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[Display omitted] • CoII and MnII dithiocarbamate adducts were synthesized and characterized. • They were used as catalysts in hydrogen-evolution electrocatalysis. • Rate constants of 2.02–4.54 s−1 were observed for their catalytic processes. • They yielded theoretical rate constant k cat of 757 and 1526 M−1s−1 respectively. • They exhibit good catalytic activity via the dominant confirmatory ECEC mechanism. In this study, 1,10-phenanthroline adducts of bis(N - para -carboxyphenyldithiocarbamato)-cobalt (II) (1) and manganese (II) (2) possessing CoII/I and MnII/I redox couples at −1.56 and −1.57 V versus Ag/AgCl reference were carefully synthesized. These complexes are active for proton reduction at relatively low overpotentials of 0.12 – 0.32 V. Adduct 1 displayed metal-centered catalytic currents at −1.52, −1.58, −1.65, and −1.79 V at [TFA] of 1–4 mM culminating in an anodic shift of 40 mV and cathodic shifts of 20, 90, and 230 mV while adduct 2 displayed metal-centered catalytic currents at −1.53, −1.61, −1.85, and −1.89 V at [TFA] of 3–5 mM culminating in an anodic shift of 40 mV and cathodic shifts of 40, 280, and 320 mV. Experimental TOFs (k obs) of 2.02–4.54 s−1 were observed for the metal-centred processes while the foot-of-the-wave analysis (FOWA) which was used to examine the kinetics of electrocatalysis yielded theoretical TOFs of 0.45 and 0.92 s−1 that culminated in rate constants k cat of 757 and 1526 M−1s−1 for adducts 1 and 2 respectively. The controlled potential electrolysis produced TONs and Faradaic efficiencies in the range of 2.9–5.5 and 61–88 % respectively. The outstanding performances of the adducts offer promising prospects for the electrocatalytic reduction of protons. [ABSTRACT FROM AUTHOR]

• Two new rhombic-shaped Ln 4 compounds have been synthesized and structurally characterized. • The Ln 4 compounds exhibit good catalytic performances for cycloaddition of CO 2 with epoxides. • The Ln 4 compounds also exhibit good catalytic performances for knoevenagel condensation under mild condition. Two Ln 4 clusters with the formula of [Ln 4 (acac) 4 (µ 3 OH) 2 (L) 6 ]·xCH 3 CN (Ln=Sm (1), Yb (2)) were synthesized through the reaction of Ln(acac) 3 ·2H 2 O (Hacac = acetylacetone) with the bidentate flexible ligand 5-benzylidene-1,5-dihydroquinolin-8-ol. X-ray diffraction studies indicate that clusters 1 and 2 are isostructural and processes a rhombic-shaped Ln 4 core. The coordination geometry of each Ln(III) ion is characterized as a distorted square antiprism. Notably, clusters 1 and 2 exhibit outstanding catalytic performance for the cycloaddition of CO 2 with epoxides and for Knoevenagel condensation under mild conditions. Two rhombic-shaped Ln 4 clusters exhibit good catalytic performances for cycloaddition of CO 2 with epoxides and Knoevenagel condensation under mild condition, simultaneously. [Display omitted] [ABSTRACT FROM AUTHOR]

Volatile organic compound (VOC) abatement has become imperative nowadays due to their harmful effect on human health and on the environment. Catalytic oxidation has appeared as an innovative and promising approach, as the pollutants can be totally oxidized at moderate operating temperatures under 500 °C. The most active single oxides in the total oxidation of hydrocarbons have been shown to be manganese and cobalt oxides. The main factors affecting the catalytic performances of several metal-oxide catalysts, including CoOx and MnOx, in relation to the total oxidation of hydrocarbons have been reviewed. The influence of these factors is directly related to the Mars–van Krevelen mechanism, which is known to be applied in the case of the oxidation of VOCs in general and hydrocarbons in particular, using transitional metal oxides as catalysts. The catalytic behaviors of the studied oxides could be closely related to their redox properties, their nonstoichiometric, defective structure, and their lattice oxygen mobility. The control of the structural and textural properties of the studied metal oxides, such as specific surface area and specific morphology, plays an important role in catalytic applications. A fundamental challenge in the development of efficient and low-cost catalysts is to choose the criteria for selecting them. Therefore, this research could be useful for tailoring advanced and high-performance catalysts for the total oxidation of VOCs. [ABSTRACT FROM AUTHOR]

