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Abstract: Mesoporous carbon can be synthesized with good control of surface area, pore‐size distribution, and porous architecture. Although the relationship between porosity and supercapacitor performance is well known, there are no thorough reports that compare the performance of numerous types of carbon samples side by side. In this manuscript, we describe the performance of 13 porous carbon samples in supercapacitor devices. We suggest that there is a “critical pore size” at which guest molecules can pass through the pores effectively. In this context, the specific surface area (SSA) and pore‐size distribution (PSD) are used to show the point at which the pore size crosses the threshold of critical size. These measurements provide a guide for the development of new kinds of carbon materials for supercapacitor devices. [ABSTRACT FROM AUTHOR]

Abstract: As one of the most promising energy storage devices, the practical application of lithium–sulfur batteries is limited by the low electrical conductivity of sulfur and the notable “shuttle effects” of sulfur‐based electrodes. In this work, we describe a hierarchically porous N‐doped zeolitic imidazolate framework‐8 (ZIF‐8)‐derived carbon nanosphere (N‐ZDC) with an outer shell and an inner honeycomb‐like interconnected nanosheet network as sulfur host material for high‐performance and long‐term lithium–sulfur batteries. The N‐ZDC serves as multilayered barrier against the dissolution of lithium polysulfides. The porously inner interconnected carbon network of the N‐ZDC facilitates the electron and ion transportation, ensures a high sulfur loading, and accommodates a volume expansion of the sulfur species. As a result, the optimized N‐ZDC4/S electrodes displayed high initial specific capacities of 1343, 1182, and 698 mAh g−1 at 0.5, 1, and 2 C, respectively, and an ultraslow capacity decay of only 0.048 % per cycle at 2 C over 800 cycles. Even with a high sulfur loading of 3.1 mg cm−2, N‐ZDC4/S still delivered a reversible capacity of 956 mAh g−1 and stabilizes at 544 mAh g−1 after 500 cycles at 0.5 C, revealing the great potential of the novel carbon nanospheres for energy storage application. [ABSTRACT FROM AUTHOR]

Abstract: Although two‐dimensional (2D) carbon materials are widely investigated, a well‐defined 2D carbon nanosheet with an ordered mesostructure has rarely been realized. Monolayer‐ordered mesoporous carbon nanosheets (OMCNS) were prepared through confinement assembly of resol and F127 in the interlayer of montmorillonite (MONT). The nanoscale distance of the interlayer space of MONT only allow the assembly of resol and F127 in the same plane, leading to ordered mesopores perpendicular to carbon nanosheets, and favor the formation of sp2 carbon, resulting in a high degree of graphitization. The mesopores on the carbon nanosheets provide efficient ion diffusion, and the high degree of graphitization provides a fast electron‐transport route, enabling OMCNS as excellent electrode materials for electric double layer capacitors. [ABSTRACT FROM AUTHOR]

In this contribution, a facile two‐step hydrothermal protocol to prepare hierarchical uniform hollow mesoporous NiCo2S4 microdumbbells (NCS‐MDs) for advanced supercapacitors is developed. Physicochemical investigations reveal that the as‐obtained NCS‐MDs with mesoporous channels in nanoshells possess high‐content Co(III) and Ni(III) species, large surface area (≈80 m2 g−1)/pore volume (≈0.12 m3 g−1), and high tap density (≈0.8 g cm−3). When evaluated as an attractive pseudocapacitive electrode, the unique NCS‐MDs with mass loading of 7 mg cm−2 exhibit remarkable gravimetric/volumetric specific capacitances of ≈912 F g−1 (≈729 F cm−3) at 3 A g−1, and even ≈767 F g−1 (≈613 F cm−3) at high current density of 10 A g−1. Additionally, capacitive degradations of ≈13% and ≈18% are observed over 5000 continous cycles at current rates of 6 and 10 A g−1, respectively. Furthermore, a high‐energy‐density hybrid device is fabricated by using hollow NCS‐MDs and biomass‐derived activated carbon as positive and negative electrodes, respectively, and delivers striking energy density of ≈35.4 Wh kg−1 at power density of ≈381.2 W kg−1, and excellent electrochemical stability at various rates over 11 000 consecutive cycles. These fascinating features strongly highlight that the as‐resulted hollow mesoporous NCS‐MDs could be highly anticipated as a promising electrode platform for next‐generation hybrid supercapacitors. [ABSTRACT FROM AUTHOR]

