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Yolk–shell Pd@hollow@C-X (X = 1.5, 3.2, 4.5 and 6) catalysts with Pd as the core and porous carbon as the shell were prepared via the inverse microemulsion method. The carbon shell pore volume and core Pd size were controlled by varying the NH3·H2O amount. Results showed that with an increase in the NH3·H2O amount, the average particle size of Pd nanoparticles and shell pore volume decreased first and then increased, and when the NH3·H2O amount was 3.2 ml, the as-prepared Pd@hollow@C-3.2 catalyst had the smallest Pd particle size and largest shell pore volume as 5.54 ± 1.37 nm and 0.12 m3 g−1, respectively. The smaller Pd particle size can provide more active sites for the adsorption and reaction of H2 and O2 reactants, and the larger shell pore volume is beneficial for their adsorption. This makes the Pd@hollow@C-3.2 catalyst possess the highest selectivity and productivity in the H2O2 synthesis, reaching 93% and 3197 mmol (gPd−1 h−1)−1, respectively, at 1 bar. [ABSTRACT FROM AUTHOR]

Activatedcarbons (ACs) were modified separately by impregnationwith different types of metal ions, Al3+, Mg2+, Li+, Fe3+, and Ag+in this work.Adsorption breakthrough experiments of dichloromethane (DCM) werecarried out for measuring working adsorption capacities (Qm) of modified ACs toward DCM, and temperatureprogrammed desorption (TPD) experiments were conducted for estimatingdesorption activation energy (Ed) of DCMon these ACs. The effects of metal ions on the adsorption/desorptionof DCM on the modified ACs were discussed with the help of hard andsoft acid and base (HSAB) theory. Results showed that Qmof DCM on these ACs followed the order: QAl(III)/AC> QLi(I)/AC> QMg(II)/AC> QFe(III)/AC> QAC> QAg(I)/AC, and the Edof DCMfollowed the same order. As compared to that of the original AC, thesurface local acid hardness of the modified ACs was enhanced withthe doping of hard acid metal ions such as Al3+, Li+, Mg2+, and Fe3+, and thus the interactionsbetween DCM and Al(III)/AC, Li(I)/AC, Mg(II)/AC, and Fe(III)/AC surfaceswere also enhanced due to the hard base characteristic of DCM. However,when the AC was doped with soft acid Ag+, its surface localacid hardness was decreased. As a result, the interaction betweenDCM and Ag(I)/AC was weakened. [ABSTRACT FROM AUTHOR]

• A nest-shaped hollow-encapsulated Pd catalyst named Pd Multi @ONHCS, was successfully synthesized and used for the first time in DSHP at atmospheric pressure. • The special structure of Pd Multi @ONHCS catalyst creates a distinctive catalytic microreactor environment with a spatial mass transfer constraint for DSHP. • Experimental and molecular dynamics simulation both show that the hollow structure of Pd Multi @ONHCS catalyst significantly affects DSHP performance by influencing spatial mass transfer and diffusion resistance within the carbon nanopores. A well-defined structural morphology can significantly construct a special catalytic micro-reaction environment to enhance the catalytic performance of Pd catalyst in the direct synthesis of hydrogen peroxide from hydrogen and oxygen (DSHP). In this study, SiO 2 was used as a rigid template, PdCl 2 as the Pd precursor, and dopamine hydrochloride (DA) as the carbon and nitrogen source to synthesize a nest-shaped hollow-encapsulated Pd catalyst named Pd Multi @ONHCS. This catalyst was successfully constructed via high-temperature pyrolysis of poly dimethyl diallyl ammonium chloride (PDDA), which generated a blasting effect crucial for this formation. Characterization analysis, catalytic performance evaluation experiment, and molecular dynamics simulation were conducted to explore the structure-performance relationship of Pd Multi @ONHCS catalyst in DSHP. Both experimental and simulation results consistently showed that the nest-shaped hollow structure of Pd Multi @ONHCS catalyst created a distinctive catalytic microreactor environment with a spatial mass transfer constraint, which was not only conducive to adsorption and enrichment of H 2 and O 2 at Pd active sites to produce H 2 O 2. In addition, the generated H 2 O 2 can be desorbed from Pd active sites in time and rapidly diffused into the reaction solution, effectively inhibiting the dissociation of species containing O O bonds on the Pd surface, resulting in severe hydrogenation and decomposition side reactions, and improving H 2 O 2 productivity and selectivity. By organically combining carbon support with structural morphology, a nest-shaped hollow-encapsulated Pd catalyst named Pd Multi @ONHCS catalyst was successfully constructed and first used for DSHP from H 2 and O 2 at atmospheric pressure. Pd Multi @ONHCS catalyst with a new structural morphology provided a distinctive catalytic microreactor cavity and constraint effect of spatial mass transfer to enhance the catalytic performance for DSHP, ultimately improving H 2 O 2 productivity and H 2 O 2 selectivity. [Display omitted] [ABSTRACT FROM AUTHOR]