Carbon dots (CDs) have uniquely structural, physicochemical and photochemical properties, suggesting a promising platform for catalysis applications. The in-depth understanding of the structure-activity relationship in the CDs-based catalyst system needs to know the effect of the crystalline core on their catalytic performance. The efficient catalytic oxidation of cyclohexane is an urgent challenge in current chemical industry, in which, adipic acid (AA) plays an important role in industry for synthesis of nylon-6 and nylon-66. Here, we fabricated the pristine CDs by electrochemical etching graphite rod method and derived CDs with high crystalline core (CD-600, CD-800, and CD-1100) through a thermal treatment method in tube furnace. Furthermore, these CDs performed an outstanding catalytic performance for one-step synthesis of AA from cyclohexane. With the help of machine learning (ML), the deep correlations between features (structures of CDs, catalytic conditions) and catalytic performances were investigated by XGBoost (XGB) model. Then under the optimization and prediction of XGB, it was found that high crystalline core preceded the other features and CD-1100 could get the best conversion of 30.696% and selectivity to AA of 92.52% at reaction conditions of 130 °C, 1.5 MPa, and 10 h. This work pioneered the application of ML in industrial issues and demonstrated a comprehensive understanding on CDs as catalyst to realize one-step synthesis of AA. [ABSTRACT FROM AUTHOR]

Oxygen evolution reaction (OER), as a relevant half reaction for water splitting to address the energy crisis, has captured a great deal of attention. However, this technology has always been impeded by the lack of a highly efficient and stable electrocatalyst. Amorphous materials, which possess long‐range disorder and only short‐range order over a few atoms, are often superior to their crystalline counterparts in electrocatalysis owing to their more active sites, broader chemical composition range, and more structural flexibility. This review first introduces some assessment criteria for the OER and then presents theoretical modeling of the OER mechanisms and the state‐of‐the‐art amorphous transition metal‐based OER electrocatalysts, involving oxides, hydroxides, sulfides, phosphides, borides, and their composites, as well as their practical applications in the OER. Finally, recent development, existing challenges, and future perspectives for amorphous transition metal‐based OER electrocatalysts are discussed. This paper offers valuable guidance in designing highly efficient and stable amorphous OER electrocatalysts for future energy applications. [ABSTRACT FROM AUTHOR]

While tremendous advances have been made in dimensionality-dependent performances of inorganic-based low-dimensional nanostructures, paradigms concerning p-conjugated molecule-based supramolecular nanoassemblies are relatively fewer despite their various intrinsic advantages. It is herein reported that 0D, 1D, and 2D supramolecular nanostructures of a porphyrin, 5,10,15,20-tetrakis(4-aminophenyl)-21H,23H-porphine, with a spherical, fibrous and sheetlike architecture, respectively, could be fabricated via a reprecipitation protocol. As a typical example to demonstrate their dimensionality-dependent optoelectronic performances, it is shown that the nanomaterials could serve as photocatalysts for water remediation, where the catalytic reactivity exhibits a trend of nanofibers>nanospheres>nanosheets. The superior catalytic reactivity of the nanofibers stems from the formation of relatively well-defined J-aggregates with orderly and tightly organized chromophores, conferring them with strong photoinduced electron-hole transport and separation capability. The higher catalytic reactivity of the nanospheres than nanosheets results from their larger specific surface area, which facilitates efficient accessibility of photogenerated charge carriers, although the porphyrins therein form unspecific J-aggregates with disorderly and loosely stacked chromophores. The investigation likely initiates a simple method for p-conjugated molecule-based 0D, 1D and 2D nanoassemblies by using the same tectons, based on which the highlighted underlying scientific insights might provide useful clues for rational design of organic-based low-dimensional advanced soft materials. [ABSTRACT FROM AUTHOR]

