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The low cycling efficiency and uncontrolled dendrite growth resulting from an unstable and heterogeneous lithium-electrolyte interface have largely hindered the practical application of lithium metal batteries. In this study, a robust all-organic interfacial protective layer has been developed to achieve a highly efficient and dendrite-free lithium metal anode by the rational integration of porous polymer-based molecular brushes (poly(oligo(ethylene glycol) methyl ether methacrylate)-grafted, hypercrosslinked poly(4-chloromethylstyrene) nanospheres, denoted as xPCMS-g-PEGMA) with single-ion-conductive lithiated Nafion. The porous xPCMS inner cores with rigid hypercrosslinked skeletons substantially increase mechanical robustness and provide adequate channels for rapid ionic conduction, while the flexible PEGMA and lithiated Nafion polymers enable the formation of a structurally stable artificial protective layer with uniform Li

Lithium metal anode has attracted wide research interests because of its very high theoretical capacity and low potential. However, severe safety issues arising from lithium dendrite growth have gripped the throat of the practical application of lithium metal batteries. Herein, a novel superstructured single-ion conducting polymer brush (CNF-g-PSSLi) is proposed as artificial solid electrolyte interphase (SEI) film to inhibit the lithium dendrite growth. The as-obtained CNF-g-PSSLi integrates merits of robust CNF backbone nanonetwork, brush-improved interfacial compatibility, -SO3− group-guided rapid transportation of lithium ions, and -SO3− group-induced electrostatic repulsion against initially formed lithium dendrites. As a result, CNF-g-PSSLi film exhibits good mechanical properties (elasticity modulus = 5.3 GPa) against dendrite growth upon cell cycling, comfortable interfacial contact, and fast ionic transport. Symmetric Li|Li cells with CNF-g-PSSLi as artificial SEI show outstanding plating/stripping stabilities at ultrahigh current densities (20 mA cm−2). In addition, Li|LiFePO4 full cell with Li@CNF-g-PSSLi anode exhibits a long lifespan (300 cycles) with a tiny capacity decay of 0.08% per cycle at a high current density of 5 C. This work could provide an efficient attempt to develop superior artificial SEI films by well-orchestrated macromolecular engineering.

How to successfully achieve the effective construction and precisely control the pore structure of porous carbon materials based on advanced precursors, is still challenging. Herein, a kind of precise organic-inorganic hybrid nanospheres have been designed to synthesize activation-free and high-surface-area microporous carbon materials (MCMs), in which metastable silica-nanonetwork and confined phenyl are formed by the emulsion polymerization of phenyltriethoxysilane. Within this strategy, it is successful to realize the efficient formation of carbon framework, benefiting from the self-crosslinking of confined phenyl and the dual roles of metastable silica-nanonetwork. It is surprising that the silica-nanonetwork can act as the role of template, as well as cross-linker, making the obtained MCMs with high surface area (up to 2614 m2 g−1). Thus, as-prepared MCMs exhibit excellent performance as the electrode materials of supercapacitors in organic electrolyte, i.e. an energy density of 15.36 W h kg−1 at a power density of 27 kW kg−1.

Carbon‐based nanomaterials have been regarded as promising non‐noble metal catalysts for renewable energy conversion system (e.g., fuel cells and metal–air batteries). In general, graphitic skeleton and porous structure are both critical for the performances of carbon‐based catalysts. However, the pursuit of high surface area while maintaining high graphitization degree remains an arduous challenge because of the trade‐off relationship between these two key characteristics. Herein, a simple yet efficient approach is demonstrated to fabricate a class of 2D N‐doped graphitized porous carbon nanosheets (GPCNSs) featuring both high crystallinity and high specific surface area by utilizing amine aromatic organoalkoxysilane as an all‐in‐one precursor and FeCl3·6H2O as an active salt template. The highly porous structure of the as‐obtained GPCNSs is mainly attributed to the alkoxysilane‐derived SiO x nanodomains that function as micro/mesopore templates; meanwhile, the highly crystalline graphitic skeleton is synergistically contributed by the aromatic nucleus of the precursor and FeCl3·6H2O. The unusual integration of graphitic skeleton with porous structure endows GPCNSs with superior catalytic activity and long‐term stability when used as electrocatalysts for oxygen reduction reaction and Zn–air batteries. These findings will shed new light on the facile fabrication of highly porous carbon materials with desired graphitic structure for numerous applications., 2D N‐doped graphitized porous carbon nanosheets (GPCNSs) featuring both high crystallinity and high specific surface area are prepared by molecular engineering. The unusual integration of graphitic skeleton with porous structure endows GPCNSs with superior catalytic activity and long‐term stability when used as electrocatalysts for oxygen reduction reaction and Zn–air batteries.

Advanced antimicrobial agents that treat infectious diseases are greatly needed. Various silver-based nanomaterials have been developed and are considered potential candidates for many commercial products, but they lack durability and adequate antibacterial activity. A new class of nanohybrids of silver nanoparticles (AgNPs) grown in-situ on graphene oxide (GO) using a silver ion salt was synthesized by a simple ultrasonic mixing method. The structure and composition of the nanohybrids were investigated by SEM, TEM, FTIR, TGA, XRD and XPS. Results indicated that GO acts not only as a negatively charged macromolecule for capturing Ag+ ions, but also a reducing agent to reduce the Ag+ ions to AgNPs. The heterogeneous structure leads to abundant well-dispersed AgNPs and Ag+ ions on the GO support. The as-prepared nanohybrids make full use of the advantages of both AgNPs and GO-Ag+ salts, leading to improved and long-term antibacterial activity against both S.aureus and E. coli.