The direct synthesis of hydrogen peroxide (H2O2) was studied by using a series of catalysts Pd/CNT-X (X = N, O) prepared by ethylene glycol reduction, which allows for better control of Pd nanoparticle size and catalyst hydrophilicity. The doping of both N and O into a carbon carrier could anchor Pd nanoparticles and enhance the hydrophilicity of catalysts, which would lead to significantly enhanced H2O2 productivity and stability compared to the original catalyst Pd/CNT. Detailed characterization indicated that this improvement was due to selective tuning of the Pd nanoparticle size, Pd0/Pd2+ ratio and catalyst hydrophilicity. [ABSTRACT FROM AUTHOR]

• A high-performance Pd-Ni/NPCs catalyst for directly synthesizing hydrogen peroxide was easily prepared using a simple chemical displacement method. • Ni modification regulates the electronic structure of Pd through electron transfer and compressive stress, leading to electron enrichment in Pd and lowering the d -band center of Pd. • Ni modulates the electronic structure of Pd, reducing the hydrogenation activation energies of O 2 * and OOH* and increasing the dissociation activation energies of O 2 *, OOH*, and HOOH*, which improves the selectivity and productivity of H 2 O 2. • Crystal Orbital Hamilton Population (COHP) analysis shows a correlation between energy-integrated COHP (ICOHP) of O O bonds in reaction intermediates and activation energies, providing insights into the catalyst's surface reaction mechanism. • Synthesized Pd-Ni/NPCs catalysts based on theoretical predictions demonstrate excellent H 2 O 2 selectivity and productivity, validating the effectiveness of the proposed catalyst design strategy. Developing high-performance catalysts for direct synthesis of hydrogen peroxide (H 2 O 2 ; DSHP) remains challenging. The paper proposes a strategy to optimize Pd catalysts by enriching Ni-modified N-doped porous carbon. The theoretical studies indicate that Ni modulates the electronic structure of Pd through charge transfer and strain effects, effectively reducing the adsorption energy of reaction intermediates. Furthermore, the Crystal Orbital Hamilton Population (COHP) analysis demonstrated that the energy-integrated COHP (ICOHP) of the O O bonds in O 2 * (* denotes the adsorbed state), OOH*, and HOOH* were positively correlated with dissociation activation energies and negatively correlated with hydrogenation activation energies. The modulation of the electronic structure of Pd by Ni reduces the hydrogenation activation energies of O 2 * and OOH* and increases the dissociation activation energies of O 2 *, OOH*, and HOOH*, thereby enhancing the selectivity and productivity of H 2 O 2. The experimental results aligned with the theoretical predictions, showcasing that the optimized Pd-Ni 7.5 /NPCs catalyst exhibited remarkable H 2 O 2 selectivity and productivity of 70.5 % and 230.31 mol kg cat -1·h-1, respectively, surpassing the performance of Pd/NPCs (47.1 % and 52.3 mol kg cat -1·h-1). This study offers profound insights into the crucial role of electron effects in DSHP using nickel-modified palladium catalysts, providing strong evidence into the design and optimization of Pd catalysts. [Display omitted] [ABSTRACT FROM AUTHOR]

