional magnets, the ultrafast photoexcited method represents a low-power and high-speed method of switching magnetic states. Bilayer CrI3 (BLC) is an ideal platform for studying ultrafast photoinduced magnetic phase transitions due to its stacking-dependent magnetic properties. Here, by using time-dependent density functional theory, we explore the photoexcitation phase transition in BLC from the R- to M-stacked phase. This process is found to be induced by electron-phonon interactions. The activated Ag and Bg phonon modes in the xy direction drive the horizontal relative displacements between the layers. The activated Ag mode in the z direction leads to a transition potential reduction. Furthermore, this phase transition can invert the sign of the interlayer spin interaction, indicating a photoinduced transition from ferromagnet to antiferromagnet. This investigation has profound implications for magnetic phase engineering strategies.
ABSTRACT
Magnesium metal batteries are promising candidates for next-generation high-energy-density and low-cost energy storage systems. Their application, however, is precluded by infinite relative volume changes and inevitable side reactions of Mg metal anodes. These issues become more pronounced at large areal capacities that are required for practical batteries. Herein, for the first time, double-transition-metal MXene films are developed to promote deeply rechargeable magnesium metal batteries using Mo2 Ti2 C3 as a representative example. The freestanding Mo2 Ti2 C3 films, which are prepared using a simple vacuum filtration method, possess good electronic conductivity, unique surface chemistry, and high mechanical modulus. These superior electro-chemo-mechanical merits of Mo2 Ti2 C3 films help to accelerate electrons/ions transfer, suppress electrolyte decomposition and dead Mg formation, as well as maintain electrode structural integrity during long-term and large-capacity operation. As a result, the as-developed Mo2 Ti2 C3 films exhibit reversible Mg plating/stripping with high Coulombic efficiency of 99.3% at a record-high capacity of 15 mAh cm-2 . This work not only sheds innovative insights into current collector design for deeply cyclable Mg metal anodes, but also paves the way for the application of double-transition-metal MXene materials in other alkali and alkaline earth metal batteries.
ABSTRACT
Great progress has been achieved in p-type SnS thermoelectric compound recently, while the stagnation of the n-type counterpart hinders the construction of thermoelectric devices. Herein, n-type sulfide PbSnS2 with isostructural to SnS is obtained through Pb alloying and achieves a maximum ZT of ~1.2 and an average ZT of ~0.75 within 300-773 K, which originates from enhanced power factor and intrinsically ultralow thermal conductivity. Combining the optimized carrier concentration by Cl doping and enlarged Seebeck coefficient through activating multiple conduction bands evolutions with temperature, favorable power factors are maintained. Besides, the electron doping stabilizes the phase of PbSnS2 and the complex-crystal-structure induced strong anharmonicity results in ultralow lattice thermal conductivity. Moreover, a maximum power generation efficiency of ~2.7% can be acquired in a single-leg device. Our study develops a n-type sulfide PbSnS2 with high performance, which is a potential candidate to match the excellent p-type SnS.
ABSTRACT
Weyl semimetals (WSMs) with high electrical conductivity and suitable carrier density near the Fermi level are enticing candidates for aqueous Zn-ion batteries (AZIBs), meriting from topological surface states (TSSs). We propose a WSM Co3 Sn2 S2 cathode for AZIBs showing a discharge plateau around 1.5â V. By introducing Sn vacancies, extra redox peaks from the Sn4+ /Sn2+ transition appear, which leads to more Zn2+ transfer channels and active sites promoting charge-storage kinetics and Zn2+ storage capability. Co3 Sn1.8 S2 achieves a specific energy of 305â Wh kg-1 (0.2 Ag-1 ) and a specific power of 4900â Wkg-1 (5 Ag-1 ). Co3 Sn1.8 S2 and Znx Co3 Sn1.8 S2 benefit from better conductivity at lower temperatures; the quasi-solid Co3 Sn1.8 S2 //Zn battery delivers 126â mAh g-1 (0.6 Ag-1 ) at -30 °C and a cycling stability over 3000â cycles (2 Ag-1 ) with 85 % capacity retention at -10 °C.