A kind of three-dimensionally nanostructured carbon materials (3DNCMs) with tube-in-tube structure was fabricated based on a novel structural design and precise control of ternary bottlebrushes by surface-initiated atom transfer radical polymerization (SI-ATRP). The 3D interconnected network of 3DNCMs consists of the hybrid carbon framework with unique tube-in-tube structure rooting from the ternary bottlebrushes and the microporous carbon shell generated from the carbonization of hypercrosslinked polystyrene (PS). The nanostructure of 3DNCMs can be changed precisely by controlling the ternary bottlebrush structures. The tube-in-tube structure provides 3DNCMs an abundant of microspores within outer amorphous carbon tube and a lot of mesopores from the removal of coated silica, which favor for the hosting of sulfur element. Moreover, carbon nanotubes, the core of the tube-in-tube structure, afford the 3DCNMs with excellent electrical conductivity. In view of the prominent advantages of the tube-in-tube structure, the sulfur cathode based on 3DNCMs hosts shows a remarkable rate capability and reversible discharge capacity of 691 mAh g−1 after 200 cycles at a 2 C current density. We hope this concept of novel design and construction of well-defined nanostructure will pave the way toward high-performance nanoporous carbon materials for energy storage and other practical applications.

Nowadays, it has been more and more important to ingeniously design sheet-like structures since the performance of many modern materials fundamentally depends upon the exploitation of these structures. In this work, we have successfully developed a facile and effective strategy for fabricating a class of 2D porous carbon nanosheets that simultaneously exhibit high surface areas and uniform distribution of metal chalcogenides for superior oxygen evolution reaction. The synthesis of these 2D carbon nanosheets involves the in-situ metal ion adsorption and exchange by the sulfonate radicals of polymer sheets followed by carbonization to form a series of metal chalcogenides loaded porous carbon nanosheets (PCNs/MxSy). The abundant mesopores (e.g., 3–7 nm, 524 m2 g−1) that derived from the spontaneous stacking of flexible GO precursor are advantageous to the exposure of heteroatom sites. The uniform catalytic sites (33.8 nm) formed in-situ effectively avoid the agglomeration of functional components, which are conducive to make full use of catalytic sites and consequently shows excellent OER performance. We hope that our novel strategy can open a new door for the application and innovation of fabricating 2D porous carbon nanosheets in a wide range of areas including energy storage, adsorption, catalysis, separation and so on.

Atom transfer radical polymerization was utilized to prepare well-defined cylindrical molecular bottlebrushes which were employed as building blocks and transformed into porous nanonetwork-structured carbons (PNSCs) via hypercross-linking chemistry and shape-regulated carbonization. The as-prepared PNSCs exhibited a unique nanomorphology-tunable characteristic by simply varying carbonization conditions. Because of their three-dimensional network nanomorphologies with well-developed hierarchical porous structures and conductive carbon framework, the PNSCs demonstrated excellent electrochemical performance in lithium-sulfur batteries.

Development of efficient, low-cost, and durable electrocatalysts for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) is scientifically and technologically important for the conversion and storage of renewable energy. Herein, cobalt and nitrogen codoped ultrathin porous carbon nanosheet (Co-N-PCN) is developed by directly carbonizing the graphene oxide sandwiched cobalt ion adsorbed polyaniline-co-polypyrrole (PACP) precursors. The nitrogen-rich PACP favors the formation of abundant Co-Nx-C active species, while the 2D ultrathin nanosheet structure ensures the high exposure of the generated Co-Nx-C active sites to the electrolyte. In addition, the sandwiched graphene acts as the conductive backbone to facilitate fast charge transfer and enhance the electrode conductivity. Benefiting from the synergistic effect, the Co-N-PCN presents superior electrocatalytic properties with low overpotentials and favorable kinetics to Pt and RuO2 as a bifunctional electrocatalyst for ORR and OER. Remarkably, the potential difference of OER and ORR (ΔE = Ej=10 - E1/2) is as low as 0.81 V in 0.1 M KOH, indicating the Co-N-PCN outperforms most of the previously reported bifunctional electrocatalysts.

A simple yet efficient interfacial crosslinking strategy was developed to fabricate an ultrathin two-dimensional composite in which silicon nanoparticles are uniformly enwrapped in silicon oxycarbide nanosheets (Si/SiOC-NS). The conceptual interfacial crosslinking strategy includes polymeric precipitation at the oil/water interface and simultaneous in situ crosslinking of organosilicon polymers, which overcomes the bottleneck of the conventional sol–gel method to synthesize 2D precursors for SiOC. Moreover, the nanostructures of precursors are well-controlled because of the facile precipitation process. The high aspect ratio of the as-obtained Si/SiOC-NSs exposes a large surface to the electrolyte and facilitates the penetration and diffusion of Li ions around Si nanoparticles. The stable SiOC matrix not only buffers the volume changes of active materials during the charge–discharge process but also contributes to lithium storage. As a result, the anodes of LIBs based on Si/SiOC-NS deliver excellent rate capability (a high capacity retention rate of 65% at 1 A g−1 in comparison with that 0.1 A g−1) and a long lifetime of 500 stable cycles with high capacities at a large current density of 5 A g−1.

