To allow for the use of graphene in various nanoelectronic applications, the methods for the large-scale production of graphene with controllable electrical properties need to be developed. Here, we report the results of a fundamental study on the remarkable conversion between n- and p-type reduced graphene oxide (rGO) with changes in the thermal annealing temperature. It was found that the charge carriers in rGO for temperatures of 300–450 °C and 800–1000 °C are electrons (n-type), whereas for temperatures of 450–800 °C, they are holes (p-type). This is because the individual oxygen functional groups present on rGO are determined by the annealing temperature. We found that the predominance of electron-withdrawing groups (i.e., carboxyl, carbonyl, and sp3-bonded hydroxyl, ether, and epoxide groups) resulted in p-type rGO, while that of electron-donating groups (sp2-bonded hydroxyl, ether and epoxide groups) lead to n-type rGO. In addition, as a proof of concept, a flexible thermoelectric device consisting of GO-700 and GO-1000 as p-type and n-type components, respectively, was fabricated. This device, which contained eight pairs of the two components, exhibited an output voltage of 4.1 mV and an output power of 41 nW for ΔT = 80 K. These results demonstrate that the carrier characteristics of rGO can be altered significantly by changing the functional groups present on it, thus allowing it to be used in various applications including flexible thermoelectrics.

As commercial interest in flexible power-conversion devices increases, the demand is growing for high-performance alternatives to brittle inorganic thermoelectric materials. As an alternative, we propose a flexible single-walled carbon nanotube (SWCNT)-doped tellurium nanowire (TeNW) hybrid film and, for the first time, rationally engineer the work function of the SWCNTs to effectively filter charge carriers in an energy-dependent manner at the interfaces between the carbon and the inorganic semiconductor. The acid treatment used to control the SWCNT work function allows the interfacial barrier between the SWCNT and the TeNW to be raised and lowered. While the hybrid film with a large barrier of 0.82 eV has a low power factor due to poor carrier transfer, the power factor (3.40 μW·m⁻¹·K⁻²) in the film with a lower barrier of 0.23 eV is several times higher than that of either pure TeNW or hybrid film with 0.82 eV due to effective energy filtering effect. The transport characteristics of the hybrid film are explored to quantitatively elucidate the carrier filtering at the SWCNT-TeNW interfaces. These demonstrate the effectiveness of optimizing SWCNT work functions to improve the thermoelectric properties of SWCNT/TeNW hybrid films, thus indicating that this strategy can be applied to flexible/or wearable thermoelectrics.

Continuous efforts have been made to attain high performance Li-S batteries by preventing loss of soluble polysulfides, whereas issues related to insoluble discharge products, Li₂S₂ and Li₂S, have been underestimated. In this paper, we demonstrate that facile and mild method, diazotization, enables uniform functionalization on the surface of ordered mesoporous carbon (CMK-3) with aniline functional groups while it does not deteriorate the original CMK-3 microstructure. The aniline groups possess favorable interactions with insoluble discharge products. Thus, they homogeneously distribute the insoluble discharge products during cycling. The proposed materials exhibit outstanding electrochemical properties with regards to stability (920 mAh g^-1 at 0.2 C after 100 cycles) and rate capability (814 mAh g^-1 at 1 C) when evaluated as a cathode material for lithium sulfur batteries.

Length of multi-walled carbon nanotube (MWCNT) has strong impact on mechanical strength of MWCNT/polymer composite. In this paper, MWCNT/polyamide 6, 6 (PA 66) composites using ten different MWCNTs were prepared by melt processing. The harsh mixing process used to achieve a fine dispersion of MWCNTs in the polymer matrix broke and severely reduced the lengths of the MWCNTs. The characteristics of MWCNTs that influence the breakage and length reduction were systematically and experimentally explored. Insights into designing the microstructures and morphological properties of pristine MWCNTs were provided, based on the correlation data and statistical evaluation results, in an effort to preserve the high aspect ratio of the MWCNTs during the melt mixing process, thereby expecting the enhanced mechanical properties of the composite.

