In this article, a simple and mild preparation of secondary pores are reported, for the first time, with uniform and tunable sizes (in a wide range of 0.9–4.8 nm) in the walls highly connecting the primary mesochannels in 3D mesopore networks. The uniform secondary pores are obtained by using ordered 2D hexagonal mesoporous anatase TiO₂–SiO₂ nanocomposites as precursors, NaOH as an etchant via an “extracting SiO₂” approach. The strategy here adopts diluted NaOH solution, appropriate extraction temperature, and solid/liquid ratio. The photocatalytic degradation rates of Rhodamine B (0.347 min^–1), Acid Red 1 (0.0487 min^–1), microcystin–LR (1.66 min^–1) on the representative resultant nanocomposite are very high, which are 4.63, 11.7, 1.84 times that of the precursor without secondary mesopores; even up to 18.9, 8.21, 4.66 times that of P25, respectively. These results clearly demonstrate that the secondary mesopores play an overwhelming role to the increments of activities. The mesoporous anatase–silica nanocomposites with secondary mesopores present unprecedented-high degradation activities to various organic pollutants in the mesoporous metal-oxides-based materials reported up to now and are considerably stable and reusable. It is believed that the fundamentals in this study will provide new insights for rational design and preparation of 3D highly interconnected mesoporous metal-oxides-based materials with super-high performances.

Transition metal oxides are regarded as promising anode materials for lithium-ion batteries because of their high theoretical capacities compared with commercial graphite. Unfortunately, the implementation of such novel anodes is hampered by their large volume changes during the Li⁺ insertion and extraction process and their low electric conductivities. Herein, we report a specifically designed anode architecture to overcome such problems, that is, mesoporous peapod-like Co₃O₄@carbon nanotube arrays, which are constructed through a controllable nanocasting process. Co₃O₄ nanoparticles are confined exclusively in the intratubular pores of the nanotube arrays. The pores between the nanotubes are open, and thus render the Co₃O₄ nanoparticles accessible for effective electrolyte diffusion. Moreover, the carbon nanotubes act as a conductive network. As a result, the peapod-like Co₃O₄@carbon nanotube electrode shows a high specific capacity, excellent rate capacity, and very good cycling performance.

Transition metal oxides are regarded as promising anode materials for lithium-ion batteries because of their high theoretical capacities compared with commercial graphite. Unfortunately, the implementation of such novel anodes is hampered by their large volume changes during the Li⁺ insertion and extraction process and their low electric conductivities. Herein, we report a specifically designed anode architecture to overcome such problems, that is, mesoporous peapod-like Co₃O₄@carbon nanotube arrays, which are constructed through a controllable nanocasting process. Co₃O₄ nanoparticles are confined exclusively in the intratubular pores of the nanotube arrays. The pores between the nanotubes are open, and thus render the Co₃O₄ nanoparticles accessible for effective electrolyte diffusion. Moreover, the carbon nanotubes act as a conductive network. As a result, the peapod-like Co₃O₄@carbon nanotube electrode shows a high specific capacity, excellent rate capacity, and very good cycling performance.

The design and fabrication of core–shell and yolk–shell nanostructures with surface plasmon resonance (SPR)-active center protected by permeable mesoporous channels can raise the new vitality into the catalysis and biological applications. Hybrid plasmonic-mesoporous silica nanocarriers consisting of Ag and Au–Ag alloy nanoparticles are fabricated through spatially confined galvanic replacement approach. The plasmonic absorption peaks can be finely controlled to the near-infrared (NIR) region (500–790 nm) that is beneficial for tissue transmittance. The mesoporous silica shell facilitates also protection of Au–Ag cores and affords the channels between the exterior and interior capsule environments, thereby endowing the multiple applications. In the present work, it is successfully demonstrated that mesoporous silica-coated Au–Ag alloy core–shell and yolk–shell nanocarriers can serve as good substrates for surface-enhanced Raman scattering (SERS) detection. The SERS signal intensities of nanocarriers are highly dependent on the SPR peaks and the contents of gold. Simultaneously, the synthesized Au-Ag@mSiO₂ nanocarriers with SPR peak at ≈790 nm can be applied in NIR-sensitive SERS detection and photothermal therapy.

Monodispersed mesoporous phenolic polymer nanospheres with uniform diameters were prepared and used as the core for the further growth of core–shell mesoporous nanorattles. The hierarchical mesoporous nanospheres have a uniform diameter of 200 nm and dual-ordered mesopores of 3.1 and 5.8 nm. The hierarchical mesostructure and amphiphilicity of the hydrophobic carbon cores and hydrophilic silica shells lead to distinct benefits in multidrug combination therapy with cisplatin and paclitaxel for the treatment of human ovarian cancer, even drug-resistant strains.