Nitrogen-doped porous carbon spheres have attracted great interest in diversified fields owing to their unique physical and chemical properties. However, the synthesis of nitrogen-doped porous carbon spheres with hierarchical superstructures and refined micropore structures is still a challenge. Herein, we develop a molecular-scale silica templating strategy to prepare nitrogen-doped microporous carbon spheres (MCSSs) with high porosity and a well-defined micropore structure. Octa(aminophenyl) polyhedral oligomeric silsesquioxane is used as a building block in MCSS precursors to provide precise molecular-scale templating and nitrogen doping. The morphology of MCSSs can be easily tuned by choosing the proper solvent. The as-synthesized MCSS with a large surface area (2036 m

Porous carbon nanosheets have the advantages of longitudinal continuity, transverse ultrathin, high specific surface area, and surface atomic activity, as well as the synergistic effect of micro and nanoproperties, so the research on their preparation, structure, and properties has attracted wide attention. A series of ultrathin hierarchical porous carbon nanosheets (HPCNs) is fabricated through carbonization of precursors obtained through the Friedel-Crafts reaction-assisted loading of polystyrene on graphene oxide. Hierarchical pore structures consist of three parts: (1) the micropores (1.3 nm), which were provided by porous polystyrene through the Friedel-Crafts reaction; (2) the mesopores (3.8 nm), which were provided by slab pores from the stack of carbon nanosheets; and (3) the pores (5 nm) formed from the random stack of carbon nanosheets. Controlling the carbonization time and temperature adds to a prominent increase in specific surface area from 405.8 to 1420 m

Pyrite FeS2 is a promising alternative to typical intercalation cathodes for rechargeable lithium-ion batteries (LIBs) by virtue of its extremely high theoretical capacity. However, the inferior rate capability and fast capacity degradation caused by the sluggish reaction kinetics and large volume expansion upon lithiation greatly hinder its practical application. Herein, a chemical crosslinking strategy is developed for the synthesis of the yolk-shell pyrite FeS2@porosity-rich sulfur-doped carbon nanonetworks (FeS2@C NNs) as cathode materials for high-performance LIBs. The 3D nanonetwork structure constructed by tight covalent connection of carbon shells can act as highways to facilitate the electron transport kinetics, while the well-orchestrated internal cavities of the yolk-shell nanostructure provide large void space to accommodate the volume expansion of pyrite FeS2. In addition, the porosity-rich characteristic of carbon shells ensures fast pathways for the Li+ diffusion across the shells. As a result, the yolk-shell FeS2@C nanonetworks exhibit excellent high-rate capability (353 mAh g−1 at 10 C) and exceptionally long lifespan of 1000 cycles with a high capacity of 435 mAh g−1 at a large current density of 5 C, which is by far the best of pyrite FeS2-based cathodes for LIBs.

Porous nanostructured carbon materials exhibit unique structural features such as high surface area and excellent physicochemical stability and have been of significantly scientific and technological interest because of their vital importance in many energy related applications. Synthetic polymers represent a major class of precursors for developing cutting-edge porous carbons, among which conjugated polymers have emerged as an attractive family of carbon precursors. Distinct from those typical polymer precursors, the robust conjugated structure ensures sufficient framework carbonizability and nanoarchitecture-conserving stability during carbonization process, which is crucial to the successful transformation of designed polymer architectures to finally desired carbon nanostructures. Moreover, heteroatom doping (e.g., N, S, B, and metals) or codoping can be naturally integrated into carbon framework directly by using the heteroatom-containing monomers. Especially, using the newly emerged structurally defined carbon-rich conjugated porous networks as precursors, precise control of compositions and structures of carbon materials becomes possible even at the molecular level. In this review, we will highlight recent strategies to the preparation of porous carbon materials with well-defined porous nanostructures using conjugated polymers as versatile precursors. Beginning with a brief introduction to these precursors, including linear-type conjugated polymers and conjugated porous networks, the synthetic techniques for the fabrication of porous nanostructured carbons by direct templating, self-assembly, template-free, chemical activation, and microwave irritation approaches, will be reviewed. Meanwhile, the sophisticated nanomorphologies, precisely controlled porous structures, and custom-designed functionalities of these conjugated-structure-derived carbons, together made them amenable to diverse task-specific applications, such as electrocatalysis, Li-ion batteries, supercapacitors, and adsorption. Finally, a perspective of the research directions in this field will be presented.