As one of the promising clean and renewable technologies, water splitting has been a hot topic, especially the half‐reaction of oxygen evolution reaction (OER) due to its sluggish and complex kinetics. Hence, Fe‐doped NiCo2O4 nanobelts were designed and prepared as catalysts toward OER. By increasing the Fe amount, the catalytic performances of the as‐synthesized products went up and then decreased. Profiting from the synergistic effect between Fe atom and NiCo2O4, all the Fe‐NiCo2O4 catalysts exhibited superior catalytic activities to the corresponding NiCo2O4. In addition, the characteristic nanobelt architecture facilitates the conduction of electrons and the exposure of active sites. With the optimal Fe content, the 9.1 % Fe‐NiCo2O4 yielded the smallest overpotential and Tafel slope among the catalysts, distinctly lower than that of RuO2. [ABSTRACT FROM AUTHOR]

In this study, NiCo 2 O 4 with different morphologies were fabricated using carriers by homogeneous coprecipitation combined with a sintering method. The phase and microstructure were characterized by XRD, SEM, EDS, TEM and BET, and the catalytic performances were investigated by NaBH 4 hydrolysis experiments. These studies revealed that the deposition morphology of NiCo 2 O 4 can be adjusted by using different kinds of carrier templates, and the supported NiCo 2 O 4 samples presented the pine-needle-like, network-like, ball-cactus-like and dandelion-like morphologies respectively. The optimal catalytic activity, durability and stability make the network-like NiCo 2 O 4 an appropriate catalyst for hydrogen generation of NaBH 4 hydrolysis. It was found that the network-like NiCo 2 O 4 is the most reusable and durable catalyst for ten consecutive cycles and 100% hydrogen generation conversion rate without obvious decrease among these morphologies. [ABSTRACT FROM AUTHOR]

Abstract A Sb/palygorskite (PAL) composite was synthesized by a facile solvothermal process and applied in catalytic hydrogenation of p-nitrophenol for the first time. It was found that the Sb nanoparticles with the sizes of 2–5 nm were well dispersed on the fiber of PAL, while partial aggregated Sb nanoparticles with sizes smaller than 200 nm were also loaded on the PAL. The Sb/PAL composite with 9.7% Sb mass amounts showed outstanding catalytic performance by raising the p-nitrophenol conversion rate to 88.3% within 5 min, which was attributed to the synergistical effect of Sb and PAL nanoparticles facilitating the adsorption and catalytic hydrogenation of p-nitrophenol.

Hierarchical MFI zeolites with open pores were synthesized by a temperature programmed dissolution-recrystallization post-treatment. By controlling the temperature of post-treatment using TPAOH, open macropores and mesopores were created by simply regulating the kinetics of dissolution and recrystallization. Benzyl alcohol self-etherification reaction, which only occurs in micropores, was tested on ZSM-5 to understand the effect of hierarchical pore system. The catalytic activity of hierarchical TS-1 was tested with cyclohexanone ammoximation. Hierarchical ZSM-5 and TS-1 zeolites with open pores showed higher catalytic activity compared with both hollow and conventional ones. The increased catalytic activities can be ascribed to the enhanced diffusion. [ABSTRACT FROM AUTHOR]

As an efficient method to improve the intrinsic properties of carbon quantum dots (CQDs), doping CQDs with heteroatoms including nonmetallic atoms and metal ions recently receive great attention. Since the summary about the achievements of CQDs doping with nonmetallic atoms has been carried out. In this minireview, we will overview the state-of-the-art knowledge of metal ions doped-CQDs (M-CQDs). The synthetic routes for M-CQDs, the novel physicochemical properties originating from their unique morphology and constitute, and their applications in environmental, biological and energy-related areas will be summarized and highlighted. The review aims to provide new insights into the exploration of the methods in order to improve the functionality of M-CQDs, the relationship between newly novel physicochemical properties and metal ions doping, as well as their possible applications in future. [ABSTRACT FROM AUTHOR]

