Hierarchical Mesoporous Structure Research Articles

Pd modified by Fe-Nx confined in N-doped carbon with hierarchical mesoporous structure for the highly efficient semi-hydrogenation of phenylacetylene

The removal of small amounts of phenylacetylene from styrene is a crucial step in the production of high-quality styrene feedstocks. In the presence of a large amount of styrene and a small amount of phenylacetylene, achieving and maintaining high selectivity of styrene remains a significant challenge. In this work, a catalyst denoted as Pd1.25-Fe-N-C/VC was designed and synthesized with remarkably low Pd loading (the actual Pd content was 0.96 wt%). The catalyst exhibited a satisfactory selectivity for styrene (>95 %) and maintained high selectivity levels (>90 %) in the semi-hydrogenation of phenylacetylene even with prolonged reaction time. Pd nanoparticles (NPs) were well distributed and securely anchored onto the Fe-N-C/VC support with a hierarchical mesoporous structure, which obtained from the pyrolysis of a hexagonal star-like Fe-doped zeolitic imidazolate framework with vitamin C surfactant (Fe-doped ZIF/VC). The remarkable catalytic properties may be partly ascribed to the effective synergy effect of the uniformly well-dispersed Fe-Nx (x represents the coordination number) with Pd active centers, which could modulate the adsorption kinetics of the reactant alkynes and alkenes and thus enhancing the selectivity towards styrene. Meanwhile, the hierarchical mesoporous structure is beneficial for the mass transfer, which can effectively promote the interactions between the reactants and active centers. Possible mechanism for the selective hydrogenation of phenylacetylene catalyzed by Pd1.25-Fe-N-C/VC was also illustrated. Moreover, the Pd1.25-Fe-N-C/VC catalyst exhibited sustained catalytic activity and selectivity even after four continuous cycle tests, showing notable reusability and stability. This work may offer a promising approach for creating highly efficient Pd-based catalysts with remarkably low Pd loading for phenylacetylene semi-hydrogenation.

Cu/Mn Synergy Catalysis-Based Colorimetric Sensor for Visual Detection of Hydroquinone

The reliable detection of environmental contaminants can correctly forecast the degree of environmental pollution that has occurred, which contributes to improving the environmental purification rate and maintaining the ecological balance. Herein, a novel hierarchical biomimetic catalysis MnO2@CuAl-CLDHs was designed and synthesized using a facile method, which exhibited significantly enhanced peroxidase-like activity due to the unique composition and hierarchical mesoporous structure. Under optimized operational conditions, a visible colorimetric array based on the superior nanozyme activity of MnO2@CuAl-CLDHs was developed for the quantitative determination of hydroquinone with a wide linear detection range (1–100 μM) and a low detection limit (0.183 μM). Simultaneously, our presented strategy could analyze hydroquinone in real water samples with high accuracy. Therefore, the bimetallic co-catalyzed nanozymes are expected to be the perfect replacement for natural enzymes to develop convenient and efficient sensors.

Nanohoneycomb rGO foam as a promising anode material for unprecedented ultrahigh Li storage and excellent endurance at ampere current stability

Most rechargeable lithium-ion batteries (LIBs) exploit bulk carbon (e.g., graphite with low interlayer spacing of 0.335 nm) as an anode material despite its low theoretical capacity of 372 mAh/g because it has a high coulombic efficiency, good cycling performance, and low production costs. However, it is difficult to increase the specific capacity of graphite-based anodes without sacrificing these inherent advantages. In the present study, we developed reduced graphene oxide nanohoneycomb foam (H-rGO) as an anode material with higher surface area, porosity, and interlayer spacing for the rapid and efficient lithiation-delithiation of Li-ions. The combination of the hierarchical three-dimensional sponge-like mesoporous structure with highly efficient Li-ion conduction pathways and enlarge active surface area leads to a significantly improved specific capacity (1031 mAh/g at 0.1 A/g) and rapid charging with exceptional stability over 5,000 cycles. The H-rGO anode achieves an outstanding reversible capacity of ∼534 mAh/g over 2,500 cycles at 1.0 A/g, with a capacity retention of 87 and 84 % at high current densities of 10 and 20 A/g, respectively. Our approach is fully compatible with current LIBs technology and offer a simple and efficient strategy to significantly increase Li-storage capacity of under current graphite-based anode technology.

Urchin-like Ce(HCOO)3 Synthesized by a Microwave-Assisted Method and Its Application in an Asymmetric Supercapacitor.