Carbon aerogels and their precursory polymer aerogels are an important class of porous materials, because they have a unique three-dimensional interconnected nanonetwork structure that can minimize diffusive resistance to mass transport. However, production of conventional aerogels in a monolithic form remains problematic, because of risk of explosive polymerization, tedious supercritical/freeze drying steps, extra ball milling, and difficulty in controlling micro/nanostructures. Here we show that novel powdery carbon aerogels and their polymer aerogel precursors have been developed by utilizing shape-persistent nanoparticles as building blocks, followed by hypercrosslinking for forming a well-defined 3D interconnected nanonetwork with numerous interstitial nanopores and intraparticle micropores. The resulting aerogels are in a microscale powdery form. The preparation route is much more feasible for scaling up, due to avoidance of explosive polymerization and facile drying at ambient pressure. By simple carbonization, powdery carbon aerogels can be obtained with a high surface area of 2052 m 2 g −1 . Benefiting from structural advantages, the aerogels demonstrate excellent electrochemical performances in supercapacitors and lithium-sulfur batteries.

It remains a formidable challenge to construct advanced adsorbents with superb adsorption, environmental stimuli response, and real-time detection capability for efficiently treating contaminants from complex environmental systems. A novel class of an all-in-one microporous adsorbent that simultaneously has excellent environmental chemosensory responsivity, visual detectivity, superfast micropollutant adsorption, as well as easy regeneration is reported herein. The advanced microporous adsorbent discussed in this study presents a hairy nanospherical morphology composed of a hairy stimuli-responsive polymeric shell and a shell-assisted superadsorptive microporous core. The adsorbent not only exhibits a valuable capability of pollutant detection by visible fluorescence quenching, but can also remove organic micropollutants from polluted water with super-rapid speed (79%, 98%, and 100% of its equilibrium uptake in 7 s, 10 s, and 2 min, respectively) and excellent recyclability (>96%). More importantly, the adsorbent still shows unimpeded adsorption performance in the flow-through adsorption tests (15 mL min-1 ), indicating a very appealing application prospect.

Exploring advanced porous materials is of critical importance in the development of science and technology. Porous polymers, being famous for their all-organic components, tailored pore structures, and adjustable chemical components, have attracted an increasing level of research interest in a large number of applications, including gas adsorption/storage, separation, catalysis, environmental remediation, energy, optoelectronics, and health. Recent years have witnessed tremendous research breakthroughs in these fields thanks to the unique pore structures and versatile skeletons of porous polymers. Here, recent milestones in the diverse applications of porous polymers are presented, with an emphasis on the structural requirements or parameters that dominate their properties and functionalities. The Review covers the following applications: i) gas adsorption, ii) water treatment, iii) separation, iv) heterogeneous catalysis, v) electrochemical energy storage, vi) precursors for porous carbons, and vii) other applications (e.g., intelligent temperature control textiles, sensing, proton conduction, biomedicine, optoelectronics, and actuators). The key requirements for each application are discussed and an in-depth understanding of the structure-property relationships of these advanced materials is provided. Finally, a perspective on the future research directions and challenges in this field is presented for further studies.

Novel MnO multi-core@nitrogen-doped carbon shell nanoparticles (MC N C m SPs) were developed through a facile polydopamine adhesive-assisted compositing procedure. Owing to their advanced multi-core@shell nanostructure, the as-prepared MC N C m SPs exhibited remarkable electrochemical performance as lithium-ion battery anode.

A novel active yolk@conductive shell nanofiber web with a unique synergistic advantage of various hierarchical nanodimensional objects including the 0D monodisperse SiO2 yolks, the 1D continuous carbon shell and the 3D interconnected non-woven fabric web has been developed by an innovative multi-dimensional construction method, and thus demonstrates excellent electrochemical properties as a self-standing LIB anode.

Carbon aerogel (CA) with 3-D continuous skeleton and mesopore structure was prepared via a microemulsion-templated sol–gel polymerization method and then used as the anode materials of lithium-ion batteries. It was found that the reversible specific capacity of the as-prepared CAs could stay at about 470 mA h g −1 for 80 cycles, much higher than the theoretical capacity of commercial graphite (372 mAh g −1 ). In addition, CA also showed a better rate capacity compared to commercial graphite. The good electrochemical properties could be ascribed to the following three factors: (1) the large BET surface area of 620 m 2 g −1 , which can provide more lithium ion insertion sites, (2) 3-D continuous skeleton of CAs, which favors the transport of the electrons, (3) 3-D continuous mesopore structure with narrow mesopore size distribution and high mesopore ratio of 87.3%, which facilitates the diffusion and transport of the electrolyte and lithium ions.

Both high surface areas and well-orchestrated nanomorphologies are important for porous organic polymers (POPs). However, the two key characteristics are generally difficult to be satisfied simultaneously, because the common pore-making procedures usually produce ill-defined nanomorphologies or give rise to damage of precustomized nanomorphologies. Herein, a facile yet versatile stepwise crosslinking strategy for fabrication of POPs with an unusual nanomorphology-persistent characteristic during pore-making is reported. Polystyrene nanofibers and poly(styrene-co-divinylbenzene) nanosphere arrays are utilized as building blocks, and then transformed into nanofibrillar morphology-persistent and ordered array morphology-persistent POPs via stepwise crosslinking, respectively. The stepwise crosslinking strategy includes pre-crosslinking and hypercrosslinking; the pre-crosslinking in a carefully selected poor solvent of polystyrene forms a lowly crosslinked structure, which guarantees the stability of nanomorphology during the subsequent pore-making via hypercrosslinking. The as-obtained POPs can be used as precursors for novel well-defined hyperporous carbon nanofibers and ordered carbon nanosphere arrays with excellent adsorption performances.

