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Resveratrol (Res), which is a redox activation reagent, is a remarkably cheap and high-energy pseudocapacitive material because of possessing fast and reversible redox reactivity. Herein, we investigated Res as an organic compound with oxidation–reduction activity. One of the effective strategies to address these drawbacks, which are high costs, unfriendly environment, and short redox reactivity, is to composite Res with three-dimensional graphene structures. The obtained composites of Res/reduced graphene oxide (rGO) showed an abundance of active sites and a high specific capacitance. Res/rGO composites with different amounts of Res and GO were prepared using a one-step hydrothermal method. Electrochemical performance test results showed that the addition of Res resulted in a higher specific capacitance of the composite compared with that of rGO, reaching 588 F g–1 in 6 mol L–1 potassium hydroxide when the mass ratio of GO-to-Res was 3:1. In the specific capacitance at a current density of 2 A g–1, cycling stability was good, and the initial capacitance was 88.8% after 10,000 cycles. Adsorption energies and density of states of Res on graphene surfaces are calculated to further understand the charge storage mechanism by density functional theory. The calculation results show that Res plays a crucial role in excellent electrochemical performance. [ABSTRACT FROM AUTHOR]

As an atom-economical reaction, the direct generation of dimethyl carbonate (DMC) and ethylene glycol (EG) via the transesterification of CH 3 OH and ethylene carbonate (EC) has several promising applications, but the exploration of carriers with high specific surface areas and novel heterogeneous catalysts with more basic sites remains a long-standing research challenge. For this purpose, herein, a nitrogen-doped mesoporous carbon (NMC, 439 m 2 /g) based K-O 2 Lewis base catalyst (K-O 2 /NMC) with well-dispersed strongly basic sites (2.23 mmol/g, 84.5%) was designed and synthesized. The compositions and structures of NMC and K-O 2 /NMC were comprehensively investigated via Fourier transform infrared spectroscopy, X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, N 2 adsorption-desorption, CO 2 temperature-programmed desorption, and contact angle measurements. The optimal structural configuration and electron cloud distribution of the K-O 2 /NMC catalyst were simulated using first-principles calculations. The electron transfer predominantly manifested as a flow from K-O to C-O/C-N, and the interatomic interactions between each atom were enhanced and exhibited a tendency for a more stable state after redistribution. Furthermore, the adsorption energies ( E ads ) of CH 3 OH at K-O-O and K-O-N sites were -1.4185 eV and -1.3377 eV, respectively, and the O atom in CH 3 OH exhibited a stronger adsorption tendency for the K atom at the K-O-O site. Under the optimal conditions, the EC conversion, DMC/EG selectivity, and turnover number/frequency were 80.9%, 98.6%/99.4%, and 40.5/60.8 h -1 , respectively, with a reaction rate constant (k) of 0.1005 mol/(L·min). Results showed that the heterogeneous K-O 2 /NMC catalyst prepared herein greatly reduced the reaction cost while guaranteeing the catalytic effect, and the whole system required a lower reaction temperature (65 °C), a shorter reaction time (40 min), and a lower catalyst amount (2.0 wt % of EC). Therefore, K-O 2 /NMC can be used as a catalyst in different transesterification reactions.

Recent studies have identified butanone as a promising biomarker in the breath of lung cancer patients, yet the understanding of its gas-sensing properties remains limited. A key challenge has been to enhance the gas-sensing performance of materials toward butanone, particularly under ultraviolet light exposure. Herein, we report the synthesis of a novel three-dimensional composite material composed of SnO 2 incorporated with Bi 2 O 3 using facile hydrothermal and impregnation precipitation methods. Detailed physical and chemical characterizations were performed to assess the properties of the developed material. Upon activation with ultraviolet light, our composite exhibited exceptionally high sensitivity to butanone. Remarkably, the butanone response was nearly 3 times greater for the Bi 2 O 3 -loaded SnO 2 composite than for pristine SnO 2 , achieving a response value of 70. This substantial improvement is due to the synergistic effect of the material's distinctive three-dimensional architecture and the presence of Bi 2 O 3 , which significantly augmented the gas-sensing capability of butanone. To elucidate the underlying gas-sensing mechanism, we conducted first-principles calculations using density functional theory (DFT). The computational analysis revealed that the Bi 2 O 3 -containing system possesses superior adsorption energy for butanone. Ultimately, our findings suggest that the Bi-SnO 2 composite holds great promise as an optimal sensing material for the detection of butanone under ultraviolet illumination., Competing Interests: The authors declare no competing financial interest., (© 2024 The Authors. Published by American Chemical Society.)