High-entropy oxides (HEOs) is a new type of catalyst that has emerged in recent years. High-entropy oxides, which is doped by a variety of metal cations and form a single-phase solid solution with a uniquely stabilized structure, is a strong contender for ideal catalysts due to their elemental versatility and designability. However, high-entropy oxides (HEOs) had not yet emerged in the field of gas-phase catalysis, here we reported the selection of five metal salts Zn(NO 3) 2 ·6H 2 O, Cu(NO 3) 2 ·3H 2 O, Co(NO 3) 2 ·6H 2 O, Ni(NO 3) 2 ·6H 2 O and Fe(NO 3) 3 ·9H 2 O, a high-entropy oxide FeNiCuZnCoO x was successfully prepared and uniformly loaded on activated carbon using wet chemistry, it was applied to the catalytic oxidation and removal of SO 2 in industrial flue gas, and the structural mechanism of HEOs affecting desulfurization capacity was described. The oxygen vacancy structure produced by the typical lattice distortion effect of high-entropy oxides greatly improved the catalytic activity of activated carbon, and the desulfurization capacity was significantly improved, in which the maximum saturated adsorption reached 40.93 mg/g at 293 K. [Display omitted] Catalytic oxidation mechanism of KAC-HEOs. • Successfully prepared HEOs loaded on activated carbon and applied them to the catalytic oxidation and removal of SO 2 in industry for the first time. • Explained the mechanism of catalytic oxidation and removal of SO 2 using the unique oxygen defect structure of HEOs. • Solved the problem of loading agglomeration by chemical treatment, so that the HEOs was uniformly dispersed and the desulfurization capacity was enhanced. [ABSTRACT FROM AUTHOR]

Yolk–shell Pd@hollow@C-X (X = 1.5, 3.2, 4.5 and 6) catalysts with Pd as the core and porous carbon as the shell were prepared via the inverse microemulsion method. The carbon shell pore volume and core Pd size were controlled by varying the NH3·H2O amount. Results showed that with an increase in the NH3·H2O amount, the average particle size of Pd nanoparticles and shell pore volume decreased first and then increased, and when the NH3·H2O amount was 3.2 ml, the as-prepared Pd@hollow@C-3.2 catalyst had the smallest Pd particle size and largest shell pore volume as 5.54 ± 1.37 nm and 0.12 m3 g−1, respectively. The smaller Pd particle size can provide more active sites for the adsorption and reaction of H2 and O2 reactants, and the larger shell pore volume is beneficial for their adsorption. This makes the Pd@hollow@C-3.2 catalyst possess the highest selectivity and productivity in the H2O2 synthesis, reaching 93% and 3197 mmol (gPd−1 h−1)−1, respectively, at 1 bar. [ABSTRACT FROM AUTHOR]

Pt 3 Co NPs anchored on B, N co-doped multiwalled carbon nanotubes demonstrate excellent catalytic activity and durability for MOR in acidic media. Both Pt alloying with Co and the co-doping of the MWCNTs acted synergistically to boost the catalytic activity and durability of Pt 3 Co/BN-MWCNTs. [Display omitted] • A Pt 3 Co/BN-MWCNTs catalyst was prepared containing Pt 3 Co NPs on B,N co-doped MWCNTs. • Pt 3 Co/BN-MWCNTs exhibited high activity, stability and CO tolerance during MOR. • The specific activity of Pt 3 Co/BN-MWCNTs for MOR was 6.35 times that of Pt/C. • The electronic structure of the Pt 3 Co NPs and B → C → N electron transfer aided MOR. • A strong metal-support interaction stabilized Pt 3 Co/BN-MWCNTs during MOR. Developing highly efficient and durable catalysts for the methanol oxidation reaction (MOR) is crucial to the commercialization and widespread uptake of direct methanol fuel cells (DMFCs). Carbon-supported Pt nanoparticle (NP) catalysts demonstrate high initial activities for MOR, but suffer from electrochemical instability. Herein, nanoalloying and heteroatom-doping strategies were adopted to prepare well-ordered intermetallic Pt 3 Co NPs anchored on B, N co-doped multiwalled carbon nanotubes, with the developed Pt 3 Co/BN-MWCNTs electrocatalyst offering high stability for MOR in 0.1 M HClO 4. Benefiting from the optimal electronic structure of the ordered Pt 3 Co NPs and asymmetric electron transfer (B → C → N) in the support, the activity, stability and CO poisoning resistance of Pt 3 Co/BN-MWCNTs electrocatalyst were significantly enhanced compared to a commercial Pt/C catalyst. Density functional theory (DFT) calculations revealed that electronegativity differences between Pt and Co enable significant charge redistribution, lowering the energy barriers and potentials for the oxidation of the *CO intermediate by OH* species, greatly enhancing MOR kinetics under acid conditions. Further, B, N co-doping of the MWCNTs strengthened the interaction with the Pt 3 Co NPs, further boosting MOR performance by suppressing Pt 3 Co dissolution into the electrolyte. The findings of this work are expected to be applied in catalyst design for a wide range of energy conversion devices. [ABSTRACT FROM AUTHOR]