In this work, a series of urchin-like Ce(HCOO)3 nanoclusters were synthesized via a facile and scalable microwave-assisted method by varying the irradiation time, and the structure-property relationship was investigated. The optimization of the reaction time was performed based on structural characterizations and electrochemical performances, and the Ce(HCOO)3-210 s sample shows a specific capacitance as high as 132 F g-1 at a current density of 1 A g-1. This is due to the optimal mesoporous hierarchical structure and crystallinity that are beneficial to its conductivity, offering abundant Ce3+/Ce4+ active sites and facilitating the transportation of electrolyte ions. Moreover, an asymmetric supercapacitor based on Ce(HCOO)3//AC was fabricated, which delivers a maximum energy density of 14.78 Wh kg-1 and a considerably high power density of 15,168 W kg-1. After 10,000 continuous charge-discharge cycles at 3 A g-1, the ASC device retains 81.3% of its initial specific capacitance. The excellent comprehensive electrochemical performance of this urchin-like Ce(HCOO)3 offers significant promise for practical supercapacitor applications.

Application of 3D hierarchical porous NiCo-spinel nanosheet array for enhancement of synergistic activation of peroxymonosulfate: Degradation, Intermediates, mechanism and degradation pathway of tetracycline

The rational design of the morphology and structure of bimetallic-based heterogeneous Fenton-like catalyst derived from metal-organic-frameworks (MOFs) for peroxymonosulfate (PMS) activation via a non-radical pathway is attractive but challenging. Herein, a spinel-type 3D hierarchical porous NiCo2O4 nanosheet array for the activation of PMS is rationally designed by surfactant-assisted interfacial engineering. The experimental results showed that the NiCo2O4/PMS system demonstrated remarkable oxidative degradation of tetracycline (TC) through 1O2 attack and electron transfer process. In literature, it was thought that the PMS activation process in above system is dominated by radical pathway. In this work, we employ surfactant modified-nanostructure engineering to design hierarchical mesoporous nanosheet array structures and combined them with intrinsic bimetallic synergy to enhance catalytic activity, and interestingly the strategy transformed the PMS activation pathway into a nonradical (1O2 and electron transfer)-dominated process. This is benefit from the favorable morphological and electronic structure of the designed catalysts to facilitate mass transfer and electron transfer processes. The system also possessed a broad spectrum for degrading other typical contaminants, and was effective in tolerating actual water matrix and pH changes, as well as resisting interference from anions and organic matter. Furthermore, the robust stability of the structure and catalytic activity make it promising for practical water treatment. It can be expected that this proposal will provide insights for the delicate structural design and the understanding of its PMS activation mechanism of bimetallic-based Fenton-like catalysts, as well as for the efficient degradation of emerging organic pollutants.

Dual surfactants-assisted adsorption of lithium ions in liquid lithium resources on a superhydrophilic spinel-type H4Ti5O12 ion sieve

The industrial application scope of spinel-type titanium oxide ion sieves is limited by its low adsorption efficiency and regeneration performance. In this study, H4Ti5O12 (HTO-IV), a superhydrophilic spinel-type lithium ion sieve, was synthesized for the first time with the dual surfactants of CTAB and F127 to modulate the surface morphology and surface wettability of the raw material. The prepared HTO-IV lithium ion sieve was composed of ultrathin nanosheets assembled into microspheres and showed excellent surface hydrophilicity and an open hierarchical mesoporous structure, which allowed rapid ion exchange between Li+ and H+. Li+ adsorption rate exceeded 85 % within 30 min and its maximum theoretical adsorption capacity was 57.90 mg/g. The adsorption process of Li+ on HTO-IV followed a pseudo-second-order kinetic model and Langmuir adsorption isotherm model. HTO-IV also exhibited good adsorption selectivity towards Li+ in the presence of coexisting ions. Furthermore, the lithium adsorption ratio of the HTO-IV ion sieve remained at around 97 % even after five adsorption–desorption cycles, demonstrating excellent adsorption capacity and cycling stability. The study highlights the relationship between surface hydrophilicity and adsorption performance of the adsorbent.