To achieve a selective degradation of pollutants in a water body, 3D/1D magnetic molecularly imprinted fibers Fe 3 O 4 @TiO 2 /TC-TiO 2 /SiO 2 were fabricated by an electrospinning method. The molecularly imprinted layer was successfully prepared by a direct imprinting method using TiO 2 as a functional monomer. Fe 3 O 4 facilitates the catalyst recovery and light utilization. The as-prepared fibrous photocatalyst has a large specific surface area of 132.4 m 2 /g. The successful generation of imprinted sites was proven by various characterizations. The weak interaction between the inorganic functional monomer and tetracycline (TC) was determined to be van der Waals force and hydrogen bonds by the IGMH isosurface theory. The construction of the 3D/1D homojunction of molecularly imprinted materials is beneficial to charge transfer. The as-prepared photocatalyst exhibits a high selectivity coefficient α = 737.38 competing with RhB. The TC removal efficiency reached 100% within only 20 min. In addition, the possible degradation pathway and the degradation mechanism are reasonably proposed. This work not only provides an in-depth mechanism of the weak interaction between the inorganic molecularly imprinted functional monomer and pollutant molecules but also offers new thoughts on the fabrication of photocatalysts for the effective and selective treatment of pollutants in water bodies.

Coronaviruses have consistently posed a major global concern in the field of livestock industry and public health. However, there is currently a lack of efficient drugs with broad-spectrum antiviral activity to address the challenges presented by emerging mutated strains or drug resistance. Additionally, the method for identifying multitarget drugs is also insufficient. Aminopeptidase N (APN) and 3C-like proteinase (3CLpro) represent promising targets for host-directed and virus-directed strategies, respectively, in the development of effective drugs against various coronaviruses. In this study, maduramycin ammonium demonstrated a broad-spectrum antiviral effect by targeting both of the proteins. The binding domains 4 Å from the ligand of both target proteins shared a structural similarity, suggesting that screening and designing drugs based on these domains might exhibit broad-spectrum and highly effective antiviral activity. Furthermore, it was identified that the polyether ionophores' ability to carry zinc ion might be one of the reasons why they were able to target APN and exhibit antiviral effect. The findings of this experiment provide novel perspectives for future drug screening and design, while also offering valuable references for the utilization of polyether ionophores in the management of livestock health.

Direct regeneration has gained much attention in LiFePO 4 battery recycling due to its simplicity, ecofriendliness, and cost savings. However, the excess carbon residues from binder decomposition, conductive carbon, and coated carbon in spent LiFePO 4 impair electrochemical performance of direct regenerated LiFePO 4 . Herein, we report a preoxidation and prilling collaborative doping strategy to restore spent LiFePO 4 by direct regeneration. The excess carbon is effectively removed by preoxidation. At the same time, prilling not only reduces the size of the primary particles and shortens the diffusion distance of Li + but also improves the tap density of the regenerated materials. Besides, the Li + transmission of the regenerated LiFePO 4 is further improved by Ti 4+ doping. Compared with commercial LiFePO 4 , it has excellent low-temperature performance. The collaborative strategy provides a new insight into regenerating high-performance spent LiFePO 4 .

A photocatalytic annulation cascade of unactivated N -alkene-linked indoles with Langlois' reagent by a radical relay is developed at room temperature under blue LED irradiation. The reaction afforded a series of tri/difluoromethylated pyrrolo[1,2- a ]indoles in moderate to good yields. The DFT study suggests that the reaction is ascribed to a rhodamine 6G-induced cyclization cascade involving vinyl addition-radical relay and hydrogen-atom-abstraction (HAA) processes, and interestingly, pyrrolo[1,2- a ]indoles are applied as fluorescent dyes into the fluorescence spectrum and live-cell imaging. This paper represents an initial example on photocatalytic cyclization cascades by radical relay and the HAA process.

