Catalytic Active Sites Research Articles

Stability effects of alumina fibers on SnO2/Al2O3 NFs for efficient electrocatalytic performance towards CO2 reduction reaction

The weak stability of electrocatalysts seriously hinders the practical application in the field of electrocatalytic CO2 reduction reaction (CO2RR), so how to select catalyst supports and realize the ingenious combination between active sites and supports is still a challenge. In this work, alumina fibers (Al2O3 NFs) were employed to support Sn catalytic active sites with the aid of sol-gel methods and electrospinning. As-obtained SnO2-loaded aluminum oxide nanofibers (SnO2/Al2O3 NFs) catalyst possesses bulk-like SnO2 and nano-SnO2 loaded Al2O3 NFs. Interestingly, nano-SnO2 loaded Al2O3 NFs mainly contributes to the superior electrocatalytic properties towards CO2RR, particularly, faraday efficiency of formic acid (FEHCOOH) can reach 72.8% when the potential is -1.264 V, with HCOOH partial current density of 32.76 mA cm-2, and a long-term catalytic stability can be achieved. This study not only provides a new idea for enhancing the stability of electrocatalysts, but also expands the application field of Al2O3 NFs.

NiCo alloy-decorated nitrogen-doped carbon double-shelled hollow polyhedrons with abundant catalytic active sites to accelerate lithium polysulfides conversion

Lithium-sulfur (Li-S) batteries have received significant attention due to their high theoretical energy density. However, the inherent poor conductivity of S and lithium sulfide (Li2S), coupled with the detrimental shuttle effect induced by lithium polysulfides (LiPSs), impedes their commercialization. In this study, we develop NiCo alloy-decorated nitrogen-doped carbon double-shelled hollow polyhedrons (NC/NiCo DSHPs) as highly efficient catalysts for Li-S batteries. The distribution of NiCo alloy on both the inner and outer shells provides abundant catalytic active sites, effectively adsorbing LiPSs, mitigating the shuttle effect, and promoting the conversion between LiPSs and Li2S, even at high sulfur loadings. This results in enhanced redox kinetics within the Li-S system. Moreover, the highly conductive carbon material framework, enriched with carbon nanotubes and graphitic carbon layers, can greatly promote the efficient electron transportation. Additionally, the improved ion diffusion rates benefiting from the hollow structure can also be realized. By harnessing these synergistic effects, Li-S batteries incorporating the double-shelled NC/NiCo DSHP catalysts achieved a high specific capacity of 1310 mAh/g at 0.2C and a superior rate performance of 621 mAh/g at 4C. Furthermore, excellent cycling performance with ultralow capacity fading rate of only 0.045 % per cycle after 800 cycles at 1C was achieved. When sulfur loading reaches 6 mg cm−2, a high capacity of 4.6 mAh cm−2 at 0.1C after 100 cycles further validates the practical potential of this design. This study presents an innovative approach to alloy catalyst design, offering valuable insights for future research of Li-S batteries.

Enhanced Visible‐Light‐Driven Photocatalytic Overall Splitting of Pure Water in a Porous Microreactor

AbstractPhotocatalytic overall splitting of pure water (H2O) without sacrificial reagent to hydrogen (H2) and oxygen (O2) holds a great potential for achieving carbon neutrality. Herein, by anchoring cobalt sulfide (Co9S8) as cocatalyst and cadmium sulfide (CdS) as light absorber to channel wall of a porous polymer microreactor (PP12), continuous violent H2 and O2 bubbling productions from photocatalytic overall splitting of pure H2O without sacrificial reagent is achieved, with H2 and O2 production rates as high as 4.41 and 2.20 mmol h−1 gcat.−1 respectively. These are significantly enhanced than those in the widely used stirred tank‐type reactor in which no O2 is produced and H2 production rate is only 0.004 mmol h−1 gcat.−1. Besides improved charge separation and interaction of H2O with photocatalyst in PP12, bonding interaction of Co9S8 with PP12 creates abundant catalytic active sites for simultaneous productions of H2 and O2, thus leading to the significantly enhanced H2 and O2 bubbling productions in PP12. This offers a new strategy to enhance photocatalytic overall splitting of pure H2O without sacrificial reagent.

