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Controllable nitrogen doping is an effective way to regulate the electronic properties of graphene and further to facilitate its wider application. However, the synthesis of high-quality nitrogen-doped graphene (NG) with a controllable nitrogen configuration still faces considerable challenges. In this work, we present for the first time a simple method for the one-step synthesis of NG with ionic liquids (ILs) as precursors, which avoids the defects introduced by secondary doping and simplifies the process. Using 1-Ethyl-3-methylimidazolium dicyanamide (EMIM-dca) as the precursor, we obtained a high-quality NG with few defects (I

Silicon oxides (SiOx, 0x2) has been considered as one of the most promising candidate materials for high specific energy anode materials and attracted extensive attention. However, there are still some shortcomings within SiOx that extremely limit its promotion in industry, especially the large volume expansion and poor conductivity. Reasonable design of silicon oxides (SiOx) electrode material is very important to improve its energy storage performance. Here, we fabricated a novel porous SiOx/C nanohybrids based on the facile sol-gel method followed by pyrolysis, in which carbon and SiOx not only exhibited uniform distribution at the nanoscale, the stability of SiOx/C network can also be easily adjusted via controlling the hydrolysis and condensation rate of precursors in situ. Thanks to the excellent electrical conductivity and structural stability of carbon, uniform distribution of SiOx and carbon at the nanoscale, as well as the porous structure. The SiOx/C(50) electrode, with the most appropriate carbon content, delivered a high lithium storage capacity and excellent cyclability. Specifically, a reversible capacity of 808 mA h g

SiOx is an attractive anode material for lithium-ion batteries due to its considerable capacity. However, its obvious volume expansion and low conductivity result in poor electrochemical performance. Herein, a novel single-phase nanotube structure with uniform distribution of nanoscale SiOx units and amorphous carbon matrix was fabricated. The hollow nanotube and homogeneously distributed ultrafine SiOx units greatly alleviate volume changes. The amorphous carbon facilitates electron transport throughout the network and offers a buffer to further reduce the volume expansion of SiOx. Benefiting from this unique structure, as-prepared single-phase SiOx/C NTs demonstrate excellent durability and rate capability. Specifically, it delivers a high reversible specific capacity (713 mAh g

In this study, we reported a facile two-step reduction method to prepare a high-quality graphene with intact structure. Hydroxyl group is acquired by utilizing LiAlH4 to reduce the oxygen-containing functional groups in GO. Then it is further reduced by ethanethiol/aluminum trichloride (Et-SH/AlCl3) to obtain graphene. The results of Infrared and XPS showed that the prepared graphene material (rGO2) has been reduced completely and had structural integrity. Besides, the conductivity of rGO2 obtained can reach 2.632 * 103 S m−1, which is higher than that obtained by general chemical reduction method and high temperature reduction method. Investigated as a potential material for supercapacitors, the as-prepared graphene reveals excellent electrochemical properties, including good rate capability and cycling stability, which mainly benefits from its intact structural characteristics.

In this study, the crystalline and homogenous ZnTiO3 particles were first synthesized in KCl-NaCl eutectic chloride salts at 700–850 °C. Then the ZnTiO3 was successfully loaded onto g-C3N4 sheets to form ZnTiO3/g-C3N4 composites during the polymerization of melamine. Compared with pure g-C3N4, ZnTiO3/g-C3N4 composites have shown an obvious red shift phenomenon and enhanced light harvesting ability in the spectra range of 200–800 nm as well as much lower recombination rate of the photogenerated charge carriers. The ZTOCN1-800 samples exhibited a 1.69 times specific surface area as pure g-C3N4 by BET analysis, and a 76% degradation efficiency for methyl orange (MO) under visible light irradiation in 180 min, about 13 times as that of pure ZnTiO3 and 3 times as that of pure g-C3N4. Moreover, The ZTOCN1-800 samples achieved complete degradation of MB and RhB under visible light irradiation within 90 min. This is attributed to the intimate heterostructure interface between g-C3N4 and ZnTiO3 due to ZnTiO3 particles intercalation into the g-C3N4 sheets, which reduced the self-aggregation of the g-C3N4 sheets and greatly facilitated the charge transfer from photo-excited g-C3N4 to ZnTiO3. These were demonstrated by XRD, SEM, EDX, TEM, UV–Vis, PL and photoelectrochemical analysis.