Hierarchical flower-like cobalt tetroxide (Co 3 O 4 ) was successfully synthesized via a facile precipitation method in combination with heat treatment of the cobalt oxalate precursor. The samples were systematically characterized by thermo gravimetric analysis and derivative thermo gravimetric analysis (TGA-DTG), X-ray powder diffraction (XRD), field-emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM) and N 2 adsorption-desorption measurements. The results indicate that the as-fabricated Co 3 O 4 exhibits uniform flower-like morphologies with diameters of 8–12 μm, which are constructed by one-dimensional nanowires. Furthermore, catalytic effect of this hierarchical porous Co 3 O 4 on ammonium perchlorate (AP) pyrolysis was investigated using differential scanning calorimetry (DSC) techniques. It is found that the pyrolysis temperature of AP shifts 142 °C downward with a 2 wt% addition content of Co 3 O 4 . Meanwhile, the addition of Co 3 O 4 results in a dramatic reduction of the apparent activation energy of AP pyrolysis from 216 kJ mol −1 to 152 kJ mol −1 , determined by the Kissinger correlation. The results endorse this material as a potential catalyst in AP decomposition. [ABSTRACT FROM AUTHOR]

Zeolite Y with intracrystalline mesopores has been synthesized by controlling a ternary balance (chemical anchoring of the template on zeolite framework, mesoporous self-assembly around the template, and crystallization of zeolite Y). The rapid hydrolysis of (CH 3 O) 3 Si- to -Si-OH and the subsequent linkage to zeolite framework were crucial for the formation of intracrystalline mesopores. The high concentration of OH- in the initial systems favors the self-assembly of well-ordered mesophases due to the high stability of Dimethyloctadecyl[3-(trimethoxysilyl)propyl]ammonium chloride (TPOACl) micelles. The well-ordered mesopores transfer to wormlike because the solubility of TPOACl increase with the decreased alkalinity by prolonging crystallization of zeolite Y. The materials with relatively well crystallized zeolite Y and high mesopores surface area showed better catalytic properties than the conventional Y and alone well-ordered mesoporous materials. The obtained sample exhibited improved catalytic performance in heavy oil cracking. The yield of the light fraction (gasoline + diesel) of the Cat-2 catalysts is 63.4 wt%, much higher than that of Cat-1 (49.9 wt%) and the Coke yield of Cat-2 is 12.1%, much lower than that of Cat-3 (15.2%). [ABSTRACT FROM AUTHOR]

A Sb/palygorskite (PAL) composite was synthesized by a facile solvothermal process and applied in catalytic hydrogenation of p-nitrophenol for the first time. It was found that the Sb nanoparticles with the sizes of 2-5 nm were well dispersed on the fiber of PAL, while partial aggregated Sb nanoparticles with sizes smaller than 200 nm were also loaded on the PAL. The Sb/PAL composite with 9.7% Sb mass amounts showed outstanding catalytic performance by raising the p-nitrophenol conversion rate to 88.3% within 5 min, which was attributed to the synergistical effect of Sb and PAL nanoparticles facilitating the adsorption and catalytic hydrogenation of p-nitrophenol. [ABSTRACT FROM AUTHOR]

A green self-redox reaction for Rh-polypyrrole (PPy)-RGO has been triggered between Rh metal salts, graphene oxide (GO) and pyrrole without surfactant. The morphology and structure of the novel Rh-PPy-RGO hybrids with 4 nm Rh nanoparticle shows the highly increased catalytic performances for the chemical reduction reaction of p-nitrophenol (4-NP) by ammonia borane (AB, NH3BH3). In addition, a series of noble metal-PPy-RGO hybrids are successfully fabricated, such as Pt-, and Pd-PPy-RGO nanocomposite. [ABSTRACT FROM AUTHOR]

