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Mechanism of PMS activation by the MPCBs/PMS system. [Display omitted] Magnetic carbon-based catalysts are promising materials for advanced oxidation processes, offering both high catalytic activity and environmental friendliness, and hold great potential in environmental remediation. In this work, Fe and Co zeolite imidazole frameworks (ZIFs) derived micron-sized magnetic porous carbon beads (MPCBs) were prepared by phase inversion and following the carbonization procedure, and the morphological and structural characteristics of the MPCBs were confirmed. The presence of pores and channels in the MPCBs provides a specific microenvironment for the for the catalysis of the core. Bisphenol A (BPA) was selected for the targeted pollutant, and the catalytic experiments confirmed that the effective catalytic activity of MPCBs in the presence of peroxymonosulfate (PMS), which could almost completely degrade BPA in 20 min with a reaction rate of 0.368 min−1. Furthermore, the MPCBs were used to effectively bacterial inactivation. Intermediate products of the BPA degradation process were validated and the toxicological studies showed a gradual decrease in toxicity, indicating effective reduction of potential hazards. The macroscopic preparation methods we developed for MPCBs that is promising for industrial applications and has the potential to cope with complex environmental remediation. [ABSTRACT FROM AUTHOR]

As a class of metal‐organic framework, the zeolitic‐imidazole framework‐67 is constructed from bridging cobalt ions and 2‐methylimidazole. The high content of abundant active cobalt species, uniform structure, ultrahigh porosity, and large surface area show the potential for multiple catalytic applications, especially electrocatalytic oxygen evolution reaction (OER). The design and synthetic strategies of catalyst‐based ZIF‐67 that approach the maximized catalytic performance are still challenging in further development. Herein, the current progress strategy on the structural design, synthetic route, and functionalization of electrocatalysts based on ZIF‐67 to boost the catalytic performance of OER is reviewed. Besides, the structurally designed catalyst from various fabricated strategies corresponding to enhancing catalytic activity is discussed. The emphasized review for understanding design and synthetic structure with catalytic performance could guide researchers in further developing catalyst‐based ZIF‐67 for improving the efficient electrocatalytic OER. [ABSTRACT FROM AUTHOR]

Novel B-doped NiP/Hβ (Hβ is the hydrogen proton exchanged β molecular sieve) catalysts were prepared and the catalytic performance for n-C6 (n-hexane) isomerization was studied firstly. It was found that the mole ratio of Ni, P and B in preparing B-doped NiP had important influence on the crystalline structure and catalytic activity of NiPB. When the mole ratio of Ni, P and B was 1:1:1, the prepared NiPB was amorphous and NiPB/Hβ had the best catalytic activity with the conversion rate of n-C6, the yield and selectivity of isoparaffins being 79.93%, 78.34% and 98.01% respectively. It was also showed that the preparation conditions of catalyst including NiPB loading on carrier and calcination temperatures were the key factors for the catalytic performance of NiPB/Hβ. In controlled experiments, ammonia poisoned acid sites on the catalyst led to the markedly reducing of catalytic performance and metal sites were essentially for the dehydrogenation-hydrogenation reaction. The isomerization of n-C6 catalyzed by NiPB/Hβ is a continuous alternating process of acid catalysis and metal catalysis, and the matching of acid sites and metal sites is of importance. [ABSTRACT FROM AUTHOR]

A "two-in-one" dual activation strategy has been developed to give high-density hydrogen-bonding (HB) active units and Lewis acid (LA) active centres by immobilizing squaramides into metal–organic cages (MOCs). The obtained MOC served as an efficient catalyst for the chemical fixation of CO2 under mild conditions up to 99% yields with good recyclability, and the mechanism of high catalytic activity has been further explored. [ABSTRACT FROM AUTHOR]

Herein, a series of highly active K species-supported synergistically modified LaMnO3 (LM) catalysts were prepared by acid etching for soot oxidation. As shown in XRD, TEM and XPS results, appropriate etching hours could remove La atoms on A-sites and produce A-site defects without destroying the whole perovskite structure, which created more B-sites on terminated perovskite surfaces and promoted the activation of oxygen molecules through Mn4+/Mn3+ redox cycles, thus improving the catalytic activity for soot combustion. Based on this, further modification of the LM catalyst by introducing K could enhance the lower temperature reducibility of the catalyst, and promote more active oxygen species production through the interaction between potassium and LM support, thereby leading to a further improvement in catalytic performance, as confirmed according to XPS O 1s and H2-TPR results. Among all the as-prepared catalysts, the 15K/LM-2h catalyst exhibited favorable catalytic performance and stability, where the T90 values were 416 °C and 327 °C under loose and tight contact, respectively, and the Ea value was 64.2 kJ mol−1. This study provides a universal strategy for the development of high-performance catalysts for soot combustion with promising industrial application prospects. [ABSTRACT FROM AUTHOR]