As an important method for preparing ordered mesoporous polymeric and carbonaceous materials, the organic template directed self-assembly is facing challenges because of the weak noncovalent interactions between the organic templates and the building blocks. Herein we develop a novel reactive template-induced self-assembly procedure for fabrication of ordered mesoporous polymer and carbon materials. In our approach, the aldehyde end-group of reactive F127 template can react with the resol building block to in-situ form a stable covalent bond during the self-assembly process. This is essential for an enhanced interaction between the resol and the template, thus leading to the formation of an ordered body-centered cubic mesostructure. We also show that the ordered mesoporous carbon product exhibits superior capacitive performance, presenting an attractive potential candidate for high performance supercapacitor electrodes.

Ordered mesoporous carbon/carbon aerogel (OMC/CA) composites have been obtained by a simple ultrasonic mixing technique. It is found that there exists a synergistic effect between OMC’s channel-like mesopores and CA’s network-like mesopores during electrochemical charge–discharge process; and the maximum synergistic coefficient arrives at 0.37 when CA content is 30 wt.%. As a result, the as-prepared OMC/CA composites can make full use of the two-dimensional order of mesoporous structure of OMC and the three-dimensional connectivity of mesoporous structure of CA, and thus, exhibit much better electrochemical properties as compared to OMC and CA alone.

A one-step nanocasting method to prepare a bimodal mesoporous carbon from a highly hydrophobic carbon precursor, i.e., petroleum pitch, has been successfully developed by adopting tetrahydrofuran and hydrofluoric acid as solvent and catalyst, respectively, for the gelation reaction of tetraethyl orthosilicate and water. Experimental results show that the introduction of proper amounts of petroleum pitch does not hamper this gelation reaction, thus forming a uniform silica/carbon composite. It was found that the as-prepared nanoporous carbon has a three-dimensional 3.4 nm-sized wormholelike mesoporous network with well-distributed 17.1 nm-sized particlelike mesopores. Such a bimodal mesoporous carbon has a high Brunauer–Emmett–Teller surface area (782 m2 g−1) and a very large total pore volume (3.0 cm3 g−1).

Lithium-sulfur (Li-S) batteries, based on the redox reaction between elemental sulfur and lithium metal, have attracted great interest because of their inherently high theoretical energy density. However, the severe polysulfide shuttle effect and sluggish reaction kinetics in sulfur cathodes, as well as dendrite growth in lithium-metal anodes are great obstacles for their practical application. Herein, a two-in-one approach with superhierarchical cobalt-embedded nitrogen-doped porous carbon nanosheets (Co/N-PCNSs) as stable hosts for both elemental sulfur and metallic lithium to improve their performance simultaneously is reported. Experimental and theoretical results reveal that stable Co nanoparticles, elaborately encapsulated by N-doped graphitic carbon, can work synergistically with N heteroatoms to reserve the soluble polysulfides and promote the redox reaction kinetics of sulfur cathodes. Moreover, the high-surface-area pore structure and the Co-enhanced lithiophilic N heteroatoms in Co/N-PCNSs can regulate metallic lithium plating and successfully suppress lithium dendrite growth in the anodes. As a result, a full lithium-sulfur cell constructed with Co/N-PCNSs as two-in-one hosts demonstrates excellent capacity retention with stable Coulombic efficiency.

Bimodal mesoporous carbons were successfully prepared by a simple one-step templating method. The template of large mesopores in our method is the in situ formed silica nano-agglomerate from the drying-induced collapse of superfluous silica frameworks. Moreover, the diameter of large mesopores can be easily tailored by the ratio of methylated β-cyclodextrin to tetramethyl orthosilicate (CD/TMOS), increasing with decreasing the CD/TMOS. The typical bimodal mesoporous carbons with 2.4 nm and ca. 24 nm diameter mesopores have great Brunauer–Emmett–Teller surface areas (e.g. 783 m 2 /g) and large mesopore volumes (e.g. 2.18 cm 3 /g).

Morphology and porous structure of the pitch-based carbon aerogels (CAs) were characterized by scanning electron microscopy (SEM) and N2 adsorption–desorption measurement. Their electrochemical performances as electric double-layer capacitor (EDLC) electrodes were studied by cyclic voltammetry and galvanostatic charge–discharge measurements. It was found that the particle size of the CAs decreased with the increase of the volume ratio of toluene to acetic acid (T/A ratio). The BET surface areas of the obtained CAs were in the range of 290–450 m2 g−1. CA electrodes had good electrochemical performance and appropriate specific capacitance. Moreover, the electrochemical performance of the CAs was enhanced by the existence of extensive mesoporous networks of the CAs. CA with 2.23 of T/A ratio had the highest specific capacitance, i.e., 131.9 F g−1 for cyclic voltammetry. Thus, it was thought that the pitch-based CAs were suitable electrode materials for EDLCs.