Tuning the peroxidase-mimic activity of CuX-trithiocyanuric acid complexes for colorimetric detection of gastric cancer-associated D-amino acids

A cascade colorimetric detection of salivary D-amino acids (DAAs) holds promise for the preliminary screening diagnosis of gastric cancer. Pursuing metal-organic complexes with high peroxidase-mimic (POD-mimic) activity is crucial to enhance diagnosis efficiency. In this work, we developed a straightforward strategy in a “one-pot” process to modulate the POD-mimic activity of CuX-trithiocyanuric acid (CuX-TTCA) complexes. By adjusting the molar ratios of CuX (Cl, Br, and I) and TTCA during synthesis to modify the coordination configuration of Cu(I) in CuX-TTCA, we easily tuned their POD-mimic activities. Among them, CuCl-TTCA-2 with a feeding molar ratio of 2:1 for CuCl:TTCA exhibited remarkable POD-mimic activity attributed to its exposed catalytic active sites and efficient mass transfer ability during catalysis. Long-lived 1O2 was identified as the primary reactive oxygen intermediate. A highly sensitive and selective cascade colorimetric detection platform was developed for two typical DAAs associated with gastric cancer, namely D-proline and D-alanine, achieving limit of detection values of 1.1 and 0.8 μM, respectively. As a proof-of-concept application, our cascade detection platform demonstrated excellent specificity in distinguishing saliva samples between gastric cancer patients and healthy individuals. The outstanding selectivity and reliable outcomes from DAAs assay make our detection platform highly promising for preliminary screening diagnosis of gastric cancer and patient self-detection applications. Our straightforward strategy for tuning POD-mimic activity provides an in-depth understanding on structure-activity relationship in nanozymes, offering valuable opportunities to advance enzyme-mimic optimization for other potential applications.

Enhanced Visible-Light-Driven Photocatalytic Overall Splitting of Pure Water in a Porous Microreactor.

Photocatalytic overall splitting of pure water (H2O) without sacrificial reagent to hydrogen (H2) and oxygen (O2) holds a great potential for achieving carbon neutrality. Herein, by anchoring cobalt sulfide (Co9S8) as cocatalyst and cadmium sulfide (CdS) as light absorber to channel wall of a porous polymer microreactor (PP12), continuous violent H2 and O2 bubbling productions from photocatalytic overall splitting of pure H2O without sacrificial reagent is achieved, with H2 and O2 production rates as high as 4.41 and 2.20 mmol h-1 gcat. -1 respectively. These are significantly enhanced than those in the widely used stirred tank-type reactor in which no O2 is produced and H2 production rate is only 0.004 mmol h-1 gcat. -1. Besides improved charge separation and interaction of H2O with photocatalyst in PP12, bonding interaction of Co9S8 with PP12 creates abundant catalytic active sites for simultaneous productions of H2 and O2, thus leading to the significantly enhanced H2 and O2 bubbling productions in PP12. This offers a new strategy to enhance photocatalytic overall splitting of pure H2O without sacrificial reagent.

Full‐Spectrum Light‐Harvesting Solar Thermal Electrocatalyst Boosts Oxygen Evolution

AbstractEnabling high‐efficiency solar thermal conversion (STC) at catalytic active site is critical but challenging for harnessing solar energy to boost catalytic reactions. Herein, we report the direct integration of full‐spectrum STC and high electrocatalytic oxygen evolution activity by fabricating a hierarchical nanocage architecture composed of graphene‐encapsulated CoNi nanoparticle. This catalyst exhibits a near‐complete 98 % absorptivity of solar spectrum and a high STC efficiency of 97 %, which is superior than previous solar thermal catalytic materials. It delivers a remarkable potential decrease of over 240 mV at various current densities for electrocatalytic oxygen evolution under solar illumination, which is practically unachievable via traditionally heating the system. The high‐efficiency STC is enabled by a synergy between the regulated electronic structure of graphene via CoNi‐carbon interaction and the multiple absorption of lights by the light‐trapping nanocage. Theoretical calculations suggest that high temperature‐induced vibrational free energy gain promotes the potential‐limiting *O to *OOH step, which decreases the overpotential for oxygen evolution.