In this work, zero-dimensional (0D)/ two-dimensional (2D) TiO2/g-C3N4 composite photocatalysts with homogeneous well-developed heterostructures were successfully prepared from LiCl-KCl flux using a facile molten salt assisted in-situ route. The phase composition, morphology, surface area, chemical structure, thermal stability as well as optical property of the heterostructured composites were systematically characterized. Benefiting from the exfoliation effect of molten salt flux, the flux-grown g-C3N4 products exhibit a rough surface with porous structures and many co-existed secondary products including nanosheets, nanrods and nanotubes, which also lead to an obvious increase in the surface area of the flux-grown g-C3N4 and composites. The photocatalytic performance of the TiO2/g-C3N4 heterostructure composites was evaluated by photodegradation of methyl orange (MO) and rhodamine B (RhB) under the visible light irradiation (λ > 420 nm), and proved to be greatly improved compared to individual TiO2 and g-C3N4. Moreover, the enhanced photocatalytic activity of TiO2/g-C3N4 composites can be attributed to the higher surface area and the synergistic effects between TiO2 and g-C3N4 including the increased light harvesting ability and more efficient separation of the photogenerated charge carriers, which originates from the construction of TiO2/g-C3N4 heterostructures at the interface between the two components. Furthermore, a possible mechanism responsible for the enhanced photocatalytic performance was also proposed. Additionally, the TiO2/g-C3N4 composites showed a superior adsorption ability for the removal of cationic dye methylene blue (MB) from aqueous solutions, due to their high surface area and strong electrostatic interactions between catalysts and dye molecules.

Three-dimensional sponge-like reduced graphene oxide/silicon/carbon nanotube composites were synthesized by one-step hydrothermal self-assembly using silicon nanoparticles, graphene oxide and amino modified carbon nanotubes to develop high-performance anode materials of lithium ion batteries. Scanning electron microscopy and transmission electron microscopy images show the structure of composites that Silicon nanoparticles are coated with reduced graphene oxide while amino modified carbon nanotubes wrap around the reduced graphene oxide in the composites. When applied to lithium ion battery, these composites exhibit high initial specific capacity of 2552 mA h/g at a current density of 0.05 A/g. In addition, reduced graphene oxide/silicon/carbon nanotube composites also have better cycle stability than bare Silicon nanoparticles electrode with the specific capacity of 1215 mA h/g after 100 cycles. The three-dimension sponge-like structure not only ensures the electrical conductivity but also buffers the huge volume change, which has broad potential application in the field of battery.

We proposed a large-sized graphene preparation method by short-circuit discharge of the lithium-graphite primary battery for the first time. LiCx is obtained through lithium ions intercalation into graphite cathode in the above primary battery. Graphene was acquired by chemical reaction between LiCx and stripper agents with dispersion under sonication conditions. The gained graphene is characterized by Raman spectrum, X-ray diffraction (XRD), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), Atomic force microscope (AFM) and Scanning electron microscopy (SEM). The results indicate that the as-prepared graphene has a large size and few defects, and it is monolayer or less than three layers. The quality of graphene is significant improved compared to the reported electrochemical methods. The yield of graphene can reach 8.76% when the ratio of the H2O and NMP is 3:7. This method provides a potential solution for the recycling of waste lithium ion batteries.

Polyethylene oxide (PEO)-based solid polymer electrolytes (SPEs) are appealing solid electrolytes for lithium-metal batteries (LMBs) due to their high safety, low cost and flexibility. However, PEO'snarrow electro-chemical potential window and poor interfacial compatibility with the electrode restrict PEO-based SPE development. Herein, we used a solution-casting method to prepare PEO-based SPE membranes reinforced with an organic ionic plastic crystal—N,N-diethylpyrrolidinium bis(fluorosulfonyl)amide (C2epyrFSI). The as-prepared SPE exhibits high ionic conductivity of 3.02 × 10−4 S cm−1 at 50 °C, an extremely wide electro-chemical window (5.1 V) and flexible mechanical properties. Using SPE, the Li symmetric cells can cycle for 2000 h at a current density of 0.1 mA cm−2 without short circuiting at 50 °C. Furthermore, the Li|SPE|LiFePO4 all-solid-state LMBs have a high initial discharge specific capacity of 157.3 mAh g−1 at 0.2C and a capacity retention rate of 96% after 120 cycles. This study shows that the PEO-C2epyrFSI SPE is a promising electrolyte for all-solid-state LMBs.