A series of organic aerogels (AGs) with different porous structures were prepared by controlling the conditions of sol–gel polymerization, and related carbon aerogles (CAs) were obtained by carbonization at 1,173 K. Their structures were investigated by N2 adsorption–desorption analysis. The static adsorption of theophylline from aqueous solution on AGs and CAs was studied to explore the influence of micropore areas, mesopore volume and surface chemistry on adsorption capacity. The results show that the adsorption capacities of theophylline on CAs are better than on AGs. The adsorption properties of all samples obey Langmuir model. The values of correlation coefficient are almost over 0.99, indicating a good mathematical fit. The comparison of the adsorptions on AGs and CAs indicated that both micropores and mesopores play important roles in determining the adsorption capacity. But for AGs, besides the pore structure, the surface chemistry also contributes to the adsorption capacities.

A carbon aerogel (CA) loaded with platinum nanoparticles can achieve good catalytic performance in proton exchange membrane fuel cells. Pt–Ru bimetallic nanoparticles were loaded onto a carbon aerogel through a simple process. The PtRu/CA achieved good cell performance when used as a direct methanol fuel cell anode catalyst. The advantages of carbon aerogel may be attributed to the mesopore structure that can facilitate the mass transportation in the electrode. The Ru content in the catalyst has a great influence on its performance. The PtRu/CA with 25 at.% Ru achieves the best cell performance at 30 °C.

In this paper, we investigated the requirements of organic gels for a successful ambient pressure drying by analyzing the role of the strength, the pore size and the surfactant of organic gels in decreasing the drying shrinkage of organic aerogels. Experimental results showed the effect of the decrease of the surface tension, resulting from the surfactant, on the drying shrinkage was very small and negligible. The drying shrinkage depended strongly on the strength and the pore size. Subsequently, the respective role of the strength and the pore size was evaluated. It can be found that the strength plays a greater role than the pore size.

A new class of nitrogen-doped ordered mesoporous carbon/silica (N-OMC/SiO2) nanocomposites was successfully fabricated via a multi-constituent co-assembly strategy. The N-OMC/SiO2 nanocomposite presented a unique interpenetrating carbon/silica structure whose carbon/silica interface is highly uniform, and thus demonstrated high capacity, good cycling and excellent rate properties.

An improved method of preparing phenol–furfural aerogels and related carbon aerogels was developed by dividing the sol–gel polymerization into two steps, i.e., the formation of gel precursors by prepolymerizing phenol and furfural with NaOH as a catalyst and subsequently the gelation of the precursors with HCl as a catalyst. The role of the cross-link density of the gel precursors in the preparation process was studied by investigating its effects on the yield, the drying shrinkage, the bulk density and the texture of organic and carbon aerogels obtained here. It was found that a proper increase in the cross-link density of the gel precursors by prepolymerizing with NaOH as a catalyst helps to increasing the yield of organic and related carbon aerogels but leads to an increase of the bulk density of organic and carbon aerogels. The nano-particle size and mesoporosity of organic and related carbon aerogels can be improved by an appropriate increase in the cross-link density of the gel precursors. But, the organic aerogels with a NaOH-catalyzed prepolymerization process (NCPP) experience a larger drying shrinkage than those without the NCPP.

We have developed a method that would allow for the fabrication of carbon aerogel (CA) spheres. The inverse phase suspension polymerization of resorcinol and formaldehyde monomers with Na 2 CO 3 as a catalyst followed by supercritical drying was explored. The effects of the chemical formulation and processing procedures and the conditions of the structures of organic and related carbon aerogels were studied. The experimental results indicated that it was easy to avoid the accumulation of polymerization heat during gelation, and easy to take out the products from the reaction container, through this fabrication method. Sol–gel microspheres with diameters ranging from about 30–1000μm could be obtained. After drying the sol–gel spheres under alcohol supercritical drying conditions, aerogel spheres with a bulk density of 0.8–1.0 g/cm 3 were prepared, and by subsequently pyrolyzing them, CA spheres with surface areas of 250–650 m 2 /g were obtained. The resultant CA spheres could be used as the electrode materials of supercapacitors. The specific capacitance of the CA spheres was as high as 215 F/g, and the equivalent series resistance at 48 Hz was about 1 Ω.

Carbon aerogels were successfully fabricated by a microemulsion-templated sol–gel polymerization method. When a suitable molar ratio of surfactant to resorcinol (S/R) and an appropriate resorcinol–formaldehyde concentration were selected, the organic gels thus obtained could be dried with little shrinkage by heating at ambient pressure. The size of carbon nano-particles and the pore size of carbon aerogels thus produced decrease with an increase of S/R. The highest specific surface area and specific mesopore volume of the carbon aerogels prepared by our method were 620 m 2 g −1 and 1.14 cm 3 /g, respectively.