Ruthenium (Ru) featured with an unusual catalytic behavior is of great significance in several heterogeneous and electro-catalytic reactions. The preparation of tractable Ru nanocatalysts and the building of highly active catalytic system at ambient temperature remains a grand challenge. Herein, a facile strategy is developed for the controllable preparation of Ru nanoparticles (NPs) with the sizes ranging from 2.6 to 51.5 nm. Ru NPs show superior size-dependent catalytic performance with the best kinetic rate constant as high as −1.52 min −1 , which could far surpass the other traditional noble metals. Ru NPs exert exceedingly efficient low-temperature catalytic activity and good recyclability in the catalytic reduction of nitroaromatic compounds (NACs) and azo dyes. The developed catalytic system provides a distinguishing insight for the artificial preparation of Ru NPs with desired sizes, and allows for the development of rational design rules for exploring catalysts with superior catalytic performances, potentially broadening the applications of metallic NP-enabled catalytic analysis. [ABSTRACT FROM AUTHOR]

The liquid phase acylation of 2-methylfuran with acetic anhydride over modified Hβ zeolite was first conducted in a continuous flow reactor. The deactivation of Hβ zeolites was attributed to strong adsorption of reactants or products and was verified by GC-MS and C MAS NMR. Deactivated zeolites can be regenerated to their original state by calcination. The acidic properties was adjusted by surface modification on Hβ, the maximum yield of 89.5 mol% and selectivity of 100 % were obtained over tartaric acid modified by Hβ. The deposition of tetraethoxysilane to silica on Hβ contributed to enhancing the catalytic stability. Combined with the results of NH-TPD and Py-FTIR, the amount of Broensted acids played a major role on catalytic activity. A close relationship between the catalytic stability and the ratio of the amount of strong to weak acids at 1:1 was highlighted here. The solvents' effect on the catalytic performances was examined, and 1,2-dichloroethane with moderate polarity exerted a positive effect on catalytic stability. [ABSTRACT FROM AUTHOR]

Versatile Co 3 O 4 nanocubes made up of abundant nanoparticles with a mean size of ∼25 nm were reported here. A precursor with a cubic shape was firstly prepared by a simple solvothermal process; and then porous Co 3 O 4 nanocubes were obtained through calcining the cubic precursor. The as-obtained products were characterized by X-ray powder diffraction, scanning electron microscopy, and (high resolution) transmission electron microscopy. Experiments showed that the as-obtained porous Co 3 O 4 nanocubes presented good electrochemical property in 0.1 mol L −1 KOH solution and could be used as an electrochemical sensor for the detection of glucose. The corresponding detection limit was calculated to be 0.77 μM. Also, the as-obtained Co 3 O 4 nanocubes owned excellent photocatalytic activity. Under the irradiation of 365 nm UV light, 97.8% Pyronine B and 98.2% Safranine T were degraded within 3 h. Moreover, the as-obtained product still exhibited an outstanding catalytic ability for the thermal decomposition of ammonium perchlorate (AP). Before and after the addition of 2 wt% Co 3 O 4 , the decomposition temperature of AP decreased from 478 °C to 275 °C. The above facts indicated that the as-prepared porous Co 3 O 4 nanocubes had extensive applications as potential multifunctional catalysts in many fields. [ABSTRACT FROM AUTHOR]

Two novel series of binuclear metal phthalocyanines M(PcHb) and M(PcHb)C (M = Co(II), Mn(II), Fe(II), Ni(II), and Cu(II)) were designed and synthesized as high-efficiency catalysts for lithium/thionyl chloride (Li/SOCl) battery. For the sake of preparing the novel compounds, a simple and convenient method called microwave irradiation was developed. Numerous techniques including elemental analysis, Fourier transform infrared, ultraviolet-visible, and thermal gravimetric analysis were employed to characterize the final products. For the purpose of evaluating the catalytic performances of binuclear metal phthalocyanines to Li/SOCl battery, these compounds were operated in the electrolyte of the battery. The results revealed that the capacity of the battery had been improved approximately 15.4-46.1 %, which should be attributed to the electronic configurations of the metal ions, the phthalocyanine rings, and the synergistic effect. Among the effects of diverse metal ions on the catalytic performances of binuclear phthalocyanines, Co(II) and Ni(II) phthalocyanines were found to increase the catalytic performances to a great extent, approximately 45.1 and 46.1 %, respectively. In summary, all the evidences testified that binuclear metal phthalocyanines in this study could improve the catalyst performances dramatically when they were operated in the electrolyte of the battery. [ABSTRACT FROM AUTHOR]