Porous carbon with high specific surface area (SSA), a reasonable pore size distribution, and modified surface chemistry is highly desirable for application in energy storage devices. Herein, we report the synthesis of nitrogen-containing mesoporous carbon with high SSA (1390 m2 g−1), a suitable pore size distribution (1.5-8.1 nm), and a nitrogen content of 4.7 wt % through a facile one-step self-assembly process. Owing to its unique physical characteristics and nitrogen doping, this material demonstrates great promise for application in both supercapacitors and encapsulating sulfur as a superior cathode material for lithium-sulfur batteries. When deployed as a supercapacitor electrode, it exhibited a high specific capacitance of 238.4 F g−1 at 1 A g−1 and an excellent rate capability (180 F g−1, 10 A g−1). Furthermore, when an NMC/S electrode was evaluated as the cathode material for lithium-sulfur batteries, it showed a high initial discharge capacity of 1143.6 mA h g−1 at 837.5 mA g−1 and an extraordinary cycling stability with 70.3 % capacity retention after 100 cycles. [ABSTRACT FROM AUTHOR]

In the work, a facile yet efficient self-sacrifice strategy is smartly developed to scalably fabricate hierarchical mesoporous bi-component-active ZnO/ZnFe2O4 (ZZFO) sub-microcubes (SMCs) by calcination of single-resource Prussian blue analogue of Zn3[Fe(CN)6]2 cubes. The hybrid ZZFO SCMs are homogeneously constructed from well-dispersed nanocrstalline ZnO and ZnFe2O4 (ZFO) subunites at the nanoscale. After selectively etching of ZnO nanodomains from the hybrid, porously assembled ZFO SMCs with integrate architecture are obtained accordingly. When evaluated as anodes for LIBs, both hybrid ZZFO and ZFO samples exhibit appealing electrochemical performance. However, the as-synthesized ZZFO SMCs demonstrate even better electrochemical Li-storage performance, including even larger initial discharge capacity and reversible capacity, higher rate behavior and better cycling performance, particularly at high rates, compared with the single ZFO, which should be attributed to its unique microstructure characteristics and striking synergistic effect between the bi-component-active, well-dispersed ZnO and ZFO nanophases. Of great significance, light is shed upon the insights into the correlation between the electrochemical Li-storage property and the structure/component of the hybrid ZZFO SMCs, thus, it is strongly envisioned that the elegant design concept of the hybrid holds great promise for the efficient synthesis of advanced yet low-cost anodes for next-generation rechargeable Li-ion batteries. [ABSTRACT FROM AUTHOR]

In this work, various novel NiO hierarchical nanostructures, including mesoporous nanotubes by nanoparticles self-assembly, nanowire bundles, dandelions, hollow spheres by rods self–assembly, have been fabricated by a simple hydrothermal process and subsequent thermal decomposition at atmosphere. A detailed study of the effect of experimental parameters on the morphology is also presented. Results and analyses demonstrated that oxalic-acid/NaOH molar ratio has an immense function in the subtle morphology control of NiO products. Electrochemical characterization demonstrated that the mesoporous NiO nanotubes were capable of delivering a specific capacitance (SC) of 405 F g−1at the current density of 0.5 A g−1and offered good capacitance retention of ca.91% after 1500 continuous charge-discharge cycles. This soundly indicates that as electrode material, the as-prepared NiO mesoporous nanostructures could meet key requirements in terms of large power density, outstanding rate capability and excellent electrochemical stability. [ABSTRACT FROM AUTHOR]