A new class of conductive composites with good gas sensitivity was fabricated by filling polystyrene with vapor grown carbon nanofibers (VGCNF). A solution mixing/solvent removal procedure was used. VGCNFs form conductive networks at fiber loadings above the percolation limit within the matrix. Greatly improved conductivity is achieved relative to the same volume fraction of carbon black addition when these fibers are distributed to give reasonably uniform dispersions in the matrix. The high aspect ratios of these fibers (∼70–250 nm diameters and 5–75 μm lengths) assist in forming low wt.% percolation thresholds (below 1 wt.% fiber). Excellent gas sensitivity with 10 4 –10 5 times higher than the original resistance value in many saturated organic vapors and a maximum resistance response of about 1.1 × 10 5 times exposure to saturated THF vapor at 6.25 wt.% of VGCNF in the polystyrene matrix was observed. The maximum resistance response declined from about 2.0 × 10 5 times at 15 °C to about 3.4 × 10 4 times at 55 °C. These composites exhibited stable and reusable gas sensitivity to THF vapor. Carbon black/polystyrene composites exhibit a negative vapor coefficient (NVC) upon swelling caused by filler redistribution. In contrast, VGCNF/polystyrene composites are more stable, with much smaller NVC values due to their high aspect ratios and reinforcing effects which stabilize electrical percolation pathways. Thus, VGCNF/organic polymer composites are good gas sensor candidates for detecting organic vapors.

Phenol can be used as a cheap raw material to prepare organic and carbon aerogels based upon the gelation and supercritical drying in ethanol. In addition, organic and carbon aerogels could also be obtained by directly drying phenol-furfural alco-gels at ambient pressure under proper preparation conditions. The effect of the preparation conditions, such as the phenol-furfural (PF) concentration, the mass ratio of HCl to phenol (HCl/P), the mole ratio of phenol to furfural (P/F) and the gelation temperature, on the gelation ability and the bulk density was studied. The aerogels obtained have a three-dimensional network that consists of approximately 20 nm particles, which define numerous mesopores with diameter less than 50 nm. Organic aerogels obtained have high BET surface areas of 267–503 m/g and large mesopore volumes of 0.657–2.734 cm/g. Carbonization generates numerous micropores of ca. 0.45 nm in diameters but impairs to some extent the mesopore structure. As a result, carbon aerogels have high BET surface areas of 507–561 m/g, large micropore volumes of 0.106–0.168 cm/g and small mesopore volumes of 0.505–0.710 cm/g relative to their organic aerogel precursors. XRD characterization indicates that carbon aerogels are more crystalline than activated carbon but less than graphite.

Silver-dispersed carbon aerogels (CAs) were obtained by direct immersion of organic aerogels prepared by ambient pressure drying technique in AgNO3 aqueous solution and then carbonization. The effect of preparation conditions such as the resorcinol/catalyst ratio, the feed AgNO3 concentration, the ratio of aerogel mass/solution volume, immersion time and carbonization temperature on the bulk density and silver content as well as the BET surface area of the dispersed CAs was studied. The dispersion and structure of silver nanoparticles in obtained materials were investigated by means of scanning electron microscopy, transmission electron microscopy and X-ray diffraction. The Ag-dispersed CAs prepared exhibit strong and long-term antibacterial activity.

With the addition of hexamethylenetetramine (HMTA) and alcohol as solvent, an ambient pressure drying technique was developed for the fabrication of low-density organic aerogels and related carbon aerogels. When a suitable ratio of resorcinol to HMTA (R/H ratio) and ratio of resorcinol to solvents (R/S ratio) are selected, the low-density alco-gels obtained can be dried under ambient pressure conditions without observable shrinkage. The addition of HMTA increases the size of carbon nano-particles and the pore size of the aerogels that are produced. The carbon aerogels prepared in this work have similar nano-particle structures typical of the aerogels prepared with CO 2 or by the isopropanol supercritical drying technique.

Activated carbon fiber/carbon aerogel (ACF/CA) composites were fabricated by gelling a mixture of ACF and resorcinol and furfural, followed by supercritical drying of the mixture in isopropanol. The product then went through carbonization in a nitrogen atmosphere. The fabrication conditions, such as the mass content of R–F, the content of the ACF added, and the gelation temperature, were explored. The textures and pore structures of the ACF/CA composites thus obtained were characterized using transmission electron microscopy, scanning electron microscopy, and a surface area analyzer. The mechanical properties of the samples were assessed primarily through compressive tests. The experimental results indicated that the added ACF disperses uniformly in the resulting ACF/CA composites. The carbon matrix of the ACF/CA composites also consisted of interconnected carbon nanoparticles with sizes in the range of 20 to 30 nm. The ACFs can reinforce the related carbon aerogels when they originally have low mass density and are weak in mechanical strength. When large amounts of ACF were added to the composites, the micropore area and micropore volume of the composites increased, but their external surface area decreased. The mesopore volumes and the related diameters and mesopore size distributions of the ACF/CA composites were mainly affected by the mass density of the composites. The micropore sizes of all the composites were sharply concentrated at about 0.5 nm.

Copper-doped carbon aerogels were investigated by X-ray photoelectron spectroscopy to determine the chemical nature and distribution of the copper species in the aerogel framework. The Cu2p spectra of both the organic and carbon aerogels show a fairly uniform distribution of copper species in the aerogel network, with a slight increase in copper content going from the edge to the center of the monolith. The O1s spectra of the copper-doped organic aerogel indicate that both the carboxyl and hydroxyl groups of the aerogel framework are involved in chelation of the copper ions. After carbonization, the content of the copper detected by XPS decreases significantly as the copper ions are reduced into metallic copper nanoparticles. These nanoparticles are difficult to detect by XPS because they are coated by a thin carbon layer and migrate into the carbon matrix. The carbon skeleton of the copper-doped carbon aerogels is mainly composed of a uniform micro-graphite-like crystalline network, and no copper−carbon ...