A promising palm leaves waste-derived biochar for efficient removal of tetracycline from wastewater

Tetracycline (TC) is among the most commonly used antibiotics on the market today. As a result, huge amounts of TC-contaminated water enter the aquatic environment. This drug is considered an emerging pollutant and can cause acute problems for flora and fauna. Therefore, an efficient adsorbent is needed to remove TC from water bodies. Plant-based biochar can be a promising way to remove TC from water. In this work, a biochar (PLB) is made from dead palm leaves (PL), as a novel, eco-friendly, and effective adsorbent. The surface morphology and structural properties of the prepared adsorbent were confirmed by different characterization techniques. The results confirmed that the PLB has a higher surface area and more mesoporous hierarchical structure compared to raw PL. TC Adsorption experiments were carried out under different environmental conditions including contact time, solution pH, initial concentration of TC, adsorbent dose, and temperature. The adsorption kinetics data corroborated a pseudo-second order (PSO) model while the monolayer uptake capacity was found to be 13.71 mg/g and 6.52 mg/g for PLB and PL, respectively. The adsorption process was spontaneous and endothermic. The adsorbent exhibited regeneration capabilities for at least three consecutive cycles. The H-bonding, π-π interaction, electrostatic interaction, and pore-filling played a dominant role in TC adsorption. According to the study's findings, inexpensive biochar adsorbent is effective at removing TC and may also be used to potentially remove other toxins from vast amounts of wastewater samples.

Constructing MOF-derived V2O5 as advanced cathodes for aqueous zinc ion batteries

Aqueous zinc-ion batteries (AZIBs) have become incremental attention due to its low cost, material abundance and environmental friendliness. Unfortunately, the crucial challenge is to develop cathodes with satisfactory superior Zn2+ storage. Here, a hierarchical porous V2O5 nano-bulk (p-V2O5) was synthesized derived from vanadium-based metal-organic framework via carbonization as cathode for AZIBs. The hierarchical mesoporous structure and elevated specific surface area are conducive to promote ion/electron transport. The prepared cathode delivers a high specific capacity of 115 mAh g−1 even at 3 A g−1. We also demonstrate that the Zn2+ storage mechanism is a reversible Zn2+ insertion/extraction in the open-structured Zn3(OH)2V2O7·2H2O and ZnyV2O5·nH2O in the subsequent cycling. The distinguished Zn2+ storage performance makes p-V2O5 a potential cathode for the next generation AZIBs.

Long-Term Stability of Seawater Acidification and Its Effect on the Formation of Mg(OH)2 Films with a Hierarchical Porous Structure in Bipolar Membrane-Based Direct Seawater Electrolysis

This is the first report discussing the long-term stability (1000 h) of direct seawater electrolysis (DSWE) in relation to seawater acidification and inorganic precipitation. Unlike general DSWE, in which inorganic precipitates are formed at the cathode surface due to a local pH increase caused by the hydrogen evolution reaction (HER), bipolar membrane-based DSWE acidified natural seawater to pH 3, suppressing the formation of inorganic precipitates and inducing a positive shift in the equilibrium potential for the HER. Because the acidified seawater became alkaline after 300 h, periodic seawater replacement was suggested as a method of maintaining seawater acidification for 1000 h, during which a Mg(OH)2 film with a thickness of 1 mm or more was formed at the cathode surface. Using Brunauer–Emmett–Teller (BET) analysis, water vapor sorption, and electrochemical impedance analysis, it was confirmed that the Mg(OH)2 film has a hierarchical mesoporous structure and high affinity for water, which maintained mass transport. The unique properties of the Mg(OH)2 film under seawater acidification contributed to a lower rate of increase in the cathodic potential than that under seawater alkalization, where very thin inorganic deposits were formed.

Study on energy storage characteristics of self-assembly Zn-Co-oxide microspheres composite

Rambutan-like ZnCo2O4 microsphere was successfully synthesized on foam nickel (NF) by facile low-temperature hydrothermal method. The unique structure is composed of nanorods by self-assembly, eventually resulting in a porous hierarchical structure consisting of microspheres in the center and spiny nanorods growing outward. The specific capacity of ZnCo2O4/NF remains at 877.91 mAh g−1 after 400 cycles with a current density of 0.2 A g−1 and 723.33 mAh g−1 at a current density of 1 A g−1 in the rating performance. Its excellent cycling and rating performance is attributed to its unique hierarchical mesoporous structure and high carrier transport efficiency. In addition, the hierarchical structure improves the pseudo-capacitance effect at the electrode interface, enhancing the additional reversible capacity and charge/discharge capability.