• Atomically dispersed metal heterogeneous catalysts (ADHCs) are reviewed. • ADHCs include supported metal complexes, single atom catalysts and single atom alloys. • Relationship of coordination structure of metal and performance of ADHCs is discussed. • Both thermocatalysis and electrocatalysis (ORR, CO 2 activation) are investigated. • Thermocatalysis reactions include hydrogenation, CO oxidation, C–H activation, etc. Atomically dispersed metal heterogeneous catalysts (ADHCs) possessing maximum metal dispersion have attracted extensive attentions in material and energy-related fields. Previous studies mainly focused on the material synthesis and characterization of the ADHC, while the relation between material structures and performances is rarely addressed. To understand the structure-performance relationship in this type of catalysts at atomic scale, we focus, in this review, on the recent studies of the coordination environment and how it affects the performances of atomically dispersed metal heterogeneous catalysts. We consider supported atomically dispersed metal complexes, atomically dispersed metal/metal oxide catalysts and single atom alloy catalysts, evaluating performance in both thermocatalysis and electrocatalysis. This review aims to build the relationship existed between the coordination structures of the metal single atoms and the performances of the atomically dispersed catalysts. We also provide a perspective to guide the future development of this field. [ABSTRACT FROM AUTHOR]

The preparation of Au-on-Pd heteronanostructure (HNS) using citrate-stabilized polycrystalline Pd nanoparticles (NPs) as the seeds is described. The resulting Au-on-Pd HNS is characterized and it is found that the formation of Au-on-Pd HNS depends greatly on a ratio between Pd seeds and AuCl4− ions added and the optimal molar ratio is 10:1. If fewer AuCl4− ions are added (Pd/Au ratio is 100:1), the growth of Au NPs only occurs on part of the Pd seeds' surface. The addition of more AuCl4− ions (Pd/Au ratio is 5:1) hinders the growth of Au NPs on the Pd seeds' surface. To demonstrate the catalytic performance, the electrochemistry oxidation of ethanol and the reduction of p-nitrophenol by NaBH4 are chosen to examine the catalytic activity of Au-on-Pd HNS. Pd seeds, Au NPs, and poly(vinyl pyrrolidone) (PVP)-stabilized PdAu nanoalloy are used as the references for comparison. In the first reaction, the catalytic reactivity of Au-on-Pd HNS is better than that of corresponding pure Pd or Au NPs, while the opposite occurs for the latter reaction. The catalytic activity of Au-on-Pd HNS is much higher than that of PVP-stabilized PdAu nanoalloy. [ABSTRACT FROM AUTHOR]

SO/Al-O-MCM-41 solid acid catalysts were prepared by the sol-gel method. Their catalytic performances were evaluated by the esterification reaction of acetic acid with n-butanol. The characterization of prepared catalysts was performed by means of XRD, IR, TG-DSC and SEM. The experimental results showed that the SO/Al-O-MCM-41 solid acid catalyst exhibited an optimal catalytic performance with ca. 99.00 % esterification efficiency under the optimum synthesis conditions. In addition, it kept its high activity with 93.17 % esterification efficiency even after being used for seven times, which indicated that SO/Al-O-MCM-41 solid acid catalyst had excellent reusability. [ABSTRACT FROM AUTHOR]

New types of SO/Al- x wt%Ce-Zn-O solid acid catalysts were prepared by the sol-gel method. Their catalytic performances for the synthesis of n-butyl acetate from acetic acid and n-butanol were investigated. The characterization of prepared catalysts was performed using XRD, IR, TG-DSC and SEM. The experimental results showed that the SO/Al-2.5 wt%Ce-Zn-O solid acid catalyst exhibited an optimal esterification performance with 98.71% esterification efficiency under the optimum synthesis conditions. Moreover, the SO/Al-2.5 wt%Ce-Zn-O solid acid catalyst retained its high activity with above 95% esterification efficiency after being used repeatedly for seven times, which indicated that the SO/Al-2.5 wt%Ce-Zn-O solid acid catalyst had excellent stability. [ABSTRACT FROM AUTHOR]