In this work, we examined the reasons underlying the humidity-induced morphological changes of electrospun fibers and suggest a method of controlling the electrospun fiber morphology under high humidity conditions. We fabricated OPV devices composed of electrospun fibers, and the performance of the OPV devices depends significantly on the fiber morphology. The evaporation rate of a solvent at various relative humidity was measured to investigate the effects of the relative humidity during electrospinning process. The beaded nanofibers morphology of electrospun fibers was originated due to slow solvent evaporation rate under high humidity conditions. To increase the evaporation rate under high humidity conditions, warm air was applied to the electrospinning system. The beads that would have formed on the electrospun fibers were completely avoided, and the power conversion efficiencies of OPV devices fabricated under high humidity conditions could be restored. These results highlight the simplicity and effectiveness of the proposed method for improving the reproducibility of electrospun nanofibers and performances of devices consisting of the electrospun nanofibers, regardless of the relative humidity.

In this research, we have analyzed the electrochemical characteristics of the different rGO/Co3O4 composites prepared by controlling the rGO surface characteristics and its relationship between the growth of Co3O4 nanoparticles and the performance of the pseudocapacitor. Reduced graphene oxide/cobalt oxide (rGO/Co3O4) nanocomposites of different morphologies were prepared through the simple hydrothermal method. First, different kinds of graphite precursors, crumpled and planar with different properties, were used to determine the most suitable substrate to grow Co3O4 nanoparticles. As a result, rGO/Co3O4composite synthesized from planar graphite shows a higher specific capacitance of 207.2, 170.1, and 141.5 Fg−1 at 1, 2, and 5 Ag−1 than the one prepared from crumpled graphite. In the second part, planar graphite, confirmed to be the most suitable substrate from the previous part, was oxidized under various oxidation conditions to increase the oxygen functional groups attached on the GO surfaces and observed to see how it affects the growth of Co3O4 nanoparticles and its influence on the electrochemical performance of the rGO/Co3O4 pseudocapacitor. As a result, the one with the largest amount of functional groups had the Co3O4 nanoparticles well dispersed and grown on the rGO substrate in small nanoparticle sizes, as small as 5.9 nm, leading to an improved electrochemical performance. Thus, the specific capacitance with the least amount of oxygen functional groups are 207.2, 170.1, and 141.5 Fg−1 and for the largest amount of functional groups are 411.5, 371.4, and 292.7 Fg−1, at 1, 2, and 5 Ag−1 respectively. This approach could become a guideline for the ideal fabrication of rGO/metal oxide composite for further research involving rGO based pseudocapacitors.

A controlled assembly and alignment of carbon nanotubes (CNTs) in a high-packing density with a scalable way remains challenging. This paper focuses on the preparation of self-assembled and well-aligned CNTs with a densely packed nanostructure in the form of buckypaper via a simple filtration method. The CNT suspension concentration is strongly reflected in the alignment and assembly behavior of CNT buckypaper. We further demonstrated that the horizontally aligned CNT domain gradually increases in size when increasing the deposited CNT quantity. The resultant aligned buckypaper exhibited notably enhanced packing density, strength, modulus, and hardness compared to previously reported buckypapers.

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Current theranostic approaches in cancer therapy demand delivery systems that can carry multiple drugs or imaging agents in a single nanoplatform with uniform biodistribution and improved target specificity. In this study, we have developed amphiphilized poly(ethyleneimine) nanoparticles (aPEI NPs) as a versatile multi-cargo delivery platform. The aPEI NPs were engineered to have the loading capacity for both hydrophobic molecules and negatively charged hydrophilic colloidal cargos through amphiphilic modification, i.e., octadecylation and subsequent PEGylation of poly(ethyleneimine). In aqueous phase, the resulting aPEIs underwent amphiphilic self-assembly into spherical nanoparticles whose structure is constituted of the hydrophobic core with the positively charged surface and the hydrophilic neutral corona. The high degree of PEGylation resulted in the tiny colloidal size (<15 nm in diameter) and rendered the outmost surface coated with an antifouling corona which minimizes general shortcomings of poly(ethyleneimine)-based nanocarriers (e.g., cytotoxicity and liver filtration) while keeping its advantage (loading capability for negatively charged drugs). The unique nanostructure of aPEI NPs allowed for facile loading of hydrophobic model drugs (rubrene and IR780) in the core as well as negatively charged colloids (Pdots, proteins and DNA) on the inner surface via the hydrophobic and electrostatic interactions, respectively. Fluorescence imaging experiments demonstrated that the highly PEGylated aPEI-25 NPs showed prolonged blood circulation with minimal liver filtration and efficient delivery of the loaded cargos to the tumor. These combined merits, along with negligible toxicity profiles both in vitro and in vivo, validate the potential of aPEI-25 NPs as a versatile nanocarrier for multi-cargo delivery.