In this work, boron and nitrogen co-doped hierarchical porous carbon (BN-HPC) with a relatively high contents of boron (3.97 wt%) and nitrogen (12.10 wt%) is synthesized by a method combined with template process and carbonization of hierarchical porous resin using melamine and boric acid as nitrogen and boron sources, respectively. The co-doping method achieves a high boron doping level (8 times of that of single boron doped sample) which is of great significance in increasing the doping efficiency of boron. The hierarchical porosity, structure and surface chemical properties are studied in detail via various means, such as Transmission Electron Microscopy, N 2 sorption, X-ray diffraction, X-ray photoelectron spectroscopy and elemental analysis, etc. Owing to the synergistic effect of hierarchical porosity and heteroatoms doping, BN-HPC exhibits greatly improved electrochemical capacitive performance of 304 F g −1 at a current density of 0.1 A g −1 and good rate capability (189 F g −1 remained at a current density of 10 A g −1 ). The strategy of synthesis is facile and very effective.

Two-dimensional (2D) graphitic-C3N4 (g-C3N4) was successfully hybridized with one-dimensional (1D) flux-grown Na-modified K2Ti6O13 nanobelts (Na-K2Ti6O13 NBs) for the first time to construct novel 1D/2D Na-K2Ti6O13/g-C3N4 heterostructured photocatalysts using a facile mixing–calcination method. The heterostructured Na-K2Ti6O13/g-C3N4 composites with three-dimensional (3D) hybrid architectures exhibited a remarkably enhanced photocatalytic efficiency for organic pollutant degradation in comparison with pure Na-K2Ti6O13 and g-C3N4 under both simulated sunlight and visible-light irradiation (λ > 420 nm), which could be mainly attributed to the synergistic effects between Na-K2Ti6O13 and g-C3N4 including more efficient interfacial charge transfer, longer lifetimes and the stronger oxidation and reduction ability of photogenerated charge carriers, fundamentally originating from the formation of Na-K2Ti6O13/g-C3N4 heterojunctions based on the well-matched energy-band structures. Moreover, the Na-K2Ti6O13/g-C3N4 hybrids showed good stability and reusability for the photocatalytic degradation of organic pollutants. Finally, the possible mechanisms responsible for the improved simulated sunlight and visible-light photocatalytic performance were also investigated, respectively, based on the results of PL spectra, time-resolved fluorescence decay spectra, radical species trapping experiments, ESR spectra and PL-TA measurements. Overall, this work will not only be beneficial for the design and development of more efficient visible-light-responsive g-C3N4-based composites for solar energy conversion and environmental remediation but will also be influential in optimizing the visible-light photocatalytic activity of wide-band-gap 1D titanate nanomaterials to meet the requirements of practical applications.

Microspherical polyaniline/graphene (PANI/G-MS) composites are synthesized using sheet-like polyaniline/graphene oxide (PANI/GO) composites as raw materials via spray-drying and chemical reduction process, in which the granulated polyaniline (PANI) is in-situ grown on the surface of graphene oxide. For PANI/G-MS composites, PANI uniformly coats on the surface of graphene which can constitute a high conductive network to accelerate electronic transmission in the composites electrode for supercapacitors. Moreover, PANI/G-MS composites form numerous channels among their spherical particles during random stacking of sheet-like PANI/GO composites via spray-drying process. Due to the special structure, the electrochemical capacitance of the as-synthesized PANI/G-MS composite reaches 596.2 and 447.5 F g −1 at a current density of 0.5 and 20 A g −1 , respectively, indicating superior rate capability. Additionally, after 1500 cycles at a current density of 2 A g −1 , 83.7% of the initial capacitance is retained.