The rational design and construction of composite electrodes are crucial for overcoming the issues of poor working stability and slow ionic electron mobility of a single component. Nevertheless, it is a big challenge to construct core-shell heterostructures with crystalline/amorphous/crystalline heterointerfaces in straightforward and efficient methods. Here, we have successfully converted a portion of crystalline CoGa 2 O 4 into the amorphous phase by employing a facile sulfidation process (denoted as CoGa 2 O 4 -S), followed by anchoring crystalline NiCo-layered double hydroxide (denoted as NiCo-LDH) nanoarrays onto hexagonal plates and nucleation points of CoGa 2 O 4 -S, synthesizing dual-type hexagonal and flower-like 3D CoGa 2 O 4 -S@NiCo-LDH core-shell heterostructures with crystalline/amorphous/crystalline heterointerfaces on carbon cloth. Furthermore, we further adjust the Ni/Co ratio in LDH, achieving precise and controllable core-shell heterostructures. Benefiting from the abundant crystalline/amorphous/crystalline heterointerfaces and synergistic effect among various components, the CoGa 2 O 4 -S@Ni 2 Co 1 -LDH electrode exhibits a specific capacity of 247.8 mAh·g -1 at 1 A·g -1 and good rate performance. A CoGa 2 O 4 -S@Ni 2 Co 1 -LDH//AC flexible asymmetric supercapacitor provides an energy density of 58.2 Wh·kg -1 at a power density of 850 W·kg -1 and exhibits an impressive capacitance retention of 105.7% after 10,000 cycles at 10 A·g -1 . Our research provides profound insights into the design of other similar core-shell heterostructures.

Electrocatalytic hydrogen evolution reaction (HER) is receiving increasing attention as an effective process to produce clean energy. The commonly used precious metal catalysts can be hybridized with semiconductors to form heterostructures for the improvement of catalytic efficiency and reduction of cost. It will be promising to further improve the efficiency of heterostructure-based nanocatalysts in electrocatalytic and photocatalytic HER using a simple and effective method. Herein, we improve the efficiency of Au/TiO 2 in electrocatalytic and photo-electrocatalytic HER by selectively adsorbing p -aminothiophenol (PATP) molecules. The PATP molecules are adsorbed on the gold surface by using a simple solution-based method and favor the charge separation at the Au-TiO 2 interface. We also compare the PATP molecules with other thiophenol molecules in the enhancement of electrocatalytic HER. The PATP-induced enhancement in electrocatalysis is then further investigated by density functional theory (DFT) calculations, and this enhancement is attributed to a reduction in Gibbs energy of adsorbed hydrogen after surface adsorption of PATP molecules. This work provides a simple, cost-effective, and highly efficient approach to improve the electrocatalytic and photo-electrocatalytic efficiency of Au/TiO 2 , and this approach could be easily extended to other heterostructure-based nanocatalysts for performance enhancement and may be used in many other catalytic reactions.

A series of Cp*Ir (Cp* = pentamethylcyclopentadienyl) complexes with amidated 8-aminoquinoline ligands were synthesized and tested for formic acid (FA) dehydrogenation. These complexes showed improved activities compared to pristine 8-anminquinoline ( L1 ). Specially, amidation changed the outer coordination sphere of the complex ( 3 ) bearing N -8-quinolinylformamide ( L3 ), and 3 was proved to be a proton-responsive catalyst. Our experimental results and DFT calculations demonstrated that the deprotonated carbanion in L3 could interact with a water molecule to stabilize the transition states and lower the reaction energy barrier, which improved the reaction activity. A turnover frequency of 206250 h -1 was achieved by 3 under optimized conditions. This study presents a method to develop new ligands and modify the existing ligands for efficient FA dehydrogenation.

Iron sulfides are widely explored as anodes of sodium-ion batteries (SIBs) owing to high theoretical capacities and low cost, but their practical application is still impeded by poor rate capability and fast capacity decay. Herein, for the first time, we construct highly dispersed Fe 7 S 8 nanoparticles anchored on a porous N-doped carbon nanosheet (CN) skeleton (denoted as Fe 7 S 8 /NC) with high conductivity and numerous active sites via facile ion adsorption and thermal evaporation combined procedures coupled with a gas sulfurization treatment. Nanoscale design coupled with a conductive carbon skeleton can simultaneously mitigate the above obstacles to obtain enhanced structural stability and faster electrode reaction kinetics. With the aid of density functional theory (DFT) calculations, the synergistic interaction between CNs and Fe 7 S 8 can not only ensure enhanced Na + adsorption ability but also promote the charge transfer kinetics of the Fe 7 S 8 /NC electrode. Accordingly, the designed Fe 7 S 8 /NC electrode exhibits remarkable electrochemical performance with superior high-rate capability (451.4 mAh g -1 at 6 A g -1 ) and excellent long-term cycling stability (508.5 mAh g -1 over 1000 cycles at 4 A g -1 ) due to effectively alleviated volumetric variation, accelerated charge transfer kinetics, and strengthened structural integrity. Our work provides a feasible and effective design strategy toward the low-cost and scalable production of high-performance metal sulfide anode materials for SIBs.