Monodispersed mesoporous phenolic polymer nanospheres with uniform diameters were prepared and used as the core for the further growth of core–shell mesoporous nanorattles. The hierarchical mesoporous nanospheres have a uniform diameter of 200 nm and dual-ordered mesopores of 3.1 and 5.8 nm. The hierarchical mesostructure and amphiphilicity of the hydrophobic carbon cores and hydrophilic silica shells lead to distinct benefits in multidrug combination therapy with cisplatin and paclitaxel for the treatment of human ovarian cancer, even drug-resistant strains.

A facile approach for the synthesis of ultralight iron oxide hierarchical structures with tailorable macro- and mesoporosity is reported. This method entails the growth of porous Prussian blue (PB) single crystals on the surface of a polyurethane sponge, followed by in situ thermal conversion of PB crystals into three-dimensional mesoporous iron oxide (3DMI) architectures. Compared to previously reported ultralight materials, the 3DMI architectures possess hierarchical macro- and mesoporous frameworks with multiple advantageous features, including high surface area (ca. 117 m² g⁻¹) and ultralow density (6–11 mg cm⁻³). Furthermore, they can be synthesized on a kilogram scale. More importantly, these 3DMI structures exhibit superparamagnetism and tunable hydrophilicity/hydrophobicity, thus allowing for efficient multiphase interfacial adsorption and fast multiphase catalysis.

Core–shell nanoparticles (CSNs) have attracted considerable attention because of their promising applications in a wide range of fields. Recently, substantial efforts have been focused on the development of facile and versatile methods for preparing CSNs with mesoporous SiO₂ or TiO₂ shells because of their fascinating properties, such as high surface area, large pore channels and high pore volume. This Research News reviews the recent progress in facile, versatile and reproducible approaches which are simply extended from the well-known Stöber method to construct mesoporous SiO₂ and TiO₂ shells for uniform multifunctional core–shell nanostructures. Several strategies, including the surfactant-templating process, the long-chain organosilane-assisted approach, the phase transfer assisted surfactant-templating process, and the kinetics-controlled coating approach, are discussed. In addition, new trends in this field for the creation of multifunctional CSNs and novel nanostructures are highlighted.

A controllable one-pot method to synthesize N-doped ordered mesoporous carbons (NMC) with a high N content by using dicyandiamide as a nitrogen source via an evaporation-induced self-assembly process is reported. In this synthesis, resol molecules can bridge the Pluronic F127 template and dicyandiamide via hydrogen bonding and electrostatic interactions. During thermosetting at 100 °C for formation of rigid phenolic resin and subsequent pyrolysis at 600 °C for carbonization, dicyandiamide provides closed N species while resol can form a stable framework, thus ensuring the successful synthesis of ordered N-doped mesoporous carbon. The obtained N-doped ordered mesoporous carbons possess tunable mesostructures (p6m and Imm symmetry) and pore size (3.1–17.6 nm), high surface area (494–586 m² g⁻¹), and high N content (up to 13.1 wt%). Ascribed to the unique feature of large surface area and high N contents, NMC materials show high CO₂ capture of 2.8–3.2 mmol g⁻¹ at 298 K and 1.0 bar, and exhibit good performance as the supercapacitor electrode with specific capacitances of 262 F g⁻¹ (in 1 M H₂SO₄) and 227 F g⁻¹ (in 6 M KOH) at a current density of 0.2 A g⁻¹.

A fascinating core–shell-structured graphitic carbon material composed of ordered microporous core and uniform mesoporous shell is fabricated for the first time through a site-specific chemical vapor deposition process by using a nanozeolite@mesostructured silica composite molecular sieve as the template. The mesostructure-directing agent cetyltrimethylammonium bromide in the shell of the template can be either burned off or carbonized so that it is successfully utilized as a pore switch to turn the shell of the template “on” or “off” to allow selective carbon deposition. The preferred carbon deposition process can be performed only in the inner microporous zeolite cores or just within the outer mesoporous shells, resulting in a zeolite-like ordered microporous carbon or a hollow mesoporous carbon. Full carbon deposition in the template leads to the new core–shell-structured microporous@mesoporous carbon with a nanographene-constructed framework for fast electron transport, a microporous nanocore with large surface area for high-capacity storage of lithium ions, a mesoporous shell with highly opened mesopores as a transport layer for lithium ions and electron channels to access inner cores. The ordered micropores are protected by the mesoporous shell, avoiding pore blockage as the formation of solid electrolyte interphase layers. Such a unique core–shell-structured microporous@mesoporous carbon material represents a newly established lithium ion storage model, demonstrating high reversible energy storage, excellent rate capability, and long cyclic stability.