In this paper, nitrogen/phosphorous co-doped porous carbons (N/P-PCs) with hierarchical porosity were prepared by a one-step carbonization method, of which nitrogen-containing PAA/MMF is the precursor and phosphorous-containing sodium hypophosphite monohydrate is the novel pore-forming agent. The synergistic effect of multilevel porosity and heteroatomic functionalities results in good electrochemical performance. Tested as electrode materials for supercapacitors, N/P-PC-50 demonstrates a maximal specific capacitance of 177 F g−1 at a current density of 0.1 A g−1, excellent rate capability (67% capacitance retention at 10 A g−1) and superior cycling stability (no capacitance loss after 10000 cycles). In addition, N/P-PCs have the potential to be used for other applications, and this facile, low-cost and safe synthesis strategy provides a feasible route to develop many hierarchically porous carbon-based materials.

A series of nitrogen doped porous carbons are prepared using a simple and economic template carbonization method, in which nano-CaCO3 and ethylenediamine (EDA) and carbon tetrachloride (CTC) serve as a template and nitrogen-containing carbon precursors, respectively. The textural parameters of all the obtained carbon materials are tunable. The porosity and nitrogen content of the nitrogen doped porous carbons strongly depend on the dosage of nano-CaCO3. When the ratio of CaCO3 to the sum weight of EDA and CTC increases from 0.2 to 0.4, the specific surface area increases from 783.72 to 2535.09 m2 g−1, meanwhile the nitrogen content decreases from 16.13 to 9.47 wt%. While when the ratio of CaCO3 to the sum weight of EDA and CTC is moderate, the as-prepared nitrogen doped porous carbons (NPC-0.3) contains as high as 13.45 wt% of nitrogen has a balanced specific surface areas of 1276.14 m2 g−1, exhibits the largest specific capacitance of 226 F g−1 at a current density of 0.1 A g−1 in 1 M H2SO4 aqueous electrolyte, due to the co-contribution of double layer capacitance and pseudo-capacitance. Additionally, it shows excellent rate capability (capacitance retention ratio of 58.4% at a current density of 30 A g−1) and good cycling stability (no capacitance decay over 10 000 charge-discharge cycles), making it a promising electrode material for supercapacitors.

In this work, composite membranes consisting of triethylmethylammonium bis(fluorosulfonyl)imide (N1222FSI), poly(ethylene oxide) (PEO) and lithium bis(fluorosulfonyl) imide (LiFSI) have been produced as solid polymer electrolytes (SPEs). The composite SPEs provide good mechanical property, high ionic conductivity at 50 °C, high electrochemical and thermal stability as well as superior interfacial compatibility with lithium metal. Moreover, Li/LiFePO4 cells containing the best-performing SPE exhibit high discharge capacity and excellent cycling performance. The results show that the novel composite SPEs might be promising electrolytes applied in all-solid-state lithium batteries.

Nitrogen-doped porous carbon materials (NPCs) were successfully obtained through one-step carbonization of an ionic liquid, that is, 1-ethyl-3-methylimidazolium dicyanamide (EMIM-dca), adopting eutectic salt (ZnCl2-NaCl) as the porogen agent. The nitrogen content and textural structure of the obtained carbon materials are highly dependent on the dosage of salt. The as-prepared NPCs integrate the superiorities of reasonable pore structure, high nitrogen content as well as homogeneous distribution, and high surface area. When served as electrodes for supercapacitor, a typical NPC-2 electrode exhibits a high specific capacitance of 335.3 and 206 F g−1 at current densities of 0.5 and 10 A g−1, respectively, considerable energy density (up to 10.1 Wh kg−1), and excellent cycling stability with almost no degradation over 10,000 cycles in KOH aqueous solution.

Improving the electrochemical performance of manganese dioxide (MnO 2 ) electrodes is of great significance for supercapacitors. In this study, a novel honeycomb MnO 2 nanospheres/carbon nanoparticles/graphene composites has been fabricated through freeze-drying method. The honeycomb MnO 2 nanospheres are well inserted and dispersed on the graphene. Carbon nanoparticles in the composites act as spacers to effectively prevent graphene from restacking and agglomeration, construct efficient 3D conducting architecture with graphene for honeycomb MnO 2 nanospheres, and alleviate the aggregation of honeycomb MnO 2 nanospheres by separating them from each other. As a result, such honeycomb MnO 2 nanospheres/carbon nanoparticles/graphene composites display much improved electrochemical capacitive performance of 255 F g −1 at a current density of 0.5 A g −1 , outstanding rate capability (150 F g −1 remained at a current density of 20 A g −1 ) and good cycling stability (83% of the initial capacitance retained after 1000 charge/discharge cycles). The strategy for the synthesis of these composites is very effective.