ABSTRACT
Single-atom metal catalysts (SACs) are used as sulfur cathode additives to promote battery performance, although the material selection and mechanism that govern the catalytic activity remain unclear. It is shown that d-p orbital hybridization between the single-atom metal and the sulfur species can be used as a descriptor for understanding the catalytic activity of SACs in Li-S batteries. Transition metals with a lower atomic number are found, like Ti, to have fewer filled anti-bonding states, which effectively bind lithium polysulfides (LiPSs) and catalyze their electrochemical reaction. A series of single-atom metal catalysts (Me = Mn, Cu, Cr, Ti) embedded in three-dimensional (3D) electrodes are prepared by a controllable nitrogen coordination approach. Among them, the single-atom Ti-embedded electrode has the lowest electrochemical barrier to LiPSs reduction/Li2 S oxidation and the highest catalytic activity, matching well with the theoretical calculations. By virtue of the highly active catalytic center of single-atom Ti on the conductive transport network, high sulfur utilization is achieved with a low catalyst loading (1 wt.%) and a high area-sulfur loading (8 mg cm-2 ). With good mechanical stability for bending, these 3D electrodes are suitable for fabricating bendable/foldable Li-S batteries for wearable electronics.
ABSTRACT
Potassium-ion batteries (KIBs) are promising electrochemical energy storage systems because of their low cost and high energy density. However, practical exploitation of KIBs is hampered by the lack of high-performance cathode materials. Here we report a potassium manganese hexacyanoferrate (K2Mn[Fe(CN)6]) material, with a negligible content of defects and water, for efficient high-voltage K-ion storage. When tested in combination with a K metal anode, the K2Mn[Fe(CN)6]-based electrode enables a cell specific energy of 609.7 Wh kg-1 and 80% capacity retention after 7800 cycles. Moreover, a K-ion full-cell consisting of graphite and K2Mn[Fe(CN)6] as anode and cathode active materials, respectively, demonstrates a specific energy of 331.5 Wh kg-1, remarkable rate capability, and negligible capacity decay for 300 cycles. The remarkable electrochemical energy storage performances of the K2Mn[Fe(CN)6] material are attributed to its stable frameworks that benefit from the defect-free structure.
ABSTRACT
Sodium-ion batteries (SIBs) based on conversion-type metal sulfide (MS) anodes have attracted extraordinary attention due to relatively high capacity and intrinsic safety. The highly reversible conversion of M/Na2 S to pristine MS in charge plays a vital role with regard to the electrochemical performance. Here, taking conventional MoS2 as an example, guided by theoretical simulations, a catalyst of iron single atoms on nitrogen-doped graphene (SAFe@NG) is selected and first used as a substrate to facilitate the reaction kinetics of MoS2 in the discharging process. In the following charging process, using a combination of spectroscopy and microscopy, it is demonstrated that the SAFe@NG catalyst enables an efficient reversible conversion reaction of Mo/Na2 SâNaMoS2 âMoS2 . Moreover, theoretical simulations reveal that the reversible conversion mechanism shows favorable formation energy barrier and reaction kinetics, in which SAFe@NG with the Fe-N4 coordination center facilitates the uniform dispersion of Na2 S/Mo and the decomposition of Na2 S and NaMoS2 . Therefore, efficient reversible conversion reaction MoS2 âNaMoS2 âMo/Na2 S is enabled by the SAFe@NG catalyst. This work contributes new avenues for designing conversion-type materials with an efficient reversible mechanism.