Solid waste and heavy metal pollution are long-term and challenging subjects in the field of environmental engineering. In this study, we propose a sustainable approach to "treating waste with waste" by utilizing the ultramicropore biochar derived from solid waste distiller's grains as a means to remove Cr(VI) from simulated wastewater and wet phosphoric acid. The biochar prepared in this research exhibit extremely high specific surface areas (up to 2973 m2/g) and a well-developed pore structure, resulting in a maximum Cr(VI) adsorption capacity of 426.0 mg/g and over 99% removal efficiency of Cr(VI). Furthermore, the adsorbent can be reused for up to eight cycles without significant reduction in its Cr(VI) adsorption performance. Mechanistic investigations suggest that the exceptional Cr(VI) adsorption capacity can be attributed to the synergistic effect of electrostatic interaction and reduction adsorption. This study offers an alternative approach for the resource utilization of solid waste distiller's grains, and the prepared biochar holds promise for the removal of Cr(VI) from wastewater and wet-process phosphoric acid. [Display omitted] • Biochar derived from distiller's grains is used for removal Cr(VI). • Biochar exhibits a remarkably high specific surface area. • A maximum adsorption capacity for Cr(VI) of 426.0 mg/g is acquired. • A combined physical and chemical interaction for Cr(VI) removal is proposed. [ABSTRACT FROM AUTHOR]

[Display omitted] • One step rapid synthesis of porous carbon. • Phosphorus in PPA mainly exists in the form of orthophosphoric acid, while in RPPA it mainly exists in the form of polyphosphoric acid and polyphosphate. • Polyphosphoric acid and polyphosphates can promote the development of mesoporous volume. • AC-R has adsorption performance comparable to AC-N, with an adsorption capacity of 523.63 mg/g. • Solid waste recycling and utilization, green and environmentally friendly. Despite the widespread utilization of phosphoric acid (PPA) as an activator in the preparation of biomass-derived porous carbon materials, limited research has focused on utilizing recycled phosphoric acid (RPPA) for this purpose. Here, we revealed the in situ morphological transformation of phosphorus and its influence on the mechanism of porosity development in porous carbon materials. Furthermore, we examined the pore structure distribution, morphology, surface properties of the resulting carbon materials, as well as the influence of these properties on the adsorption behavior of tetracycline hydrochloride (TC). The abundant presence of a substantial quantity of polyphosphoric acid and polyphosphates in RPPA significantly contribute to the formation of a highly mesoporous structure in AC-R, achieving a mesopore volume of up to 0.65 cm3/g, which is larger than that of AC-N (0.23 cm3/g). This displays a molecular-level strategy that can adjust pore structure by regulating the type and content of polyphosphoric acid and polyphosphate during the one-step activation process, providing theoretical guidance for regulating pore structure of porous carbon materials. Moreover, AC-R exhibited effective TC uptake of 523.63 mg/g through pore adsorption, electrostatic interaction, metal ion complexation, hydrogen bonding, and π-π stacking interactions, showing comparable adsorption performance to AC-N (520.92 mg/g). [ABSTRACT FROM AUTHOR]