A porous carbon microsphere with moderate specific surface area and superior specific capacitance for supercapacitors is fabricated from polyphosphazene microsphere as the single heteroatoms source by the carbonization and subsequent KOH activation under N2 atmosphere. With KOH activation, X-ray photoelectron spectroscopy analysis confirms that the phosphorus of polyphosphazene microsphere totally vanishes, and the doping content of nitrogen and its population of various functionalities on porous carbon microsphere surface are tuned. Compared with non-porous carbon microsphere, the texture property of the resultant porous carbon microsphere subjected to KOH activation has been remarkably developed with the specific surface area growing from 315 to 1341 m(2) g(-1)and the pore volume turning from 0.17 to 0.69 cm(3) g(-1). Prepared with the KOH/non-porous carbon microsphere weight ratio at 1.0, the porous carbon microsphere with moderate specific surface area of 568 m(2) g(-1), exhibits intriguing electrochemical behavior in 1 M H2SO4 aqueous electrolyte, with superior specific capacitance (278 F g(-1) at 0.1 A g(-1)), good rate capability (147 F g(-1) remained at 10 A g(-1)) and robust cycling durability (No capacitance loss after 5000 cycles). The promising electrochemical performance could be ascribed to the synergy of nitrogen heteroatom functionalities and the porous morphology.

Hierarchically porous carbon with micropores, mesopores, macropores and high specific surface area for supercapacitors is fabricated from an aqueous curable composition by curing and subsequent carbonization, followed by KOH activation under N 2 atmosphere. With the manipulation of KOH activation to the peculiar morphology developed during carbonization, the external specific surface area grows from 208 to 1151 m 2 g −1 , while the specific surface area of micropores stays at around 1100 m 2 g −1 , leading to the micro/external specific surface area ratio decreases from 5.36 to 0.94. Prepared with KOH/carbon weight ratio at 2.0, the porous carbon with total specific surface area of 1590 m 2 g −1 and moderate micro/external specific surface area ratio of about 2.0, exhibits intriguing electrochemical performance in 1 M H 2 SO 4 aqueous electrolyte, such as superior specific capacitance (274 F g −1 at 0.1 A g −1 ), excellent rate capability (161 F g −1 remained at 20 A g −1 ) and outstanding cycling stability (no capacitance loss over 5000 cycles). The promising electrochemical performance could be attributed to the synergy of the hierarchically porous morphology and high specific surface area.

A rich nitrogen-doped porous carbon with high specific surface area and superior specific capacitance for supercapacitors is synthesized from poly(acrylic acid)/methylated melamine-formaldehyde resin through sol-gel process at ambient temperature for 24 hrs, followed by calcination and carbonization at 350 °C and 500 °C for 1 hour respectively and KOH activation at 700 °C for 2 hours under N2 atmosphere. The porosity and surface chemistry of the rich nitrogen-doped porous carbon are swiftly manipulated by KOH activation, with the specific surface area increasing from 14.2 to 2674 m2 g−1 and nitrogen content varying from 20.3 to 8.8 by wt.%, respectively. The porous morphology and nitrogen functionalities enable the nitrogen-doped porous carbon to perform an intriguing electrochemical performance in 1 M H2SO4 aqueous electrolyte, such as a superior specific capacitance at the current density of 0.2 A g−1 (280 F g−1), excellent rate capability (171 F g−1 remained at 10 A g−1) and outstanding cycling durability (no capacity decay after 9000 cycles), which make it a promising electrode material for high performance supercapacitors.