ABSTRACT
Herein, we report the synthesis and single crystal X-ray structure of Cu(II)-picolinic acid complex, 1 as a potent topoisomerase I inhibitor. The complex 1 crystallized in the triclinic crystal system with space group P-1. Comparative in vitro binding studies of complex 1 with CT DNA and tRNA were carried out revealing an electrostatic binding mode with higher binding propensity towards tRNA. The intrinsic bonding constant value, Kb was calculated to be 4.36 × 104 and 8.78 × 104 M-1 with CT DNA and tRNA respectively. DNA cleavage activity was carried out with a pBR322 plasmid DNA substrate to ascertain the cleaving ability. Furthermore, Topo-I inhibition assay of complex 1, performed via gel electrophoresis revealed a significant inhibitory effect on the enzyme catalytic activity at a minimum concentration of 15 µM. The DFT studies were carried out to provide better insight in the electronic transitions observed in the absorption spectrum of the complex 1. Molecular docking studies were carried out with DNA, RNA and Topo-I to determine the specific binding preferences at the target site and complement the spectroscopic studies. The antimicrobial potential of complex 1 was screened against E. coli, S. aureus, P. aeruginosa, B. subtilis and C. albicans; and compared with doxycycline, exhibiting an excellent maximum zone of inhibition of 28 mm against E. coli.Communicated by Ramaswamy H. Sarma.
Subject(s)
Anti-Infective Agents , Antineoplastic Agents , Copper , Escherichia coli , Molecular Docking Simulation , Staphylococcus aureus , Topoisomerase I Inhibitors/pharmacologyABSTRACT
Gold does not react with H2 to form bulk hydrides. Here we report the synthesis and characterization of a gold nanohydride protected by diphosphine ligands, [Au22 H4 (dppo)6 ]2+ [dppo=1,8-bis(diphenylphosphino)octane]. The Au22 core consists of two Au11 units bonded by eight Au atoms not coordinated by the diphosphine ligands. The four H atoms are found to bridge the eight uncoordinated Au atoms at the interface. Each Au11 unit can be viewed as a tetravalent superatom forming four delocalized Au-H-Au bonds, similar to the quadruple bond first discovered in the [Re2 Cl8 ]2- inorganic cluster. The [Au22 H4 (dppo)6 ]2+ nanohydride is found to lose H atoms over an extended time via H evolution (H2 ), proton (H+ ) and hydride (H- ) releases. This complete repertoire of H-related transformations suggests that the [Au22 H4 (dppo)6 ]2+ nanohydride is a versatile model catalyst for understanding the mechanisms of chemical reactions involving hydrogen on the surface of gold nanoparticles.
ABSTRACT
Constructing three-dimensional (3D) structural composite lithium metal anode by molten-infusion strategy is an effective strategy to address the severe problems of Li dendritic growth and huge volume changes. However, various challenges, including uncontrollable Li loading, dense inner structure, and low Li utilization, still need to be addressed for the practical application of 3D Li anode. Herein, we propose a self-propagating method, which is realized by a synergistic effect of chemical reaction and capillarity effect on porous scaffold surface, for fabricating a flexible 3D composite Li metal anode with high Li utilization ratio and controllable low Li loading. The composite 3D anode possesses controllable low loading (8.0-24.0 mAh cm-2) and uniform grid structure, realizing a stable cycling over 600 h at a high Li metal utilization ratio over 75%. The proposed strategy for fabricating composite 3D anode could promote the practical application of Li metal batteries.
ABSTRACT
Potassium ion batteries (PIBs) have shown great potential as a next-generation electrochemical energy storage system, due to the natural abundance of potassium and the relatively low redox potential of K ions. To accommodate the large ionic radius of K ions, conversion-type electrode materials are regarded as suitable candidates for K ion storage. However, the triggering mechanism of a conversion reaction in most anode materials of PIBs is unclear, which limits their further development. To reveal the mechanism, in this work, MoSe2, MoS2, and MoO2 were selected as model materials, guided by theoretical calculations, to investigate the K ion storage process. Through ex situ characterization, it was found that intercalation reactions preferentially occur in MoSe2 and MoS2, while an adsorption reaction preferentially occurs in MoO2. This is because of the larger interlayer spacing and lower K ion intercalation barrier in MoSe2 and MoS2 than in MoO2. The preferential intercalation reactions are able to induce a further conversion reaction by reducing the reaction barrier, thereby realizing high K ion storage capacities. As a result, the MoSe2-rGO and MoS2-rGO hybrids showed higher reversible capacities than the MoO2-rGO hybrid. By demonstrating a relationship between intercalation and the conversion reaction and understanding the mechanism, guidance is provided for selecting the electrode materials to obtain PIBs with high performance.