Design of a super-hydrophilic/super-oleophobic g-C3N4/Ti(OH)4/PFOA nanocomposite coated mesh as a smart nanofilter with robust anti-fouling properties for separation of oil and water emulsions

The design and development of efficient approaches for water–oil separation have had widespread interest. This study aimed to synthesize nanocomposites based on Ti(OH)4 and g-C3N4 nanosheets (CN-NS) to show experimentally that the inclusion of Ti(OH)4 nanoparticles of 9.2 nm size into CN-NS leads to an improved oil-water separation efficiency and anti-fouling performance. So, a novel, reusable, and recyclable super-hydrophilic/underwater super-oleophobic CN-NS/Ti(OH)4 nanocomposite-coated stainless steel mesh was developed to separate oil-in-water emulsions. Super-wettability was obtained in the CN-NS/Ti(OH)4 nanocomposite with WCA = 0° and UOCA = 154°, respectively, showing significant super-hydrophilicity and underwater super-oleophobicity. Surface hydrophilicity increased after anchoring Ti(OH)4 on the CN-NS surface, resulting from oxygen-containing functional groups and consequently making defects on the mesh surface. Enhanced underwater oleophobicity of nanocomposite coated mesh is attributed to its higher surface roughness, which is a result of its micro-nano meter and mesoporous hierarchical structure. Moreover, the self-cleaning property of the as-prepared mesh was demonstrated by visible light irradiation on the contaminated mesh. In addition, perfluorooctanoic acid (PFOA) reduced energy in CN-NS/Ti(OH)4/PFOA mesh, resulting in a super-hydrophilic/super-oleophobic mesh. The CN-NS/Ti(OH)4/PFOA nanocomposite-coated filter was observed to separate water from a 1 wt% water-in-oil emulsion at 0.2 bar pressure with a filtration flux of 317.2 L m−2 h−1 and 95% separation efficiency.

Porphyrin-based conjugated microporous adsorbent material for the efficient remediation of hexavalent chromium from the aquatic environment.

The encapsulation and eradication of anions from water have received a lot of scrutinize and are extremely important for virtuous production and environmental treatment. To prepare extremely efficient adsorbents, a highly functionalized and conjugated microporous porphyrin-based adsorbent material (Co-4MPP) was synthesized using the Alder Longo method. Co-4MPP featured a hierarchical microporous and mesoporous layered structure containing nitrogen and oxygen-based functional groups with a specific surface area of 685.209 m2/g and a pore volume of 0.495 cm3/g. Co-4MPP demonstrated a greater Cr (VI) adsorption empathy than the pristine porphyrin-based material did. The effects of various parameters such as pH, dose, time, and temperature were explored on the Cr (VI) adsorption by Co-4MPP. The pseudo-second-order model and the Cr (VI) adsorption kinetics were in agreement (R2 = 0.999). The Langmuir isotherm model matched the Cr (VI) adsorption isotherm, demonstrating the optimum Cr (VI) adsorption capacities: 291.09, 307.42, and 339.17 mg/g at 298K, 312K, and 320K, correspondingly, with remediation effectiveness of 96.88%. The model evaluation further revealed that Cr (VI) adsorption mechanism on Co-4MPP was endothermic, spontaneous, and entropy-rising. The detailed discussion of the adsorption mechanism suggested that it could be a reduction, chelation, and electrostatic interaction, in which the protonated nitrogen and oxygen-containing functional groups on the porphyrin ring interacted with Cr (VI) anions to form a stable complex, thus remediating Cr (VI) anions efficiently. Moreover, Co-4MPP demonstrated strong reusability, maintaining 70% of its Cr (VI) elimination rate after four consecutive adsorptions.

Evaluation of pH-sensitive nanocontainers composed of hierarchical ZnO mesoporous structures loaded with the Mimosa tenuiflora extract for applications in a saline solution

Evaluation of pH-sensitive nanocontainers composed of hierarchical ZnO mesoporous structures loaded with the Mimosa tenuiflora extract for applications in a saline solution

Synthesis and characteristics of carbon-SnO2 composite aerogel via two-step self-assembly approach

Aerogels with unique hierarchical structure have attracted more and more attention in recent years. Especially, semiconductor aerogel, as one representative, is emerging owing to their controllable binding energy, bandgap, morphology, etc. In this work, a two-step self-assembly strategy of liquid phase was adopted to create carbon-mixed SnO2 gel, where SnO2 gel was self-assembled in a molecular route and then transformed into carbon-SnO2 gel at the second stage induced by interaction with the carbon resource (glucose) under hydrothermal condition. In this process, SnO2 colloids, rather than tin ions, could not only accelerate the carbonization of glucose molecules, but also help to build the cross-linking network of non-covalent bonding. Subsequently, freeze-drying was utilized to discharge the liquid from carbon-SnO2 gel to form aerogels. In addition, the evolution of hybrid carbon-mixed SnO2 aerogels during calcining at different temperature was also discussed. As carbon-containing structure blocked inside pores gradually grew into flaky carbon or was thermolyzed after calcination, previous microporous and mesoporous hierarchical structure was recovered and then SnO2-based composite aerogels were generated, even were reduced as Sn-based composite aerogels at 850 °C in nitrogen. As a result, hybrid Sn-based composite aerogels exhibited a higher BET surface area and good electrical conductivity (3 S/cm).