Nitrogen-doped ordered mesoporous phenolic resin-based carbon (N-OMC) with a high nitrogen content (11.64 wt.%) and 2D hexagonal mesostructure is synthesized by the carbonization of 2D hexagonal ordered mesoporous phenolic resin with melamine as the nitrogen source. The effect of nitrogen doping on structure and porosity, and the doping configuration of nitrogen are investigated in detail. Compared with the 2D hexagonal ordered mesoporous phenolic resin-based carbon (OMC) without nitrogen doping, N-OMC shows superior capacitive performance in 1 M H2SO4 electrolyte. The specific capacitance of N-OMC is up to 216 F g−1 at a current density of 0.1 A g−1, attributed to the co-contribution of double-layer capacitance and pseudocapacitance, which is much higher than that (127 F g−1) of OMC. Moreover, N-OMC shows a good rate capability (114 F g−1 retained at a high current density of 20 A g−1) and an excellent cycling stability (no capacitance loss over 10 000 cycles). The good electrochemical performance of N-OMC is ascribed to the nitrogen doping and the ordered mesostructure, and makes it a promising electrode material for supercapacitors.

A series of hierarchical activated mesoporous carbons (AMCs) were prepared by the activation of highly ordered, body-centered cubic mesoporous phenolic-resin-based carbon with KOH. The effect of the KOH/carbon-weight ratio on the textural properties and capacitive performance of the AMCs was investigated in detail. An AMC prepared with a KOH/carbon-weight ratio of 6:1 possessed the largest specific surface area (1118 m(2) g(-1)), with retention of the ordered mesoporous structure, and exhibited the highest specific capacitance of 260 F g(-1) at a current density of 0.1 A g(-1) in 1 M H2 SO4 aqueous electrolyte. This material also showed excellent rate capability (163 F g(-1) retained at 20 A g(-1)) and good long-term electrochemical stability. This superior capacitive performance could be attributed to a large specific surface area and an optimized micro-mesopore structure, which not only increased the effective specific surface area for charge storage but also provided a favorable pathway for efficient ion transport.

A series of nitrogen-doped porous carbons are prepared through KOH activation of a nonporous nitrogen-enriched carbon which is synthesized by pyrolysis of the polymerized ethylenediamine and carbon tetrachloride. The porosity and nitrogen content of the nitrogen-doped porous carbons depend strongly on the weight ratio of KOH/carbon. As the weight ratio of KOH/carbon increases from 0.5 to 2, the specific surface area increases from 521 to 1913 m2 g−1, while the nitrogen content decreases from 10.8 to 1.1 wt.%. The nitrogen-doped porous carbon prepared with a moderate KOH/carbon weight ratio of 1, which possesses a balanced specific surface area (1463 m2 g−1) and nitrogen content (3.3 wt.%), exhibits the largest specific capacitance of 363 F g−1 at a current density of 0.1 A g−1 in 1 M H2SO4 aqueous electrolyte, attributed to the co-contribution of double-layer capacitance and pseudocapacitance. Moreover, it shows excellent rate capability (182 F g−1 remained at 20 A g−1) and good cycling stability (97% capacitance retention over 5000 cycles), making it a promising electrode material for supercapacitors.

Organic materials have been promising materials for “greener and sustainable” lithium-ion batteries due to lightweight, low cost, flexibility, alternative molecular engineering. Six kinds of aromatic imides with different aromatic and aliphatic diamines based on 3,3′,4,4′-benzophenonetetracarboxylic dianhydride (BTDA) were designed, synthesized and studied as anode materials in rechargeable lithium-ion batteries in this work. Compared with ortho-substituted and meta-substituted phenylenediamine, aromatic imide synthesized by p-phenylenediamine shows excellent electrochemical performance on account of its well-organized structure, which possesses 558 mA h g−1 of discharge capacity after 50 cycles at the current density of 25 mA g−1. Besides, imides with shorter alkyl chain would help improve the proportion of electrochemical active conjugated carbonyl compounds, leading to higher capacity. Thus, imide-based electrode materials can be designed efficiently by symmetrical and straight chain structure and less inactive part to gain optimum molecular structure, making it a promising alternative anode material for rechargeable lithium-ion batteries.