Tailoring rGO[sbnd]Cu-Cu2O as a three-dimensional catalytic system in boosting of methanol electro-oxidation reaction

Tailoring a reduced graphene oxide-Cu-Cu2O (rGOCu-Cu2O) as a three-dimensional (3D) integrated catalytic system via an in-situ potential-controlled electrodeposition approach is a feasible pathway to boost methanol oxidation reaction (MOR) for direct methanol fuel cell. The enhancement in catalytic functionality and performances is due to the synergistic interaction between the in-situ electroreduced graphene oxide (rGO) and copper metal ions over it. The sequential and synergistic effect of the co-deposition potential, optimized time, and probable corrosion-promotion effect (formation of a galvanic cell between rGO and copper due to entrapped dissolved oxygen) is believed to be responsible for the structural growth of as-developed 3D catalytic systems. The MOR results suggest that the composite material deposited at the higher cathodic deposition potential (-1.2 V vs SCE), i.e., rGOCu (c) featured the remarkable lowest onset oxidation potential (i.e., +0.37 V), peak potential (i.e., +0.73 V), peak current density (135.76 mAcm−2), potentiostatic durability at +0.6 V after 3.5 h (∼65.85 mAcm−2) and outstanding cyclic stability (∼97.7 % current retention after 500 cycles), which is superior to the other modified composite electrodes. The enhanced performances are due to the effective dissociative adsorption of methanol from the available active catalytic site's and the presence of hydroxyl groups which has probably improved the oxidation of adsorbed intermediates from the surface. Further, Fourier-transform infrared (FT-IR) experiments revealed that formate as an active intermediate is being generated on all three rGOCu-Cu2O modified electrodes and follows the non-CO reaction pathway for direct oxidation of methanol.

High-entropy alloy-enhanced ZnCdS nanostructure photocatalysts for hydrogen production

High-entropy alloys (HEA) have been shown to be potential cocatalysts for photocatalysis, but the design of ideal semiconductor/HEA composite photocatalysts is challenging due to the complexity of their composition and the interactions within multi-element systems. To address this issue, PtCuFeNiCo HEA was selected as a cocatalyst, and a ZnCdS/PtCuFeNiCo (abbreviated as ZnCdS/HEA) nanostructured photocatalyst was designed for hydrogen production from water splitting. ZnCdS/HEA was prepared using a simple liquid-phase precipitation method, a template-assisted cation exchange method, and an ultrasound-assisted recombination method. Photocatalytic experiments showed that the hydrogen production activity of ZnCdS/HEA under visible light was 5.99 mmol·g−1·h−1, which is 11.7 times that of ZnCdS and significantly higher than that of ZnCdS/Pt. Experiments and density functional theory calculations indicated that ZnCdS/HEA formed a Schottky heterojunction. The performance enhancement was attributed to the synergistic effect between PtCuFeNiCo HEA and ZnCdS, which enhanced light absorption, improved the separation and transfer of photogenerated electrons and holes, as well as provided abundant catalytic active sites and increased surface reaction activity. This study highlights the potential of HEAs and provides theoretical and experimental references for the rational design of efficient semiconductor/HEA composite materials.

Comparative Study of Si−O−Al and Si−O−Si Bond Stability in HZSM‐5 Zeolite Under Steam and Hot Liquid Water Environments

AbstractUnderstanding the changes in the zeolite framework and catalytic active sites during zeolite‐based vapor‐phase and aqueous catalytic processes is crucial. Herein, the evolution of framework T atoms (Si and Al) in ammonium hexafluorosilicate (AHFS)‐treated HZSM‐5 zeolite under steam and hot liquid water (HLW) environments was inverstigated using various characterization techniques. In HLW, Si−O−Si bonds exhibit poorer hydrothermal stability than Si−O−Al bonds, in contrast to steam. Significant Si atom leaching occurs regardless of whether the framework tetrahedral Al atoms (Al(IV)‐1) are removed. Similar to steam, Al(IV)‐1 species in HLW sequentially evolve into partially coordinated framework Al species and then into extra‐framework Al (EFAL) species through partial and complete hydrolysis. The generated EFAL species act as Lewis acid sites, but their local structures or chemical environments may differ. These findings reveal the difference in the T−O−T bonds attacked by water molecules: the Si−O−Al bonds are primarily attacked in steam, whereas the Si−O−Si bond are primarily attacked in HLW.