Thermoelectrics is a challenging issue for future energy harvesting and cooling technology. We here have demonstrated a new system of the tellurium nanowire (TeNW) films hybridized with single-walled carbon nanotube (SWCNT) as a flexible thermoelectric material and investigated their thermoelectric properties as a function of SWCNT weight ratio in the hybrid. The excellent mechanical stability and electrical conductivity of SWCNT enhance the flexibility and thermoelectric properties of the pure TeNW film. The addition of 2 wt% SWCNT into TeNW matrix significantly increases the electrical conductivity from 4 to 50 S m⁻¹ while maintaining the high thermopower, thereby leading to one order of magnitude higher figure of merit (ZT) compared to the pure TeNW film. These results indicate that the SWCNT/TeNW hybrid film would be promising for a potential use as a flexible thermoelectric material.

Graphene oxide (GO) was recently reported to assemble into one-dimensional fiber precursors that can be used to produce next-generation multifunctional graphene-based materials. This study describes the facile fabrication of GO fibers with excellent mechanical properties, utilizing a diamine cross-linker that forms ion bridges between the GO layers. Organic co-coagulants and post-drawing processes, which are usually employed in typical GO spinning processes, were not used here. The GO layers readily aligned along the spinning axis, and the GO formed closely packed structures in the fibers. The fibers displayed a Young’s modulus of 26.6 GPa and a tensile strength of 384.3 MPa in maximum. The interlayer microstructure of the GO sheets could be tuned by modifying the structures of the cross-linking diamine groups, yielding a range of mechanical properties. These observations suggested that our newly developed GO fiber synthesis method could enable applications of graphene-based fibrous materials through GO surface chemistry modification approaches.

Reduced graphene oxide-based films were prepared to assess their effects as gas barriers on the stability of organic photovoltaic (OPV) devices. The direct spin-casting of a graphene oxide suspension onto an aluminum electrode was performed to encapsulate the associated OPV device with a reduced graphene oxide film. The lifetime of the OPV device after the reduction process was found to be increased by a factor of 50. The gas barrier properties of a graphene oxide layer are closely related to its surface roughness and dispersibility. Furthermore, these gas barrier properties can be enhanced by controlling the thermal reduction conditions. The thermal reduction of a graphene oxide film at a low heating rate results in a low water vapor permeability, only 0.1% of that of an as-prepared polyethylene naphthalate film. These results indicate that the dispersibility, surface roughness, and reduction conditions of a graphene oxide film significantly influence its gas barrier performance. Further investigations of the reduction of graphene oxide films are expected to enable further improvements in performance.

A bulk tungsten tile with conventional and shaped castellation structures was exposed to various plasmas in KSTAR during 2012 campaign, in order to verify the functions of the shaped castellation designed for ITER divertor. The thermal response of the tile during the campaign was measured by thermocouples. The tungsten tile was collected after the campaign and the castellation structures were examined. The deposition inside the gap was studied to identify the contributions of ions and charge exchange neutrals. The shaped castellation shows smaller penetration depth of ions by a factor of ~1/2 than that of conventional one, thus less deposition inside the gap which is consistent with the prediction made by SPICE2 code. It seems that blister formation and cracking have occurred during plasma shots.

The Hansen solubility parameters (HSPs) of as-produced multi-walled carbon nanotubes (APMWCNTs) were determined by means of inverse gas chromatography (IGC) technique. Due to non-homogeneous surfaces of the APMWCNTs arising from defects and impurities, it was necessary to establish adequate working conditions for determining the HSPs of the CNTs. We then obtained the HSPs of the APMWCNTs and compared these results with earlier reports as determined by using sedimentation and molecular dynamics simulation methods. It was found that the determination of the HSPs of the CNTs by IGC can give enhanced determination range based on the adsorption thermodynamic parameters, compared to the HSPs determined using sedimentation methods. And the HSPs of the APMWCNTs, determined here, provided good guidelines for the selection of feasible solvents that can improve the dispersion of the APMWCNTs.