A novel phenol–formaldehyde carbon with ordered/disordered bimodal mesoporous structure is synthesized by the facile evaporation induced self-assembly strategy under a basic aqueous condition with SiO2 particles as template. The prepared bimodal mesoporous carbons (BMCs) are composed of ordered mesoporous and disordered mesoporous with diameter of about 3.5 nm and 7.0 nm, respectively. They can be employed as supercapacitor electrodes in H2SO4 aqueous electrolyte after the simple acid-treatment. BMC exhibits an exceptional specific capacitance of 344 F g−1 at the current density of 0.1 A g−1, although it has a relatively low surface area of 722 m2 g−1. And the BMC electrode displays an excellent cycling stability over 10,000 cycles.

Highly ordered, body-centered cubic mesoporous phenol–formaldehyde carbon C-FDU-16 is prepared by a facile evaporation induced self-assembly strategy under a basic aqueous condition. Afterwards, in order to increase the active site of surface electrochemical reactions and promote the wettability in aqueous electrolyte, a simple chemical surface modification is carried out on the C-FDU-16 by nitric acid treatment. The C-FDU-16 and the acid-modified C-FDU-16 (N-FDU-16) are used as the active materials for supercapacitors. Although C-FDU-16 has unique 3D mesoporous network combined with high specific surface area, it do not show well supercapacitor properties for its bad wettability with the aqueous electrolyte. However, the N-FDU-16 with acid treatment exhibits the largest specific capacitance of 219 F g−1 at a current density of 0.1 A g−1 in 1 M H2SO4 electrolyte which is 7 times larger than that of the C-FDU-16 and it also shows good cycling stability as well. Therefore, based on the above investigations, ordered mesoporous phenol–formaldehyde carbon such as C-FDU-16 can be a potential candidate for supercapacitors after the simply acid treatment.

A novel anode material for lithium-ion batteries derived from aromatic imides with multicarbonyl group conjugated with aromatic core structure is reported, benzophenolne-3,3',4,4'-tetracarboxylimide oligomer (BTO). It could deliver a reversible capacity of 829 mA h g-1 at 42 mA g-1 for 50 cycles with a stable discharge plateaus ranging from 0.05-0.19 V versus Li+ /Li. At higher rates of 420 and 840 mA g-1 , it can still exhibit excellent cycling stability with a capacity retention of 88% and 72% after 1000 cycles, delivering capacity of 559 and 224 mA h g-1 . In addition, a rational prediction of the maximum amount of lithium intercalation is proposed and explored its possible lithium storage mechanism.

The structure of and synthesis conditions for an organic–inorganic hybrid mesoporous material, HMM-3, containing ethane fragments (–CH 2 CH 2 –) within the pore walls were studied. High resolution transmission electron microscope images and electron diffraction patterns obtained for different crystal axes of HMM-3 indicated that it was of the cubic Pm-3n space group, similar to mesoporous silica SBA-1. Scanning electron micrographs of HMM-3 in different directions confirmed that all of the produced HMM-3 particles had the crystal-like external morphology of a decaoctahedron (18-hedron) with six square {1 0 0} and 12 hexagon {1 1 0} planes with a cubic symmetry. The synthesis conditions for HMM-3 were optimized in a synthesis system comprising 1,2-bis(trimethoxysilyl)ethane (BTME), hexadecyltrimethylammonium chloride (C 16 TMA), sodium hydroxide (NaOH), and water (H 2 O). The highly ordered HMM-3 material was obtained at 95°C with the mixture ratio of BTME:C 16 TMA:NaOH:H 2 O=5.27:4.79:12:1773. The C 16 TMA/BTME ratio and C 16 TMA concentration affected the structural order of the produced mesophase. Only the cubic Pm-3n phase was formed even though the C 16 TMA/BTME ratio and the C 16 TMA concentration were varied with in wide ranges at 95°C.

Crystalline nanoparticles of LiCoO2 are prepared by a sol–gel method at 550 °C and characterized by X-ray diffraction. Their electrochemical behaviors were characterized by cyclic voltammograms, capacity measurement and cycling performance. Results show that the reversible capacity of the nano-LiCoO2 can be up to 143 mAh/g at 1000 mA/g and still be 133 mAh/g at 10,000 mA/g (about 70C) in 0.5 mol/l Li2SO4 aqueous electrolyte. In addition, their cycling behavior is also very satisfactory, no evident capacity fading during the initial 40 cycles. These data present great promise for the application of aqueous rechargeable lithium batteries. Keywords: Aqueous rechargeable lithium battery (ARLB), Nanoparticles, Cathode material, LiCoO2, Large capacity, High rate capability