Heterostructured materials are interesting because they may combine two or more material building blocks that together generate new types of heterointerfaces with unusual properties. Using them to construct large‐scale 3D frameworks further extends their utility in electrochemical applications because it exposes more interfaces and active sites. In this study, electrostatic interactions are used to wrap polyhedra particles of zeolitic imidazolate frameworks with graphene oxide (GO) nanosheets to prepare the composite structure. Pyrolyzing this structure generates a 3D porous carbon framework (PCF) composed of polyhedral‐shaped hollow carbon coated with reduced GO. The size of the polyhedral macropores can be adjusted from nanometer scale to micrometer scale. The PCFs generate a continuous network of heterostructured carbon with a large surface area and large pore volumes that are particularly useful as porous electrodes in lithium–sulfur batteries. The PCF/S composite electrode exhibits a high discharge capacity of 1151 mAh g−1 at 1 C and a low capacity decay of 0.035% per cycle after 650 cycles. [ABSTRACT FROM AUTHOR]

Mass interfacial processes have been considered as one of the crucial factors supporting fundamental research. Due to the low cost and conceptual simplicity, significant advancements have been achieved in the development of methodologies based on piezoelectric devices for in situ determination of mass changes on the surfaces of deposited materials under various conditions. The introduction of nanomaterials for designing sensors and monitoring systems becomes essential to create advanced detection systems for selective sensing of toxic analytes for environmental remediation. The integration of materials with predesignated nanostructures into sensor devices, such as surface acoustic wave (SAW), quartz crystal microbalance (QCM), and QCM with dissipation (QCM‐D) monitoring, has led to an immense progress in the sensing applications of toxic target analytes at the nanogram range. Here, an overview is introduced of recent advancement in the fabrication of piezoelectric devices for the interfacial mass sensing of targeted chemical vapors and ions through combination with nanoporous materials including mesoporous materials carbon‐based nanomaterials, metal–organic frameworks (MOFs), MOF‐derived nanoporous carbons, Prussian blue (PB) and its analogues (PBA), zeolites and related materials. Challenges and future prospect are also summarized by the advanced QCM technique associated with properties of nanostructured materials. [ABSTRACT FROM AUTHOR]

A flexible graphene (GN)-based film has been prepared by flow-directed assembly from a complex dispersion of GN and mesoporous carbon nanosphere (MCS) functionalized with poly dimethyl diallyl ammonium chloride. Morphology analysis displays that the presence of MCS has effectively prevent the restacking of individual GN sheets, favoring electrolyte ions easier access to the surfaces of GNs in forming electric double-layers. In application as a supercapacitor in 1 M KOH electrolyte, GN/MCS film shows superior electrochemical performance, including high specific capacitance (211 F g −1 at 0.2 A g −1 ), good rate capability (61% capacity retention at 20 A g −1 ) and excellent electrochemical stability (4% capacity loss after 5000 cycles). [ABSTRACT FROM AUTHOR]

The desulfurization performance and mechanisms of mesoporous g-C 3 N 4 as adsorbent in iso-octane solutions are presented. Mesoporous g-C 3 N 4 was synthesized at 600 °C with a hard-template method using three types of silica-gels as template agent. XRD diffraction patterns show the interlayer distances of g-C 3 N 4 are enlarged due to the intercalation of H + . The as-prepared adsorbents possess a large sulfur capacities and excellent selective adsorption for thiophene in a benzene/iso-ocatane mixed solution. TPD and regeneration experimental tests demonstrate that the larger sulphur-capacities could attribute to H + -intercalation. The adsorptive mechanisms of the thiophene over mesoporous g-C 3 N 4 are interpreted by a novel donor-acceptor (D-A) interaction, where the donor is the S-atom of thiophene and the acceptor is the C-atoms in g-C 3 N 4 . Gaussian computation indicates the ortho - C atoms of N-atoms bonded with H + are the main active sites for D-A interactions. [ABSTRACT FROM AUTHOR]