Thermal degradation of titanium–containing metal-organic frameworks (MOFs; MIL-125 and MIL-125-NH₂ at 350 °C for 6 h in air produced TiO₂ nanoparticles of ca. 10 nm in diameter. Scanning electron and transmission electron microscope analyses indicated that those nanoparticles were aggregated randomly within each crystalline particle of their MOF precursors. The TiO₂ nanoparticles prepared from MIL-125-NH₂ exhibited higher activity for the degradation of 4-chlorophenol under visible light.

The chirality and diameter are found to simultaneously affect the solubility of SWCNTs. The solubility parameter of armchair SWCNTs is greater than that of zigzag SWCNTs, for a given diameter and length, except for very small diameters. The lower structural stability of the armchair SWCNTs leads to smaller molar volumes. Thus, the chirality of SWCNTs alters the structural stability and consequently the solubility parameter of the SWCNTs.

We discuss the theoretical approaches for various electrochemical capacitor systems via performance-potential estimation in regard to specific energy and power densities. Typical energy storage systems, such as symmetric capacitor system and asymmetric capacitor system, are classified with the symmetry of the electrodes (symmetric/asymmetric), and the types of electrolytes (aqueous/organic). Energy and power densities of each system are theoretically calculated using various factors and coefficients for performance comparison. Then, theoretical modeling for the BatCap system is conducted to indicate the electrochemical performance of this new concept device followed by consideration of ideal structure of the BatCap electrode material. Conclusively, this study successively indicates the performance of each energy storage system depending on the specified conditions of the electrodes and electrolyte which consist of the energy storage systems.

Exceptional progress has been made with chemical vapor deposition (CVD) of graphene in the past few years. Not only has good monolayer growth of graphene been achieved, but large-area synthesis of graphene sheets has been successful too. However, the polycrystalline nature of CVD graphene is hampering further progress as graphene property degrades due to presence of grain boundaries. This review will cover factors that affect nucleation of graphene and how other scientists sought to obtain large graphene domains. In addition, the limitation of the current research trend will be touched upon as well.

A methyl-modified metal-organic framework (m-TiBDC) shows significantly enhanced hydrostability than unmodified TiBDC, and thus can maintain almost intact CO₂ gas adsorption capacity even after its immersion in water for 2 h while TiBDC does not.

We report a template-free and easy solvent evaporation method during carbonizing a metal-organic framework (MOF) for the construction of large-scale meso- and macropore. While the direct thermal evaporation method of non-volatile solvent captured in micropore of a MOF is believed to reduce overall porosity of the resultant MOF, this method unprecedentedly directs the reorganization of MOFs toward the production of ultrahigh porous carbon materials. The obtained porous carbon materials possess a unique interconnected three-dimensional wormhole-like structure, high specific surface area (3000 m² g^-1), and exceptionally high pore volume (5.45 cm³ g^-1). The micropores, along with accessible meso- and macropores, provide ion storage site and ion transport channel, respectively, that contributes to a rapid elimination of large amounts of salt within a very short period of time.

A strategy for fabricating organic photovoltaic (OPV) devices based on PCDTBT nanofibers and PC70BM is described. Electrospinning techniques are used to prepare PCDTBT nanofibers and OPV devices in ambient air. The diameters of the PCDTBT nanofibers are approximately twice the exciton diffusion length, 20 nm. The active layer exhibits 100% photoluminescence quenching due to the small nanofiber diameter, indicating that the excitons are efficiently dissociated. The electrospun PCDTBT nanofibers absorb more photons at longer wavelengths, leading to improved photon harvesting. OPV devices composed of the PCDTBT nanofibers show a high short circuit current of 11.54 mA/cm² and a high power conversion efficiency of 5.82%. The increase in the short circuit current is attributed to enhanced photon harvesting and charge transport. This method may be applied to the fabrication, in ambient air, of large-area active layers composed of other new conjugated polymers to yield high-performance OPV devices.

Sulfur-carbon nanosheet hybrids (SCNHs) are simply synthesized by a single-step solid solvothermal reaction as the cathode material for lithium sulfur (LiS) batteries. Sulfur is homogeneously embedded into the carbon nanosheet by in-situ hybridization process, which enhances the electron and ion transportation due to the higher electronic conductivity and morphology, respectively. The solid solvothermal reaction provides insight into the unique chemical-state of sulfur content in the sulfur-carbon hybrids by small difference in electronegativity between sulfur and carbon contents. This characteristic effect on the production of electrolyte-dissoluble lithium sulfide in the electrochemical reaction can enhance the cycle performance of the hybrid as a cathode material in LiS batteries. The SCNHs show improved electrochemical performance of 810 mAh g^-1 at 100 mA g^-1 and excellent Coulombic efficiency close to 100 % at a high rate.