Novel organic−inorganic hybrid mesoporous materials have been synthesized, in which organic and inorganic oxide moieties are distributed homogeneously at the molecular level in the framework, forming a covalently bonded network. They are highly ordered at the mesoscale, with two- and three-dimensional hexagonal symmetries and well-defined external morphologies. Nitrogen adsorption measurements show a uniform pore-size distribution with pore diameters of 31 and 27 A, and high surface areas of 750 and 1170 m2/g. The synthetic procedure to polymerize the organosilane monomer containing two trialkoxysilyl groups in the presence of surfactant can be applied to the synthesis of a variety of highly ordered organic−inorganic hybrid mesoporous materials.

Hyperbranched poly(amine–ester)s bearing self-complementary quadruple hydrogen bonding units display excellent mechanical and temperature-dependent melt rheological properties, which make them suitable as novel hot-melting materials.

Organosilica porous solids containing chiral organic moieties in the framework with an enantiomeric purity of 95% ee, estimated by eluting organic constituent units from chiral organosilicas, were synthesized from a newly designed chiral (R)-(+)-1,2-bis(trimethoxysilyl)phenylethane precursor via a surfactant-mediated self-assembly approach.

Si is regarded as one of the most promising anode materials for next generation Li-ion batteries, but it usually exhibits poor cycling stability due to the low intrinsic electrical conductivity and huge volume change induced by the alloying reaction with Li. In this study, we present a double protection strategy by fabricating graphene/carbon-coated Si nanoparticle hybrids to improve the electrochemical performance of Si in Li storage. The Si nanoparticles are wrapped between the graphene and the amorphous carbon coating layers in the hybrids. The graphene and the amorphous carbon coating layers work together to effectively suppress the aggregation and destruction of Si nanoparticles, keeping the overall electrode highly conductive and active in Li storage. As a result, the produced graphene/carbon-coated Si nanoparticle hybrids exhibit outstanding reversible capacity for Li storage (902 mAh g(-1) after 100 cycles at 300 mA g(-1)). This work suggests a strategy to improve the electrochemical performance of Li-ion batteries by using graphene as supporting sheets for loading of active materials and carbon as the covering layers.

Surfactant-mediated synthesis strategies are widely used to fabricate ordered mesoporous solids in the form of metal oxides, metals, carbon and hybrid organosilicas. These materials have amorphous pore walls, which could limit their practical utility. In the case of mesoporous metal oxides, efforts to crystallize the framework structure by thermal and hydrothermal treatments have resulted in crystallization of only a fraction of the pore walls. Here we report the surfactant-mediated synthesis of an ordered benzene-silica hybrid material; this material has an hexagonal array of mesopores with a lattice constant of 52.5 A, and crystal-like pore walls that exhibit structural periodicity with a spacing of 7.6 A along the channel direction. The periodic pore surface structure results from alternating hydrophilic and hydrophobic layers, composed of silica and benzene, respectively. We believe that this material is formed as a result of structure-directing interactions between the benzene-silica precursor molecules, and between the precursor molecules and the surfactants. We expect that other organosilicas and organo-metal oxides can be produced in a similar fashion, to yield a range of hierarchically ordered mesoporous solids with molecular-scale pore surface periodicity.

In this report we introduce new types of organic-inorganic hybrid mesoporous materials, in which organic and inorganic moieties are distributed homogeneously at the molecular level in the framework, forming a covalently bonded network. Possessing unique surfaces on which both organic and inorganic components are exposed, these materials are expected to have applications in various areas as catalysts, adsorbents and separators, and as hosts for nano-cluster synthesis. The hybrid mesoporous materials showed not only unique surface properties but also unique structural features in micron- or angstrom-scales. Mesoporous materials containing ethylene groups in the main framework formed a variety of particle morphologies of hexagonal rod, spherical, and decaoctahedral shapes in the sizes of 1-10 μm. Mesoporous material containing phenylene groups showed novel crystal-like 7.6 Å periodicity in the pore walls. The mesoporous material has periodically arranged hydrophobic-hydrophilic surfaces, which is a great advantage for use as catalyst and host material for inclusion chemistry.