Electronic synergy between NiCo2O4 and adjacent carbon defects to enhance styrene cracking activity for styrene-saturated activated carbon regeneration

The design and construction of catalysts featuring abundant electron transfer and defect structures for the regeneration of styrene-saturated activated carbon (AC) pose a significant challenge. This paper presents successful preparation of a regenerated adsorbent with synergistic catalytic active sites of NiCo2O4 spinel and carbon defects using a simple impregnation method. Enhanced catalytic activity is attributed to the electronic synergy between NiCo2O4 and carbon defects in 2.5Ni-2.5Co-900, involving substantial electron transfers, abundant acidic sites, and strong reducibility. Reactive oxygen species and the robust oxygen transfer facilitate the deep oxidation of intermediates and carbon elimination. The optimized regenerated adsorbent achieved a styrene adsorption capacity of 446.4 mg/g with a recovery of 92.4 % of the fresh sample, which is 1.5 times higher than 5Ni-900 and about 1.8 times higher than the unmodified regenerated activated carbon sample, RAC-900. The mechanism of styrene cracking and the evolution of intermediates were investigated using thermogravimetric-infrared coupling, and the effects of catalytic temperature and active sites on styrene cracking, deep oxidation of intermediates, and elimination of carbon deposits were explored. Kinetic analysis demonstrated that the adsorption of styrene on regenerated samples entailed a multifaceted process integrating both physical and chemical adsorption. The significance of chemical adsorption became increasingly evident as the concentration of defective sites grew. Intra-pore diffusion is the main determining step of the adsorption process. After five cycles, the adsorption capacity of 2.5Ni-2.5Co-900 decreased to below 25 %, suggesting promising strategies to overcome challenges of regenerating styrene-saturated AC.

Mesoporous carbon nanospheres doped with rich non-metallic and metallic catalytic active sites: A high-performance electrochemical platform for sensing of chloramphenicol in food samples

The development of a low-cost, accurate sensing strategy for trace levels of chloramphenicol (CAP) residues in food is crucial but remains challenging. In this study, a high-performance electrochemical platform was developed to detect CAP in animal-derived foods using Ni2P embedded N, P-co-doped mesoporous carbon nanospheres (Ni2P@N,P-MCS). The Ni2P@N,P-MCS material, with a unique mesoporous structure and large specific surface area, exhibited excellent adsorption properties. The N, P-co-doped heteroatoms enhanced the electric conductivity and active centers of MCS, facilitating fast mass transport and electron transfer. The introduction of Ni2P increased the active sites and enhanced the electrocatalytic activity. Leveraging these advantages, the electrochemical sensor based on Ni2P@N,P-MCS demonstrated outstanding detection performance with a wide linear range from 0.04 to 250 μM and a low limit of detection of 12 nM. The sensor also showed good reproducibility, stability, and anti-interference properties. Furthermore, the sensor was successfully tested in milk and pork samples, showing satisfactory recovery rates and indicating its feasibility for real sample analysis.

Selective catalytic activation of peroxymonocarbonate over a Co/Al2O3 catalyst

We assessed the selective catalytic performance of Co/Al2O3 in activating HCO4- for tetracycline degradation by studying the activation of oxidants and the generation of reactive oxygen species. Co/Al2O3 exhibited high catalytic selectivity towards HCO4- in the presence of H2O2, achieving a H2O2 utilization efficiency of 74.9 % for the production of ·OH. The Co/Al2O3-catalyzed HCO4--based system oxidized 89.2 % of tetracycline primarily through ·OH and CO3·− generated from HCO4- activation, while ·O2− and 1O2 played minor roles in degradation. Low-valent cobalt species served as catalytic active sites for HCO4- activation. Abundant oxygen vacancies on Co/Al2O3 accelerated the electron transfer, forming a local electron-rich region that preferentially adsorbed electrophilic HCO4- and provided additional active sites for HCO4- activation. Furthermore, the increased Lewis acid sites assisted HCO4- activation by stabilizing the leaving carbonate groups. This work offers insights into the structure-activity relations of catalysts for the selective catalytic activation of HCO4-.