A comparative study on the effects of alkali metal on the structures, physico-chemical properties and catalytic behaviors of silica-supported vanadium catalysts for the selective oxidation of ethane and the complete oxidation of diesel soot was reported. [ABSTRACT FROM AUTHOR]

[Display omitted] • Recent advances of antibacterial nanozymes are overviewed. • The antibacterial mechanisms and influencing factors regarding the antibacterial activities of nanozymes are given. • Various types of nanozymes for antibacterial, anti-biofilms, and biofouling are summarized. • The biosafety profiles of antibacterial nanozymes are analyzed. • Current challenges in the clinical translation process and future perspectives of antibacterial nanozymes are discussed. Topics of bacterial resistance have attracted remarkable scientific interests. Bacterial infection-related diseases are major public safety issues that lead to millions of deaths annually. Therefore, it is urgent to develop novel, high efficiency, and bacteria-binding antibacterial agents. As far as now, the emergence of nanozymes has been presented as promising candidates to combat bacteria. Combining the advantages of nanomaterials and natural enzymes, such nanozymes are generally low cost, good stability, controllable size, easy-of-preparation, multifunctionality, and superior catalytic activity. As the potent antibacterial agents, nanozymes possess satisfying broad-spectrum antibacterial abilities and biocompatibility. Herein, we timely summarize the recent research progress of different kinds of nanozyme-based antibacterial agents. Additionally, the relevant antibacterial mechanisms of nanozymes and the roles of physicochemical properties, external stimuli, and surface modifications on their catalytic performances and biosafety are also discussed. Finally, current challenges and the future perspectives are covered to stimulate new strategies and more effective nanozyme-based antibacterial agents for preclinical translations. [ABSTRACT FROM AUTHOR]

As one of the promising clean and renewable technologies, water splitting has been a hot topic, especially the half-reaction of oxygen evolution reaction (OER) due to its sluggish and complex kinetics. Hence, Fe-doped NiCo 2 O 4 nanobelts were designed and prepared as catalysts toward OER. By increasing the Fe amount, the catalytic performances of the as-synthesized products went up and then decreased. Profiting from the synergistic effect between Fe atom and NiCo 2 O 4 , all the Fe-NiCo 2 O 4 catalysts exhibited superior catalytic activities to the corresponding NiCo 2 O 4 . In addition, the characteristic nanobelt architecture facilitates the conduction of electrons and the exposure of active sites. With the optimal Fe content, the 9.1 % Fe-NiCo 2 O 4 yielded the smallest overpotential and Tafel slope among the catalysts, distinctly lower than that of RuO 2 ., (© 2020 Wiley-VCH GmbH.)

In this paper, a simple route for palladium (Pd) nanoparticles attached to the surface of hollow magnetic Fe3O4/P (GMA‐DVB)‐polyethyleneimine (PEI) microspheres was established. Due to the large amount of imidogen groups and tertiary amine groups presenting in the PEI, Pd2+ ions could be anchored to the support by complexation with a polyfunctional organic ligand. Thereafter, a magnetic Pd catalyst having a high loading amount and good dispersibility was obtained by reducing Pd2+ ions. Afterwards, the prepared catalyst was characterized by TEM, SEM, FTIR, XRD, TGA, VSM, and UV–vis in detail. Ultimately, their catalytic activity was evaluated using the reduction of 4‐nitrophenol (4‐NP). Research showed that the Fe3O4/P (GMA‐DVB)‐PEI/Pd catalyst possessed high catalytic performances for the reduction of 4‐NP with a conversion rate of 98.43% within 540 s. Furthermore, the catalyst could be easily recovered and reused at least for nine successive cycles. [ABSTRACT FROM AUTHOR]