Hierarchical mesoporous binary nickel cobalt selenides nanospheres for enhanced sodium-ion storage

Owing to high theoretical specific capacity, transition metal selenides as prospective anode materials for sodium-ion batteries (SIBs) have caused extraordinary concern. However, the poor electrochemical property caused by the large volume changes and relatively low electrical conductivity limits their practical application. Herein, uniform Ni0.33Co0.67Se2 nanosphere with hierarchical mesoporous structure was synthesized successfully through a feasible solvothermal selenization strategy. The unique hierarchical mesoporous nanostructure and enhanced electrical conductivity from binary metal selenide combination result in excellent Na+ storage performance. The as-prepared Ni0.33Co0.67Se2 anode material delivers ultra-long cycling life (301.9 mAh g−1 after 1300 cycles at 1.0 A g−1 with low per-cycle capacity decay ∼ 0.062 mAh g−1) and excellent rate capability (314.5 mAh g−1 at 8.0 A g−1) for SIBs. Besides, the quantitative kinetic analysis results indicate the superior Na+ storage performance of the Ni0.33Co0.67Se2 electrode might be imputed to the dominant pseudocapacitive behavior. These results prove the binary nickel cobalt selenides have great potential as anode materials for SIBs.

In situ synthesis of low-valence MnO/Mn3O4 catalyst via carbon-acid hydrothermal strategy for NO removal

A rational design of high dispersion MnO/Mn 3 O 4 catalysts based on carbon-acid hydrothermal strategy was proposed for selective catalytic reduction of NO at low temperature. The ultra-high denitration rate can be attributed to the abundant Lewis acid sites and reactive oxygen species, and the reaction followed Langmuir-Hinshelwood reaction route. • High dispersed MnO/Mn 3 O 4 catalyst was prepared by carbon-acid hydrothermal method. • Catalyst achieved exceeding 98 % NO removal in the temperature window of 80–200 °C. • Rich Lewis acid sites and reactive oxygen species contributed to high SCR activity. • In-situ DRIFTS proved the SCR reaction process followed Langmuir-Hinshelwood route. A rational design of high dispersion MnO/Mn 3 O 4 catalysts based on carbon-acid hydrothermal strategy was proposed for selective catalytic reduction of NO at low temperature. The reaction mechanisms of low valence manganese coordination and catalytic path were revealed through active site analysis and in-situ DRIFTS characterization. The results showed that reasonable low valence manganese nanofibers cooperated to derive hierarchical mesoporous structure and abundant surface active oxygen. The chemisorbed oxygen specie cooperated with Lewis acid sites accelerated the production of NO 2 in the catalytic process and realized high-efficiency NO removal at ultra-low temperature. Such a facile preparation method of low valence manganese nanofibers structure widens the way for NH 3 -SCR of NO in industrial practice.

Facile preparation of hierarchical mesoporous silica microspheres with tunable porous structure and particle sizes

This work reports that, by supplementing classical ternary template system (TEOS/P123/HCl(aq.)) with poly (vinyl alcohol) (PVA) as additive, hierarchical mesoporous silica (HMS) microspheres can be prepared with tunable particle sizes and porous structures based on the partitioned cooperative self-assembly (PCSA) process. The particle sizes and hierarchical mesoporous (HM) structures of HMS microspheres are found to dependent on the experimental parameters, such as PVA dosages, synthesis/hydrothermal treatment temperatures and partitioning conditions, etc. The BET surface area, pore volume and particle size of typical HMS microsphere sample of 6-4h-4@40P15 reach 792 m2g-1, 1.74 cm3g-1 and 3.51 μm, respectively. The 1st and 2nd mode mesopore sizes are 10.5 nm and 20.5 nm, respectively. Large synthesis domains for HMS microspheres defined by different synthesis parameters were also obtained, enabling their easy and controllable preparation. The scaled-up preparation of HMS microspheres up to five times was also demonstrated with comparable particle morphology and sizes. PVA was newly found to play multiple roles in the preparation of HMS microspheres in (1) improving the dispersibility and spherical morphology, (2) shaping the HM structures and (3) broadening the synthesis domain. The facile and controllable HMS microspheres might further promote their application in different areas.