We have prepared carbon aerogels (CAs) doped with copper through sol−gel polymerization of formaldehyde with the potassium salt of 2,4-dihydroxybenzoic acid, followed by ion exchange with Cu(NO3)2,...

Cu-loaded carbon aerogel was prepared by soaking sol-gel production, obtained from K-salt of 2,4-dihydroxybenzoic acid, into Cu(NO 3 ) 2 solution. XPS measurement demonstrated that Cu concentration is higher in the outside region of bulk samples, indicating that Cu may be incorporated through an immersing process rather than ion-exchanging. TEM observation showed that, like an aerogel sample with K ions, Cu-loaded organic aerogels had porous texture in which gel particles about 20-30nmo were interconnected with each other. Metal-loading process used in this study was considered as a promising method to disperse metals without changing original structure of carbon aerogels.

A simple and effective way to introduce micropores into skeleton of carbon aerogel (CA) without damaging its unique 3D mesoporous nanonetwork has been successfully developed by NH3-assisted semicarbonization. During the NH3-assisted semicarbonization process, nitrogen functional groups with high thermo-decomposable ability like pyrrolic/pyridine and pyridinic can be introduced into the semicarbonized aerogel framework by substituting oxygen functional groups with low thermo-decomposable ability like C═O quinone-type groups and then escape from the resultant CA framework during the subsequent carbonization, thus forming abundant micropores inside carbon framework under the circumstance of keeping wonderful stability of mesoporous nanonetwork structure. Compared with the traditional CA without NH3 assistance during semicarbonization, the as-prepared novel CA represents a much higher surface area (1100 vs 620 m(2) g(-1)) and a compatible mesopore structure. Meanwhile, such a NH3 treatment confers many useful nitrogen functional groups on the nanonetwork framework. The novel CA is then used as electrode material of supercapacitors and shows a much higher capacitance and comparable high capacitance retention as compared with the traditional CA.

A simple and efficient method to tailor the pore size of wormholelike mesoporous carbons (WMCs) has been developed by adding a proper amount of hydrofluoric acid (HF) during the sol-gel process of tetraethyl orthosilicate (TEOS). It was found that the pore size increased obviously from 3.1 to 8.5 nm when increasing HF/TEOS molar ratio from 0 to 1/7. Brunauer–Emmett–Teller surface area decreased accordingly. In addition, mesopore volume of WMCs basically kept unvaried due to their identical silica template amount.

Activated ordered mesoporous carbons with a channel structure (AOMCs-CS) were successfully prepared by imposing CO(2) activation on ordered mesopore carbon C-FDU-15. It is found that the continuous carbon framework of the precursor C-FDU-15 plays an important role in keeping the order structure of the resulting AOMCs-CS. The mild activation (e.g., 31 wt % burnoff) does not impair the order degree. After that, the order degree gradually decreases with further increasing burnoff. However, the basic hexagonal mesostructure of C-FDU-15 can still be found in the AOMCs-CS when the burnoff is up to 73 wt %, although many carbon walls are punched and thus many larger mesopores and marcropores are generated. With increasing burnoff, the surface area and volume of micropores increase first and then decrease, and the surface area and volume of mesopores continuously increase. The highest measured Brunaruer-Emmett-Teller (BET) surface area, micropore volume, and total pore volume of the AOMCs-CS reach 2004 m(2)/g, 0.50 cm(3)/g, and 1.22 cm(3)/g, respectively.

采用浓硝酸对层次孔炭气凝胶(HPCA-1)进行表面改性,制备了新型表面改性层次孔炭气凝胶(mHPCA-1),并进一步研究了mHPCA-1对酸性品红(AF)的吸附行为.结果表明,浓硝酸表面改性对炭气凝胶的纳米形貌和孔结构影响不大,但可以明显提高炭气凝胶的表面含氧官能团数量,从而优化层次孔表面化学性质,使得mHPCA-1对AF表现出更高的吸附量.mHPCA-1对AF的等温吸附过程符合Langmuir方程,其对AF的吸附属于单分子层吸附,最大吸附量可达191.57 mg·g-1,明显高于HPCA-1(120.92 mg·g-1).吸附动力学结果证实了浓硝酸表面改性可以显著提升层次孔炭气凝胶对AF的吸附量和吸附速率,且吸附动力学符合Langmuir速率方程.

A novel hierarchical porous carbon aerogel (HPCA) was fabricated and its nanostructure was investigated by SEM and N2 adsorption. The methylene blue (MB) adsorption properties of the HPCA in water were studied. It is found that the HPCA has a hierarchical micro-, meso- and macropore structure. Its BET and micropore surface areas are 512 and 359 m2·g-1, respectively. The MB adsorption capacity increases with adsorption time, speed of stirring, temperature and pH value, and the MB removal efficiency can reach 99.8% under optimized conditions. The adsorption kinetics can be well described by a pseudo-second-order equation and the adsorption is controlled by liquid film diffusion in the initial stages and intraparticle diffusion later.