ABSTRACT
Electrochemical carbon dioxide reduction reaction (CO2 RR) represents a promising way to generate fuels and chemical feedstock sustainably. Recently, studies have shown that two-dimensional metal carbides and nitrides (MXenes) can be promising CO2 RR electrocatalysts due to the alternating -C and -H coordination with intermediates that decouples scaling relations seen on transition metal catalysts. However, further by tuning the electronic and surface structure of MXenes it should still be possible to reach higher turnover number and selectivities. To this end, defect engineering of MXenes for electrochemical CO2 RR has not been investigated to date. In this work, first-principles modelling simulations are employed to systematically investigate CO2 RR on M2 XO2 -type MXenes with transition metal and carbon/nitrogen vacancies. We found that the -C-coordinated intermediates take the form of fragments (e. g., *COOH, *CHO) whereas the -H-coordinated intermediates form a complete molecule (e. g., *HCOOH, *H2 CO). Interestingly, the fragment-type intermediates become more strongly bound when transition-metal vacancies are present on most MXenes, while the molecule-type intermediates are largely unaffected, allowing the CO2 RR overpotential to be tuned. The most promising defective MXene is Hf2 NO2 containing Hf vacancies, with a low overpotential of 0.45â V. More importantly, through electronic structure analysis it could be observed that the Fermi level of the MXene changes significantly in the presence of vacancies, indicating that the Fermi level shift can be used as an ideal descriptor to rapidly predict the catalytic performance of defective MXenes. Such an evaluation strategy is applicable to other catalysts beyond MXenes, which could enhance high throughput screening efforts for accelerated catalyst discovery.
ABSTRACT
Heterostructure engineering is one of the most promising modification strategies toward improving sluggish kinetics for the anode of sodium ion batteries (SIBs). Herein, we report a systemic investigation on the different types of heterostructure interfaces' effects of discharging products (Na2O, Na2S, Na2Se) on the rate performance. First-principle calculations reveal that the Na2S/Na2Se interface possesses the lowest diffusion energy barrier (0.39 eV) of Na among three kinds of interface structures (Na2O/Na2S, Na2O/Na2Se, and Na2S/Na2Se) due to its smallest recorded interface deformation, similar electronegativity, and lattice constant. The experimental evidence confirms that the metal sulfide/metal selenide (SnS/SnSe2) hierarchical anode exhibits outstanding rate performance, where the normalized capacity at 10 A g-1 compared to 0.1 A g-1 is 45.6%. The proposed design strategy in this work is helpful to design high rate performance anodes for advanced battery systems.
ABSTRACT
In this study, a series of new flavones (2-phenyl-chromone), 2-naphthyl chromone, 2-anthryl-chromone, or 2-biphenyl-chromone derivatives containing 6 or 7-substituted tertiary amine side chain were designed, synthesized, and evaluated in acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibition. The results indicated that the alteration of aromatic ring connecting to chromone scaffold brings about a significant impact on biological activity. Compared with flavones, the inhibitory activity of 2-naphthyl chromone, 2-anthryl-chromone derivatives against AChE significantly decreased, while that of 2-biphenyl chromone derivatives with 7-substituted tertiary amine side chain is better than relative flavones derivatives. For all new synthesized compounds, the position of tertiary amine side chain obviously influenced the activity of inhibiting AChE. The results above provide great worthy information for the further development of new AChE inhibitors. Among the newly synthesized compounds, compound 5a is potent in AChE inhibition (IC50 = 1.29 ± 0.10 µmol/L) with high selectivity for AChE over BChE (selectivity ratio: 27.96). An enzyme kinetic study of compound 5a suggests that it produces a mixed-type inhibitory effect against AChE.