We report on thermopower (TEP) and resistance measurements of inhomogeneous graphene grown by chemical vapor deposition (CVD). Unlike the conventional resistance of pristine graphene, the gate-dependent TEP shows a large electron-hole asymmetry. This can be accounted for by inhomogeneity of the CVD-graphene where individual graphene regions contribute with different TEPs. At the high magnetic field and low temperature, the TEP has large fluctuations near the Dirac point associated with the disorder in the CVD-graphene. TEP measurements reveal additional characteristics of CVD-graphene, which are difficult to obtain from the measurement of resistance alone.

Photovoltaic devices based on nanocomposites composed of conjugated polymers and inorganic nanocrystals show promise for the fabrication of low-cost third-generation thin film photovoltaics. In theory, hybrid solar cells can combine the advantages of the two classes of materials to potentially provide high power conversion efficiencies of up to 10%; however, certain limitations on the current within a hybrid solar cell must be overcome. Current limitations arise from incompatibilities among the various intradevice interfaces and the uncontrolled aggregation of nanocrystals during the step in which the nanocrystals are mixed into the polymer matrix. Both effects can lead to charge transfer and transport inefficiencies. This article highlights potential strategies for resolving these obstacles and presents an outlook on the future directions of this field.

Quantum Hall effect (QHE) is clearly seen in graphene grown by chemical vapour deposition (CVD) using platinum catalyst. The QHE is even observed in samples which are irregularly decorated with disordered multilayer graphene patches and have very low mobility (< 500 cm²V^‐1s^‐1). The effect does not seem to depend on electronic mobility and uniformity of the resulting material making it promising for metrological applications.

Interest in two-dimensional, sheet-like or flake-like carbon forms has expanded beyond monolayer graphene to include related materials with significant variations in layer number, lateral dimension, rotational faulting, and chemical modification. Describing this family of “graphene materials” has been causing confusion in the Carbon journal and in the scientific literature as a whole. The international editorial team for Carbon believes that the time has come for a discussion on a rational naming system for two-dimensional carbon forms. We propose here a first nomenclature for two-dimensional carbons that could guide authors toward a more precise description of their subject materials, and could allow the field to move forward with a higher degree of common understanding.

In this work, we report the preparation of reduced graphene oxide (rGO)-based freestanding recyclable oil adsorbent via an environmentally friendly one-step low-temperature thermal reduction process. The heating rate was adjusted to successfully control the macroporosity of the rGO fims (rGOFs), thereby modulating the adsorption behaviors. The adsorption capacities for a variety of organic solvents and oil species, measured as the percentage weight gain, were measured. Adsorption capacities up to 4500% of the initial rGOF weight were achieved. The films displayed excellent stability over 10 cycles of use and regeneration without incurring significant structural damage or a decrease in the oil adsorption properties. These results suggested that the rGOF-based oil adsorbents may potentially be useful as next-generation oil adsorbent materials for the remediation of maritime ecosystem in the wake of a massive oil spill.

We report synthesis, optical/structural characterization of new fluorescent rod-coil amphiphiles based on the PEGylated -cyanostilbene skeleton (12EO-CNMBE and 12EO-CNTFMBE) and their self-assembly behaviors in water. Distinct from the common amphiphilic behavior of nonfluorinated 12EO-CNMBE forming spherical nanostructures, fluorinated 12EO-CNTFMBE has proven to be the first example of a molecular building block that can self-assemble in water into small-dimension, small-aspect-ratio organic nanorods with aggregation-induced enhanced emission (AIEE). The robust structural integrity and hydrophobic/π-conjugated nature of the fluorinated block assembly, as well as the anti-fouling coating by the hydrophilic PEG block, enabled stable encapsulation of a model drug (Nile Red) within the self-assembled nanorod structure and its successful delivery through membrane filters. By virtue of these advantageous attributes along with high intracellular uptake efficiency, the 12EO-CNTFMBE nanorods manifested potential as a self-signaling fluorescent nanocarrier for the intracellular delivery of hydrophobic cargos.