Unveiling the potential role of virus-encoded polyphosphate kinases in enhancing phosphorus removal in activated sludge systems

While microbial phosphate removal in activated sludge (AS) systems has been extensively studied, the role of viruses in this process remains largely unexplored. In this study, we identified 149 viral auxiliary metabolic genes associated with phosphorus cycling from 2,510 viral contigs (VCs) derived from AS systems. Notably, polyphosphate kinase 1 (ppk1) and polyphosphate kinase 2 (ppk2) genes, which are primarily responsible for phosphate removal, were found in five unclassified VCs. These genes exhibited conserved protein structures and active catalytic sites, indicating a pivotal role of viruses in enhancing phosphorus removal. Phylogenetic analysis demonstrated a close relationship between viral ppk genes and their bacterial counterparts, suggesting the occurrence of horizontal gene transfer. Furthermore, experimental assays validated that viral ppk genes enhanced host phosphate removal capabilities. VCs carrying ppk genes were observed across diverse ecological and geographical contexts, suggesting their potential to bolster host functions in varied environmental and nutrient settings, spanning natural and engineered systems. These findings uncover a previously underappreciated mechanism by which viruses enhance phosphate removal in wastewater treatment plants. Overall, our study highlights the potential for leveraging virus-encoded genes to improve the efficiency of biological phosphorus removal processes, offering new insights into the microbial ecology of AS systems and the role of viruses in biogeochemical cycling.

Multi‐Enzyme Mimetic MoCu Dual‐Atom Nanozyme Triggering Oxidative Stress Cascade Amplification for High‐Efficiency Synergistic Cancer Therapy

AbstractSingle‐atom nanozymes (SAzymes) with ultrahigh atom utilization efficiency have been extensively applied in reactive oxygen species (ROS)‐mediated cancer therapy. However, the high energy barriers of reaction intermediates on single‐atom sites and the overexpressed antioxidants in the tumor microenvironment restrict the amplification of tumor oxidative stress, resulting in unsatisfactory therapeutic efficacy. Herein, we report a multi‐enzyme mimetic MoCu dual‐atom nanozyme (MoCu DAzyme) with various catalytic active sites, which exhibits peroxidase, oxidase, glutathione (GSH) oxidase, and nicotinamide adenine dinucleotide phosphate (NADPH) oxidase mimicking activities. Compared with Mo SAzyme, the introduction of Cu atoms, formation of dual‐atom sites, and synergetic catalytic effects among various active sites enhance substrate adsorption and reduce the energy barrier, thereby endowing MoCu DAzyme with stronger catalytic activities. Benefiting from the above enzyme‐like activities, MoCu DAzyme can not only generate multiple ROS, but also deplete GSH and block its regeneration to trigger the cascade amplification of oxidative stress. Additionally, the strong optical absorption in the near‐infrared II bio‐window endows MoCu DAzyme with remarkable photothermal conversion performance. Consequently, MoCu DAzyme achieves high‐efficiency synergistic cancer treatment incorporating collaborative catalytic therapy and photothermal therapy. This work will advance the therapeutic applications of DAzymes and provide valuable insights for nanocatalytic cancer therapy.

Bimetal anchoring porous MXene nanosheets for driving tandem catalytic high‐efficiency electrochemical nitrate reduction

AbstractElectrochemical nitrate reduction reaction (NO3RR) is considered a promising strategy for ammonia synthesis and nitrate removal, in which catalyst development is crucial. Herein, a series of bimetal (Co and Cu) anchoring porous MXene nanosheets (CoxCuy@PM) catalysts were prepared by combining etching and reduction strategy. On the one hand, Cu and Co bimetals provided tandem catalytic active sites for NO3RR. On the other hand, the in‐plane PM exhibited good electrical conductivity and multiple transport pathways. Consequently, the optimized Co7Cu3@PM catalyst achieved a high ammonia yield of 7.43 mg h−1 mg cat.−1 and an excellent Faraday efficiency (FE) of 95.9%. The mechanism of NO3RR was investigated by analyzing electrolysis products and in situ Fourier transform infrared spectroscopy. Furthermore, the Co7Cu3@PM based ZnNO3− battery exhibited the superior power density of 5.59 mW cm−2 and an NH3 FE of 92.3%. This work presents an effective strategy to design MXene‐based high‐performance NO3RR electrocatalysts.