ABSTRACT
Accelerated conversion by catalysis is a promising way to inhibit shuttling of soluble polysulfides in lithium-sulfur (Li-S) batteries, but most of the reported catalysts work only for one direction sulfur reaction (reduction or oxidation), which is still not a root solution since fast cycled use of sulfur species is not finally realized. A bidirectional catalyst design, oxide-sulfide heterostructure, is proposed to accelerate both reduction of soluble polysulfides and oxidation of insoluble discharge products (e.g., Li2 S), indicating a fundamental way for improving both the cycling stability and sulfur utilization. Typically, a TiO2 -Ni3 S2 heterostructure is prepared by in situ growing TiO2 nanoparticles on Ni3 S2 surface and the intimately bonded interfaces are the key for bidirectional catalysis. For reduction, TiO2 traps while Ni3 S2 catalytically converts polysulfides. For oxidation, TiO2 and Ni3 S2 both show catalytic activity for Li2 S dissolution, refreshing the catalyst surface. The produced sulfur cathode with TiO2 -Ni3 S2 delivers a low capacity decay of 0.038% per cycle for 900 cycles at 0.5C and specially, with a sulfur loading of 3.9 mg cm-2 , achieves a high capacity retention of 65% over 500 cycles at 0.3C. This work unlocks how a bidirectional catalyst works for boosting Li-S batteries approaching practical uses.
ABSTRACT
The electrochemical hydrogen evolution reaction (HER), as a promising route for hydrogen production, demands efficient and robust noble-metal-free catalysts. Doping foreign atoms into an efficient catalyst such as CoSe2 could further enhance its activity toward the HER. Herein, we developed a solvothermal ion exchange approach to doping S into CoSe2 nanosheets (NSs). We provide a combined experimental and theoretical investigation to establish the obtained S-doped CoSe2 (S-CoSe2) nanoporous NSs as highly efficient and Earth-abundant catalysts for the HER. The optimal S-CoSe2 catalyst delivers a catalytic current density of 10 mA·cm-2 for the HER at an overpotential of only 88 mV, demonstrating that S-CoSe2 is one of the most efficient CoSe- and CoS-based catalysts for the HER. We performed density functional theory (DFT) calculations to determine the stable structural configurations of S-CoSe2, and on the basis of which, we calculated the hydrogen adsorption Gibbs free energy (ΔGH) on CoSe2, CoS2, and the S-CoSe2 and the barrier energies of the rate-determining step of the HER on S-CoSe2. DFT calculations reveal that S-doping not only decreases the absolute value of ΔGH (move toward zero) but also significantly lowers the kinetic barrier energy of the rate-determining step of the HER on S-CoSe2, leading to a greatly improved HER performance.
ABSTRACT
Electrocatalytic CO2 reduction reaction (CO2RR) is an attractive way to produce renewable fuel and chemical feedstock, especially when coupled with efficient CO2 capture and clean energy sources. On the fundamental side, research on improving CO2RR activity still revolves around late transition metal-based catalysts, which are limited by unfavorable scaling relations despite intense investigation. Here, we report a combined experimental and theoretical investigation into electrocatalytic CO2RR on Ti- and Mo-based MXene catalysts. Formic acid is found as the main product on Ti2CTx and Mo2CTx MXenes, with peak Faradaic efficiency of over 56% on Ti2CTx and partial current density of up to -2.5 mA cm-2 on Mo2CTx. Furthermore, simulations reveal the critical role of the Tx group: a smaller overpotential is found to occur at lower amounts of -F termination. This work represents an important step toward experimental demonstration of MXenes for more complex electrocatalytic reactions in the future.