• Co 2 MnGa sample exhibits both high catalytic activity and high stability for HER. • We discover a linear relationship between the ΔG H* and the areas of TSSs. • The density of TSSs at Fermi energy level can be modulated by external factors. • Transitioning topological catalysis from nonmagnetic to magnetic categories. Topological catalysis has become a major topic in electrochemical catalysis due to its outstanding performance in electrochemical reactions. Recently, a universal catalytic descriptor, known as topological surface states (TSS), has been proposed to describe catalytic performance in several nonmagnetic topological catalysts [Mater. Today 67, 23 (2023)]. However, the universality of this descriptor still lacks experimental evidence and has not been verified in magnetic topological catalysts yet. In this study, we investigate the catalytic performance and topological properties of the magnetic material Co 2 MnGa, which is a representative topological nodal chain semimetal with both theoretical and experimental validation. Our experimental findings demonstrate that Co 2 MnGa exhibits excellent catalytic performance in the hydrogen evolution reaction (HER). Our research reveals the presence of TSS from the nodal chain state is responsible for the high catalytic activity in Co 2 MnGa. Further, a direct relationship between the strength of TSS and Gibbs free energy can be built in the system. This comprehensive study has expanded our understanding of topological catalysts by exploring their material properties and corresponding topological mechanisms, extending our knowledge from nonmagnetic to magnetic categories. [ABSTRACT FROM AUTHOR]

The activity of the catalyst is closely related to the synthesis method. Hereon, we prepared a series of XMn1Cu (X = 2, 4, 6, 8) catalysts by hydrolysis driven redox, co-precipitation and hydrothermal synthesis approaches, respectively. The effect of XMn1Cu synthesized by different strategies on soot combustion activity were compared. The results show that the catalysts fabricated by hydrolysis driven redox have excellent performance than the other two methods in soot removal, and the activity follows r-XMn1Cu > h-XMn1Cu > cop-XMn1Cu. The Mn/Cu = 4:1 is the optimal ratio of Cu-Mn composite oxide. Among the materials, the r-4Mn1Cu sample has the best catalytic activity due to the uniform distribution of Mn and Cu, high specific surface area, enhanced content of Mn4+, promoted concentration of lattice defects and oxygen vacancies, and T10, T50 and T90 are 303, 355 and 386 °C, respectively. The repeated experiments present that r-4Mn1Cu has high activity and stability in soot oxidation. Combined with experimental results and characterization, oxygen vacancies and reactive oxygen generation mechanism of XMn1Cu catalyst in soot combustion were further discussed. [ABSTRACT FROM AUTHOR]

Establishing efficient nano-porous electrocatalysts for facilitating electron transfer is a one of the useful ways for enhance water splitting. Herein, Ni-Fe-Cu-Co-W high entropy alloy (NFCCW-HEA) electrocatalysts on the iron sheet substrate have been successfully prepared by a simple and efficient one-step electrodeposition method. High entropy alloys have a variety of active sites and unique atomic scale synergies, which makes the catalyst have good catalytic performance and stability. Meanwhile, the HEA coating like cauliflower by electrodeposition can provide more attachment sites, and significantly upgrade the OER catalytic activity. NFCCW-HEA catalysts exhibit an excellent overpotential of 247.3 mV under the current density of 10 mA·cm−2, and a low Tafel slope of 62.9 mV dec−1. The electrocatalyst shows long term stability of electrolysis for over 24 h in 1 mol·L−1 KOH alkaline solution, which shows good stability. We expect to provide a new idea for the preparation of nano porous high entropy alloy electrocatalysts by one-step electrodeposition technology. [Display omitted] • The nano-porous Ni-Fe-Cu-Co-W high entropy alloy electrocatalysts are prepared by a simple and efficient one-step electrodeposition method. • The formation mechanism of catalysts is carefully studied. • The unique cauliflower like nano-sheets can significantly improve the OER catalytic performance. • The synergy of multiple components • Explore different active sites [ABSTRACT FROM AUTHOR]