Triggering Asymmetric Layer Displacement Polarization and Redox Dual-Sites Activation by Inside-Out Anion Substitution for Efficient CO2 Photoreduction.

Sluggish bulk charge transfer and barren catalytic sites severely hinder the CO2 photoreduction process. Seeking strategies for accelerating charge dynamics and activating reduction and oxidation sites synchronously presents a huge challenge. Herein, an inside-out chlorine (Cl) ions substitution strategy on the layered polar Bi4O5Br2 is proposed for achieving layer structure-dependent polarization effect and redox dual-sites activation. Cl ions in the bulk phase shrink the halogen layer interspace by 8‰, triggering asymmetric [Bi4O5]2+ layer displacement polarization, prolonging the average photocharge lifetime to 201.8ps. Meanwhile, surface substituted Cl ions enhance the electron-donating capability of neighboring Bi atoms, activating the intrinsic Bi reduction sites, and increasing H2O molecule adsorption on nearby intrinsic O oxidation site (cal. by 0.105eV), also self-donating as an alien oxidation site. Besides, Cl upshifts the p-band center closer to the Fermi level, facilitating the reactant adsorption. Therefore, the energy barrier for CO2 activation and rate-limiting *COOH intermediate formation steps are significantly decreased. Without cocatalysts and sacrificial reagents, inside-out Cl-substituted Bi4O5Br2 delivers a remarkable CO2-to-CO photoreduction rate of 50.18µmol g-1 h-1, being one of the state-of-the-art catalysts. This finding offers insights into exploiting polarization at the molecular-level and enhances understanding of catalytic site activation.

Atomic Level Understanding of the Structural Stability and Catalytic Activity of Nanoporous Gold/Titania Cluster Inverse Catalysts at Ambient and High Temperatures.

Nanoporous gold (NPG) exhibits exceptional catalytic performance at low temperatures, but its activity declines at elevated temperatures due to structural coarsening. Loading metal oxide nanoparticles onto NPG can enhance its catalytic activity at high temperatures. In this work, we used NPG-supported titania nanoparticles as a model system (denoted as Ti2O4/NPG) to study their catalytic activity at ambient and high temperatures with CO oxidation as a probe reaction by density functional theory (DFT) calculation and ab initio molecular dynamics (AIMD) simulations. The possible factors that may affect the CO oxidation reaction pathways and energy profiles on the Ti2O4/NPG, such as oxygen vacancies; silver impurities; Mars-van Krevelen (MvK), Eley-Rideal (ER), or trimolecular Eley-Rideal (TER) mechanisms; and catalytic active sites, were comprehensively investigated. The results showed that reaction energy barriers on Ti2O4/NPG were not significantly decreased compared to the pristine NPG, indicating that their catalytic activities at ambient temperature were comparable. At the evaluated temperature (400 °C), the Ti2O4/NPG exhibited superior thermal stability and maintained its active sites, while the NPG reduced active sites due to surface coarsening. The strong oxide-metal interaction (SOMI) effect between the NPG and Ti2O4 nanoparticles is found to be a main factor for the high structural stability and catalytic activity at high temperatures.

Discovery of 5-(Substituted Phenyl)-2-aryl Benzimidazole Derivatives as SIRT1 Activators: Their Design, in silico Studies, Synthesis, and in vitro Evaluation.