Herein, we have developed a new activation method to convert the hydrothermal carbon of cellulose by means of potassium citrate and urea into a carbon material with well-developed micropores and a high N content, which is capable of separating and enriching CH 4. [Display omitted] • C 6 H 5 K 3 O 7 was first used to prepare ultra-microporous carbon materials. • The mechanism of activated carbon prepared by C 6 H 5 K 3 O 7 and CH 4 N 2 O was proposed. • The micropore and nitrogen content are determined by the feed ratio. • Materials with higher micropores and N% have the maximum CH 4 adsorption capacity. • Study on the thermodynamics of methane adsorption. N-doped microporous carbons have attracted much attention for micromolecule gas separation and accumulation owning to their superior adsorption potential and surface polarizability. However, to prepare N-doped microporous carbon usually acquire excess corrosive KOH as activator, which limits its application in industry. Here, we propose a non-corrosion method for the manufacture of narrow N-doped microporous carbons using potassium citrate acts as activating agent, and urea acts as both a nitrogen doping agent and coactivator without any solvent. The BET surface area, micropore volume, pore size distribution and N content can be easily adjusted by changing the potassium citrate/urea ratio and activating temperature. The influence of porous structure and N content on CH 4 uptake and separation was investigated, and ultra-micropore volume (<1nm) plays a dominate role in CH 4 selectivity adsorption. ACK 2 N 1 had the largest CH 4 adsorption capacity of 3.00 mmol/g and CH 4 /N 2 selectivity of 7.11 at 273.15 K and 100 KPa due to its largest ultra-micropore volume and N content. The adsorption breakthrough, regeneration experiments and adsorption thermodynamics showed that the prepared well-developed N-doped microporous carbons have very good potential for CH 4 separation and enrichment from low coal bed methane. Furthermore, the pore formation mechanism of the well microporous carbon materials is proposed. [ABSTRACT FROM AUTHOR]

Binding hydrophobic ionic liquid [Bmim]PF 6 on the surface of Pd NPs not only increases the dissociation energy barrier of the O-O bonds of O 2 *, OOH*, and HOOH*, but also promotes the desorption of HOOH* from the active site, which effectively improves the selectivity and productivity of H 2 O 2. [Display omitted] • A nano-hybrid Pd catalyst was prepared for efficient direct synthesis of H 2 O 2. • Binding [Bmim]PF 6 on the surface of Pd NPs can increase the content of Pd2+. • The increase of Pd2+ content improves the dissociation energy barrier of O-O bond. • The hydrophobicity of [Bmim]PF 6 facilitates HOOH* desorption from Pd active site. • The steric hindrance of [Bmim]PF 6 improves the cyclic stability of the catalyst. Direct synthesis of hydrogen peroxide (H 2 O 2) from hydrogen (H 2) and oxygen (O 2) is an ideal industrial method to replace the anthraquinone oxidation process for H 2 O 2 production, however, it is still limited by low H 2 O 2 selectivity and productivity. The electronic structure and wettability of the catalyst are crucial factors that affects the catalytic performance. This study demonstrates that binding hydrophobic 1-butyl-3-methylimidazolium-hexafluorophosphate ([Bmim]PF 6) ionic liquid on the surface of Pd nanoparticles (Pd NPs) can increase the content of electron-deficient state Pd (Pd2+) at the active site, which exhibits excellent catalytic performance (90.8% H 2 O 2 selectivity and 8828.6 mmol g Pd −1h−1 H 2 O 2 productivity). The results of XPS, O 2 -TPD and DFT show that the increase of Pd2+ content effectively inhibits the O-O bond dissociation of O 2 *, OOH*, and HOOH*, thus improving H 2 O 2 selectivity and productivity. Moreover, the hydrophobicity of [Bmim]PF 6 induces a change in the three-dimensional hydrophilic microenvironment of the Pd active site, reducing the energy required for HOOH* desorption from the active site by 0.07 eV (from 0.53 eV to 0.46 eV). This is useful in preventing further hydrogenation and decomposition of HOOH*. TEM characterization suggests that the steric hindrance of [Bmim]PF 6 impedes the aggregation of Pd NPs during the reaction, resulting in different cyclic stability of Pd/OCNT and Pd [Bmim]PF 6 /OCNT. [ABSTRACT FROM AUTHOR]