One-dimensional (1D) mesoporous ternary Co-Ni-Mn oxide nanowires (CNMO NWs) have been controllably fabricated via a facile yet scalable template-free strategy involving a green hydrothermal route coupled with the following calcination. The composition of the reaction solvent system, i.e., the volume ratio of the ethylene glycol and deionized water, plays a significant role in tuning the specific morphologies and microstructures of the final CNMO products. The as-derived lD CNMO NWs are constructed with numerous nanoparticle subunits with the size of ≈5-10 nm, and possess lots of interparticle mesopores ranged from 2 to 6 nm. The well-defined mesoporous CNMO NWs apparently have appealing structural advantages, such as fast and convenient electron and ion transport, sufficient redox electrochemical centers with multiple valences, and large electroactive surface area. As a result, the as-fabricated mesoporous CNMO NWs manifest exceptional pesudocapacitance and excellent cycling stability at high rates when evaluated as a striking low-cost electrode for next-generation electrochemical capacitors. [ABSTRACT FROM AUTHOR]

In this work, we rationally designed an efficient template-free synthetic strategy to fabricate hierarchical mesoporous hollow ZnMn2O4 sub-microspheres (HZSMs) constructed entirely from nanoparticle (NP) building blocks of size ≈15 nm. The well-known inside-out Ostwald ripening process was tentatively proposed to shed light on the formation mechanism of the mesoporous hollow nano-/microarchitecture. In favor of the intrinsic structural advantages, these resulting HZSMs exhibited superior electrochemical lithium-storage performance with high specific capacity, excellent cyclability, and good rate capability when evaluated as an anode material for advanced Li-ion batteries (LIBs). The excellent electrochemical performance should be reasonably ascribed to the porous and hollow structure of the unique HZSMs with nanoscale subunits, which reduced the diffusion length for Li+ ions, improved the kinetic process and enhanced the structural integrity with sufficient void space for tolerating the volume variation during the Li+ insertion/extraction. These results further revealed that the as-prepared mesoporous HZSMs would be a promising anode for high-performance LIBs. [ABSTRACT FROM AUTHOR]

Highlights: [•] Facile electrospinning method combined with soft-template self-assembly. [•] Abundant mesopores and large specific surface area. [•] Superior rate capability and excellent cycling stability. [ABSTRACT FROM AUTHOR]

Abstract: We developed a direct carbonization strategy to efficiently fabricate mesoporous N-containing carbon nanosheets (N-CNSs) by using polyaniline nanosheets as a carbon precursor. Physicochemical characterizations revealed that the as-synthesized N-CNSs with 5.9wt.% N species possessed a well-developed mesoporous architecture with large specific surface area of 352m2 g−1, high mesoporous volume of 0.32cm3 g−1, and average pore size of ∼5.2nm. When further utilized as an electrode for electrochemical capacitors, the mesoporous N-CNSs delivered a large specific capacitance of 239Fg−1 at 0.5Ag−1, and even 197Fg−1 at a high current load of 8Ag−1, indicating its good rate behavior. Furthermore, the capacitance degradation of ∼4% over continuous 5000 charge–discharge cycles at 6Ag−1 further verified its good electrochemical stability at high rates for long-term electrochemical capacitors application. [Copyright &y& Elsevier]

Abstract: The commercialization of lithium–sulfur (Li–S) battery has so far hindered by the low electrochemical utilization and rapid capacity fading of sulfur cathode, which is induced by low electric/ionic conductivity, high dissolution of intermediate polysulfides and the volume expansion of sulfur. Herein, we describe an on-site adsorption strategy toward superior stability of sulfur electrode by encapsulating elemental sulfur into mesoporous TiO2 host. Brunauer–Emmett–Teller (BET), transmission electron microscopy (TEM) and scanning transmission electron microscopy (STEM) measurements obviously indicate that elemental sulfur (S) occupy the mesopores of the TiO2 host, forming a core–shell liked nanostructure. The TiO2/S composite exhibits a superior cycling stability and high Coulombic efficiency during the charge/discharge process. Even at a high current rate of 1C, the TiO2/S composite shows an initial specific capacity of 650mAhg−1 and a specific retention of 89% after 100 cycles. The excellent electrochemical performances are critical related to the significant roles TiO2 host played during the electrochemical reaction. Firstly, the nano-sized TiO2 (∼5nm) traps the polysulfides via chemical bonding interaction to prevent their dissolution and minimize the “shuttle effect”. More importantly, the in situ formed Li x TiO2, acting as a mixed electric/ionic conductor, facilitates easier Li+/e− transport. The unique functions of the TiO2 plus its easy availability make the current study conceptually provides new opportunities to reach long-term cycling stability of sulfur cathode using carbon-free hosts. [Copyright &y& Elsevier]