Silent information regulator two homologue one (SIRT1) is an emerging target for managing metabolic disorders. This study aimed to synthesize novel 5-(- substituted phenyl)-2-aryl benzimidazole derivatives and evaluate them for SIRT1 activation. The compounds were designed according to the findings of the QSAR models framed in our previous studies. Molecular docking and dynamics studies were also performed to explore the interactions of designed compounds with the active site of the SIRT1 enzyme using AutoDock Vina and Schrödinger Maestro version 11.8.012, respectively. Compounds with good binding affinity were synthesized by Suzuki-Miyaura cross-coupling and spectrally characterized. The molecules were evaluated for their in vitro SIRT1 activation properties using a fluorescent screening kit. Based on the results of in vitro assay, a structure-activity relationship was established. SwissADME was employed to calculate the pharmacokinetics characteristics of the synthesized molecules. The molecular docking studies revealed that all the activators were effectively docked in the catalytic active site. All compounds demonstrated interactions with important amino acids like Glu230 and Arg446. In molecular dynamics simulations, the root mean square deviation (RMSD) of compound 5m and protein SIRT1 remained stable, i.e., below 3mm. Compound 5m, 4-(2-(3,4-dihydroxy-5-nitrophenyl)-1H-benzo[d]imidazol- 5-yl)benzaldehyde, was the most potent compound with an EC50 value of 0.006 mM (±0.001) and maximum activation of 240.5%. All the synthesized compounds had acceptable theoretical ADME profiles, and drug-likeness properties complied with Lipinski's rule. According to the findings, synthesized compounds may be viable leads for SIRT1 activators and may be used to advance preclinical in vivo research utilizing animal models.

Elaborate construction of a MOF-derived novel morphology Z-scheme ZnO/ZnCdS heterojunction for enhancing photocatalytic H2 evolution and tetracycline degradation

Elaborate construction of novel Z-scheme heterojunction with exceptional morphology derived from metal-organic framework (MOF) have been attracted greatly interest for improving the photocatalytic ability. Herein, a Z-scheme ZnO/ZnCdS heterojunction of rare morphology with ultrathin-nanosheet assembled hierarchical morphology ZnCdS supporting on rich gap ZnO nanospheres were constructed from Zn-based MOF (namely PZH-139) for the first time. This unique feature increased specific surface area, offered abundant mass transport channels and accessible catalytic active sites, accelerated electron migration, which highly elevated photocatalytic property. Furthermore, electron paramagnetic resonance (EPR) measurements and density functional theory (DFT) calculations confirmed the reservation of strong redox capability owing to Z-scheme electron transfer path and the ΔGH* closer to zero of Z-scheme ZnO/ZnCdS system were another two key factors for boosting the photocatalytic activity. As a result, 3-ZnO-700/ZnCdS-160 with optimal morphology showed the best H2 generation performance of 15.43 mmol h−1 g−1 and degradation tetracycline (TC) efficiency of 98.14 %. This work offered a novel and feasible idea for elaborate synthesis of the high-efficiency Z-scheme ZnO/ZnCdS heterojunction with special morphology derived from Zn-MOF.

Pd nanoparticles on DUT-67-PZDC-derived N-doped carbon for efficient H2 generation from formic acid dehydrogenation

It is important to develop heterogeneous catalysts with high efficiency and stability to catalyze formic acid (FA, HCOOH) dehydrogenation. Herein, through pyrolysis of DUT-67-PZDC and etching in a hydrofluoric acid (HF) solution, the HF-etched N-doped carbon (HNDC) carrier was obtained. Palladium nanoparticles (Pd NPs), with an average particle size of 3.0 nm, were prepared on the HNDC support using a simple chemical co-reduction method. The optimized Pd/HNDC catalyst demonstrates excellent catalytic activity, the initial turnover frequency (TOF) value is 6001 h−1 at 50 °C with the incorporation of sodium formate (SF) as an additive, and the FA conversion and hydrogen (H2) selectivity could be up to 100%, which is comparable to the majority of MOF-derived heterogeneous catalysts published to date. Additionally, the Pd/HNDC can maintain good stability in five consecutive FA dehydrogenation runs with only a slight decrease. Such remarkable catalytic performance of Pd/HNDC is mainly ascribed to the unique structure of HNDC support with high surface area and hierarchical pore characteristic, the strong synergistic interaction between Pd NPs and the N sites on HNDC, as well as the ultrasmall size and high dispersion of Pd NPs as the catalytic active site. This work offers an efficient method for assembling highly active catalysts for FA dehydrogenation.