A series of core–shell-structured composite molecular sieves comprising zeolite single crystals (i.e., ZSM-5) as a core and ordered mesoporous silica as a shell were synthesized by means of a surfactant-directed sol–gel process in basic medium by using cetyltrimethylammonium bromide (CTAB) as a template and tetraethylorthosilicate (TEOS) as silica precursor. Through this coating method, uniform mesoporous silica shells closely grow around the anisotropic zeolite single crystals, the shell thickness of which can easily be tuned in the range of 15–100 nm by changing the ratio of TEOS/zeolite. The obtained composite molecular sieves have compact meso-/micropore junctions that form a hierarchical pore structure from ordered mesopore channels (2.4–3.0 nm in diameter) to zeolite micropores (≈0.51 nm). The short-time kinetic diffusion efficiency of benzene molecules within pristine ZSM-5 (≈7.88×10⁻¹⁹ m² s⁻¹) is almost retainable after covering with 75 nm-thick mesoporous silica shells (≈7.25×10⁻¹⁹ m² s⁻¹), which reflects the greatly opened junctions between closely connected mesopores (shell) and micropores (core). The core–shell composite shows greatly enhanced adsorption capacity (≈1.35 mmol g⁻¹) for large molecules such as 1,3,5-triisopropylbenzene relative to that of pristine ZSM-5 (≈0.4 mmol g⁻¹) owing to the mesoporous silica shells. When Al species are introduced during the coating process, the core–shell composite molecular sieves demonstrate a graded acidity distribution from weak acidity of mesopores (predominant Lewis acid sites) to accessible strong acidity of zeolite cores (Lewis and Brønsted acid sites). The probe catalytic cracking reaction of n-dodecane shows the superiority of the unique core–shell structure over pristine ZSM-5. Insight into the core–shell composite structure with hierarchical pore and graded acidity distribution show great potential for petroleum catalytic processes.

Carbon materials have attracted intense interests as electrode materials for electrochemical capacitors, because of their high surface area, electrical conductivity, chemical stability and low cost. Activated carbons produced by different activation processes from various precursors are the most widely used electrodes. Recently, with the rapid growth of nanotechnology, nanostructured electrode materials, such as carbon nanotubes and template-synthesized porous carbons have been developed. Their unique electrical properties and well controlled pore sizes and structures facilitate fast ion and electron transportation. In order to further improve the power and energy densities of the capacitors, carbon-based composites combining electrical double layer capacitors (EDLC)-capacitance and pseudo-capacitance have been explored. They show not only enhanced capacitance, but as well good cyclability. In this review, recent progresses on carbon-based electrode materials are summarized, including activated carbons, carbon nanotubes, and template-synthesized porous carbons, in particular mesoporous carbons. Their advantages and disadvantages as electrochemical capacitors are discussed. At the end of this review, the future trends of electrochemical capacitors with high energy and power are proposed.

A new three-dimensional microporous metal–organic framework (MOF) Zn(BDC-OH)(DABCO)_0.5·(DMF)₂(H₂O) (UTSA-25; H₂BDC-OH = 2-hydroxybenzenedicarboxylic acid, DABCO = 1,4-diazabicyclo[2.2.2]octane) with functional–OH groups on the pore surfaces was solvothermally synthesized and structurally characterized. UTSA-25 features a three-dimensional structure with 3D intercrossed channels of about 7.5 × 7.5, 3.2 × 4.7, and 3.2 × 4.7 Ų, respectively. The small pores and the functional –OH groups on the pore surfaces within the activated UTSA-25a have enabled their strong interactions with CO₂ of adsorption enthalpy of 22.5 kJ mol^–1, which is higher than that of 17.5 kJ mol^–1 in the original MOF Zn(BDC)(DABCO)_0.5 without the functionalized –OH groups. Accordingly, CO₂/CH₄ separation selectivities in UTSA-25a of 17.2 and 12.5 at 273 and 296 K, respectively, are much higher than those of 4.4 and 3.7 in Zn(BDC)(DABCO)_0.5, thus highlighting UTSA-25a as a very promising porous material for industrially important CO₂/CH₄ separation.