Edge-Site Engineering of Defective Fe-N4 Nanozymes with Boosted Catalase-Like Performance for Retinal Vasculopathies.

Extensive efforts are devoted to refining metal sites for optimizing the catalytic performance of single-atom nanozymes (SANzymes), while the contribution of the defect environment of neighboring metal sites lacks attention. Herein, an iron-based SANzyme (Fe-SANzyme) is rationally designed by edge-site engineering, which intensively exposes edge-hosted defective Fe-N4 atomic sites anchored in hierarchical mesoporous structures. The Fe-SANzyme exhibits excellent catalase-like activity capable of efficiently catalyzing the decomposition of H2 O2 into O2 and H2 O, with a catalytic kinetic KM value superior to that of natural catalase and reported nanozymes. The mechanistic studies depict that the defects introduce notable charge transfer from the Fe atom to the carbon matrix, making the central Fe more activated to strengthen the interaction with H2 O2 and weaken the OO bond. By performing catalase-like catalysis, the Fe-SANzyme significantly scavenges reactive oxygen species (ROS) and alleviates oxidative stress, thus eliminating the pathological angiogenesis in animal models of retinal vasculopathies without affecting the repair of normal vessels. This work provides a new way to refine SANzymes by engineering the defect environment and geometric structure around metal sites, and demonstrates the potential therapeutic effects of the nanozyme on retinal vasculopathies.

TiO2-immobilized porous geopolymer composite membrane for removal of antibiotics in hospital wastewater

This experimental research proposes an environment-friendly and low-cost porous geopolymer composite membrane (PGCM) to treat antibiotics in hospital wastewater. The proposed PGCM consisted of two layers: a porous support layer and a dense coating layer. The dense coating layer was synthesized by incorporating variable TiO2 content (0, 2, 6, and 10 wt%) into the geopolymer matrix. The dense coating layer was of hierarchical mesoporous structure with 700 μm in thickness and adhered to the porous support layer. The average pore size, total pore volume, and open porosity of the dense coating layer decreased with an increase in TiO2, resulting in reduced water permeability. The PGCM was applied to remove six target antibiotics including amoxicillin, ciprofloxacin, norfloxacin, sulfamethoxazole, tetracycline, and trimethoprim in real hospital wastewater. By comparison, the PGCM with 10 wt% TiO2 achieved the highest antibiotic removal efficiencies, with the adsorption and combined adsorption/photodegradation removal efficiencies for the target antibiotics of 38–75% and 74–86%, respectively. The novelty of this research lies in the use of a tailor-made porous geopolymer composite membrane incorporated with TiO2 photooxidation as a single-step treatment of recalcitrant antibiotics contained in hospital wastewater.

Noble-Metal-Based Hollow Mesoporous Nanoparticles: Synthesis Strategies and Applications.

As second-generation mesoporous materials, mesoporous noble metals (NMs) are of significant interest for their wide applications in catalysis, sensing, bioimaging, and biotherapy owing to their structural and metallic features. The introduction of interior hollow cavity into NM-based mesoporous nanoparticles (MNs), which subtly integrate hierarchical hollow and mesoporous structure into one nanoparticle, produces a new type of hollow MNs (HMNs). Benefiting from their higher active surface, better electron/mass transfer, optimum electronic structure, and nanoconfinement space, NM-based HMNs exhibit their high efficiency in enhancing catalytic activity and stability and tuning catalytic selectivity. In this review, recent progress in the design, synthesis, and catalytic applications of NM-based HMNs is summarized, including the findings of the groups. Five main strategies for synthesizing NM-based HMNs, namely silica-assisted surfactant-templated nucleation, surfactant-templated sequential nucleation, soft "dual"-template, Kirkendall effect in synergistic template, and galvanic-replacement-assisted surfactant template, are described in detail. In addition, the applications in ethanol oxidation electrocatalysis and hydrogenation reactions are discussed to highlight the high activity, enhanced stability, and optimal selectivity of NM-based HMNs in (electro)catalysis. Finally, the further outlook that may lead the directions of synthesis and applications of NM-based HMNs is prospected.