Abstract: We developed a sacrificial template strategy to synthesize short NiO nanotubes (S-NiO NTs) with mesopores in sidewalls by using short carbon NTs as template for electrochemical capacitors. Further physical characterizations exhibited that as-synthesized S-NiO NTs owned a specific surface area of 150m2 g−1 and hierarchical (meso- and macro-) porosity. Electrochemical data presented that such NTs delivered a specific capacitance of 903Fg−1 at 1Ag−1, much larger than those of long NiO NTs and NiO nanoparticles. The capacity retention of ca. 88%, when the current density increased from 1 to 4Ag−1, indicated high rate capability of the unique S-NiO NTs electrode. Furthermore, a capacitance degradation of ca. 6% after 2000 charge–discharge cycles at 4Ag−1 demonstrated their desirable electrochemical stability. The short tubular and hierarchical porous feature of the S-NiO NTs resulted in the high electrochemical utilization for energy storage even at high rates. [Copyright &y& Elsevier]

Abstract: In the work, we develop a novel two-step strategy to synthesize self-supported hexagonal nickel oxide nanoplatelet arrays on Ni foam: precipitating hydroxides followed by calcinating process. These nanoplatelets are composed of a multilayer of ultrathin mesoporous NiO nanosheets. The unique Ni foam-supported mesoporous NiO nanoplatelet arrays electrode promises fast ion and electron transport, large electroactive surface area, and excellent structural stability. As a result, superior pseudocapacitive performance is achieved with large specific capacitance in the range of 1124–864Fg−1 and excellent cycling stability up to 5000 cycles, suggesting their promising application for electrochemical capacitors. [Copyright &y& Elsevier]

Abstract: Mesoporous Co3O4 nanowire (NW) arrays freely standing on Ni foam substrate are prepared via two-step strategy: precipitating hydroxides followed by calcinating process. The slim Co3O4 NWs with average diameter of about 80nm and length up to 10μm are observed by transmission electron microscopy and scanning electron microscopy. Cyclic voltammetry, chronopotentiometry, and electrochemical impedance measurements are applied to investigate the performance of the Co3O4 NW arrays. Electrochemical tests show that Co3O4 NW arrays deliver a specific capacitance (SC) of 1160Fg−1 at 2Ag−1, and even 820Fg−1 at 20Ag−1. Also, the SC degradation is only 9.6% after 5000 continuous charge–discharge cycles at 8Ag−1, indicating their excellent electrochemical stability. The improved performance is reasonably ascribed to their unique 3D hierarchical structure. [Copyright &y& Elsevier]

Abstract: In the work, amorphous CoS x nanodots were highly dispersed onto poly(sodium-4-styrene sulfonate) (PSS) functionalized multi-walled carbon nanotubes (FMWCNTs) by a interface-hydrothermal method. Electrochemical data demonstrated a specific capacitance (SC) of 300Fg−1 was delivered at 3Ag−1 by the nanocomposite, which was 90% of that at 0.4Ag−1, indicating its good rate response. The good dispersion of the electroactive CoS x nanodots onto the FMWCNTs should be responsible for its better supercapacitive performance. Such unique structure made the abundant electroactive surface atoms of the CoS x phase contacted by OH− ions and electrons easily through the three-dimensional mesoporous conducting matrix of FMWCNTs for fast energy storage. Furthermore, the SC retention of ca. 95% reveals a good electrochemical stability of the nanocomposite. [Copyright &y& Elsevier]