Ordered mesoporous carbon C-FDU-18s with tunable pore sizes of 12−33 nm and pore wall thicknesses of 5−11 nm were synthesized by using poly(ethylene oxide)-block-poly(styrene) (PEO-b-PS) diblock copolymers with various PS chain lengths as templates and through the evaporation induced self-assembly process. The obtained C-FDU-18 carbons possess face-centered cubic mesostructure with Fm3m symmetry, large cell parameters varying from 32 to 54 nm, high Brunauer–Emmett–Teller surface area up to 1000 m² g⁻¹ and large pore volume of about 0.7 cm³ g⁻¹. By oxidative treatment of HNO₃ and H₂O₂ mixed solution, numerous hydrophilic groups were created in the mesopore channels without destroying the ordered mesostructure of the C-FDU-18. Through the in situ reduction of Ag⁺, Ag nanoparticles (9.7 nm) were successfully introduced into the large mesopores, resulting in functional mesoporous carbons Ag–C-FDU-18 with stably trapped Ag nanoparticles. Similarly, by reduction of Fe³⁺ ions in the large mesopores, superparamagnetic Fe–C-FDU-18 with incorporated magnetic nanoparticles (6.2 nm) and fast magnetic response was synthesized. These functional large-pore mesoporous carbons have high potential for application in various fields such as catalysis, chemical sensing, and magnetic separation and enrichment.

A new two-dimensional microporous metal–organic framework Cu(BDC-OH)(H₂O)·0.5DEF [abbreviation: Cu(BDC-OH); H₂BDC-OH = 2-hydroxybenzene-1,4-dicarboxylic acid; DEF = diethylformamide] with functional OH groups on the pore surfaces was solvothermally synthesized and structurally characterized. The activated Cu(BDC-OH) exhibits a moderate Langmuir surface of 584 m² g^–1, a pore volume of 0.214 cm³ g^–1, and C₂H₂/CH₄ and CO₂/CH₄ selectivity of 6.7 and 9.3, respectively, at 296 K, thereby highlighting the promise for its application in gas separation.

Lead tungstate (PbWO₄) crystals with unique hierarchical morphologies have been successfully synthesized in the presence of a triblock copolymer poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) (EO₇₀-PO₂₀-EO₇₀, P₁₂₃) under mild hydrothermal conditions. When reaction temperature is changed from 140 to 180 and 220 °C, the as-obtained PbWO₄ samples can vary from flat tubular to rod-shaped arrays and complex slabs with porous film texture on their surface. Meanwhile, by using polyvinylpyrolidone (PVP), cetyltrimethylammonium bromide (CTAB), andhydroxycellulose with distinct functional groups as structure-directing agents, PbWO₄ samples such as polyhedrons and rods with porous groove texture, as well as tube-shaped aggregate bundles, can be obtained. The optical properties of the as-made PbWO₄ samples with various morphologies were examined by photoluminescence (PL) and Raman spectroscopy. Results show that PL of the rod-like arrays and microtube structures is redshifted relative to that of the complex slab sample. In general, the present synthesis route may be extended to prepare other inorganic nanomaterials with special functions.

High-quality rare-earth fluorides, α-NaMF₄ (M=Dy, Ho, Er, Tm, Y, Yb, and Lu) nanocrystals and β-NaMF₄ (M=Pr, Nd, Sm, Eu, Gd, Tb, Dy, Ho, Er, Tm, Y, Yb, and Lu) nanoarrays, have been synthesized by using oleic acid as a stabilizing agent through a facile hydrothermal method at 130–230 °C. The phase, shape, and size of the products are varied by careful control of synthetic conditions, including hydrothermal temperature and time, and the amounts of reactants and solvents. Tuning the hydrothermal temperature, time, and the amount of NaOH can cause the transformation from the cubic α-NaMF₄ to hexagonal phase β-NaMF₄. Upon adjustment of the amount of NaOH, NaF, M³⁺, and ethanol, the morphologies for the β-NaMF₄ nanoarrays can range from tube, rod, wire, and zigzagged rod, to flower-patterned disk. Simultaneously, the size of the rare-earth fluoride crystals is variable from 5 nm to several micrometers. A combination of “diffusion-controlled growth” and the “organic–inorganic interface effect” is proposed to understand the formation of the nanocrystals. An ideal “1D growth” of rare-earth fluorides is preferred at high temperatures and high ethanol contents, from which the tube- and rodlike nanoarrays with high aspect ratio are obtained. In contrast, the disklike β-NaMF₄ nanoarrays with low aspect ratios are produced by decreasing the ethanol content or prolonging the reaction time, an effect probably caused by “1D/2D ripening”. Multicolor up-conversion fluorescence is also successfully realized in the Yb³⁺/Er³⁺ (green, red) and Yb³⁺/Tm³⁺ (blue) co-doped α-NaYF₄ nanocrystals and β-NaYF₄ nanoarrays by excitation in the NIR region (980 nm).