Direct synthesis of hydrogen peroxide (DSHP) from oxygen (O 2 ) and hydrogen (H 2 ) offers a promising alternative to anthraquinone oxidation for hydrogen peroxide (H 2 O 2 ) production, yet challenges remain in achieving high selectivity and productivity. In this study, palladium octahedral nanoparticles (Pd ONPs) exposing Pd(111) facets were first synthesized, followed by the introduction of lead (Pb) atoms onto these facets to construct Pb-Pd(111) surface alloy structures (Pd@Pd-Pbx ONPs) for efficient DSHP. Characterization results indicated that the introduction of Pb atoms increased the electron density of Pd atoms and significantly reduced the number of low-coordinated Pd atoms. Density functional theory (DFT) calculations confirmed that the high electron density in Pd atoms downshifted their d-band center, thereby enhancing the adsorbed O 2 (O 2 *) and hydroperoxyl (OOH*) hydrogenation and promoting the adsorbed H 2 O 2 (HOOH*) desorption from Pd active sites, which was a key step in the formation of H 2 O 2 . Furthermore, the different coordination environments and electronic properties of Pd atoms that were close to Pb as opposed to those that were farther away produced a unique tilted adsorption configuration for O 2 *, OOH*, and HOOH* on the Pd-Pb(111) surface, effectively inhibiting OO bond dissociation. As a result, the TiO 2 -loaded Pd@Pd-Pb 4 ONPs (Pd@Pd-Pb 4 /TiO 2 ) catalyst achieved an H 2 O 2 selectivity of 80.6 % and a productivity of 6258.7 mmol g Pd -1 h -1 in the DSHP. This study underscores the impact of Pd catalyst surface modification on DSHP performance and provides valuable insights into the structure-performance relationship in bimetallic catalysts., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier Inc. All rights reserved.)

The global prevalence and incidence of non-alcoholic fatty liver disease (NAFLD) are exhibiting an increasing trend. NAFLD is characterized by a significant accumulation of lipids, though its underlying mechanism is still unknown. Here we report that high-fat diet (HFD) feeding induced hepatic steatosis in mice, which was accompanied by a reduction in the expression and function of hepatic TRPV2. Moreover, conditional knockout of TRPV2 in hepatocytes exacerbated HFD-induced hepatic steatosis. In an in vitro model of NAFLD, TRPV2 regulated lipid accumulation in HepG2 cells, and TRPV2 activation inhibited the expression of the cellular senescence markers p21 and p16, all of which were mediated by AMPK phosphorylation. Finally, we found that administration of probenecid, a TRPV2 agonist, impaired HFD-induced hepatic steatosis and suppressed HFD-induced elevation in p21 and p16. Collectively, our findings imply that hepatic TRPV2 protects against the accumulation of lipids by modulating p21 signalling., (© 2023. The Author(s) under exclusive licence to University of Navarra.)

A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was established for the simultaneous determination of 35 antibiotic residues of tetracyclines, sulfonamides, penicillins, macrolides and amphenicols in milk. The samples were extracted with alkaline acetonitrile and McIlvaine buffer solution under ultrasonication. The separation of target compounds was performed on an Eclipse XDB-C, column (150 mm x 2.1 mm, 3.5 µm) with gradient elution at a flow rate of 0.25 mL/min, and with an injection volume of 10 µL. The identification and quantification of the compounds were completed by liquid chromatography-tandem mass spectrometry in multiple reaction monitoring ( MRM) mode. The limits of detection were all below 10.0 µg/kg. The average spiked recoveries of the method ranged from 70. 1% to 109. 9% with relative standard deviations (RSDs) of 2.89%-9.99%. After validation, the method was applied to the analysis of antibiotic residues in milk products in China. Fifty samples were screened under the well defined methodology, and the results showed that chloramphenicol, only in one sample, was monitored with the content of 0.48 µg/kg. A risk of contamination of milk with chloramphenicol has been determined to exist. Therefore this method is convenient, rapid, sensitive and reliable, and can be successfully applied to the simultaneous detection of the 35 antibiotic residues of tetracyclines, sulfonamides, penicillins, macrolides and amphenicols in milk.