Hydrogen bonding is a major intermolecular interaction for self-assembly occurring in nature. Here we report novel polymeric carbohydrates, i.e., poly(oxyethylene galactaramide)s (PEGAs), as biomimetic building blocks to construct hydrogen bond-mediated self-assembled nanoparticles that are useful for biomedical in vivo applications. PEGAs were conceptually designed as a biocompatible hybrid between polysaccharide and poly(ethylene glycol) (PEG) to attain multivalent hydrogen bonding as well as fully hydrophilic, non-ionic and antifouling characteristics. It was revealed that PEGAs are capable of homospecies hydrogen bonding in water and constructing multi-chain assembled nanoparticles whose structural integrity is highly stable with varying concentration, temperature and pH. Using near-infrared fluorescence imaging we demonstrate facile blood circulation and efficient tumor accumulation of the self-assembled PEGA nanoparticles that were intravenously injected into mice. These in vivo behaviors elucidate the combined merits of our design strategy, i.e., biocompatible chemical constitution capable of multivalent hydrogen bonding, antifouling properties, minimal cell interaction and mesoscopic colloidal self-assembly, as well as size-motivated tumor targeting.

Photodynamic therapy (PDT) is a non-invasive treatment modality for selective destruction of cancer and other diseases and involves the colocalization of light, oxygen, and a photosensitizer (PS) to achieve photocytotoxicity. Although this therapeutic method has considerably improved the quality of life and life expectancy of cancer patients, further advances in selectivity and therapeutic efficacy are required to overcome numerous side effects related to classical PDT. The application of nanoscale photosensitizers (NPSs) comprising molecular PSs and nanocarriers with or without other biological/photophysical functions is a promising approach for improving PDT. In this review, we focus on four nanomedical approaches for advanced PDT: (1) nanocarriers for targeted delivery of PS, (2) introduction of active targeting moieties for disease-specific PDT, (3) stimulus-responsive NPSs for selective PDT, and (4) photophysical improvements in NPS for enhanced PDT efficacy.

Stainless steel coupons with cavity structure were installed at different poloidal locations in KSTAR during 2009 campaign to study deposition and H/D retention inside the gap of PFCs. The deposition profiles at different poloidal locations indicate that the incoming species have high surface loss probability (β) and they are probably charge exchange neutral particles. The (H+D)/C ratios of layers inside the coupons were in a range from 0.04 to 0.37 at different poloidal locations which might be caused by different contribution of different hydrocarbon species. Campaign integrated, time averaged net C, H/D atom flux density towards outer walls are in the similar range with other carbon dominated machines.

Hierarchically porous carbon-coated ZnO quantum dots (QDs) (3.5 nm) were synthesized by a one-step controlled pyrolysis of the metal–organic framework IRMOF-1. We have demonstrated a scalable and facile synthesis of carbon-coated ZnO QDs without agglomeration by structural reorganization. This unique microstructure exhibits outstanding electrochemical performance (capacity, cyclability, and rate capability) when evaluated as an anode material for lithium ion batteries.

Carbon nanotube (CNT) dispersions have been prepared using a variety of surface modification methods; however, these methods frequently have a negative effect on the intrinsic properties of CNTs or need to remove the surface modifiers. The Flory-Huggins theory suggests that such problems can be alleviated or eliminated, if ideally, when the solubility parameters of CNTs and a given medium are very similar or equal to each other. Since the earlier reported solubility parameters of CNTs were determined by indirect methods and varied in wide ranges, we suggested herein a possible way of directly determining the solubility parameter of various types of CNTs by using a finite-length model, and reported the determined solubility parameters of pristine single-walled carbon nanotubes (SWCNTs) and pristine double-walled carbon nanotubes (DWCNTs). Through the validity test of the suggested model it was found that the 2 nm finite-length of CNT can represent the longer CNTs for the study of the solubility parameters. In addition, the pristine DWCNTs were found to have higher solubility parameters than do the pristine SWCNTs, and within the given type of CNTs the solubility parameters varied inversely with the diameter of the CNTs. Based on the obtained result it was expected that the solubility parameters for pristine multi-walled carbon nanotubes (MWCNTs) should be similar to or slightly higher than the values for DWCNTs.

Due to an error that was undetected during the final production process, the starting sentence of the first paragraph on page 51 of the article should read: “ sH-PS-b-f-PI as an acid form was derived from a PS b-PI precursor, which was synthesized by anionic polymerization. ” The publisher sincerely apologizes for any inconvenience that may have been caused by this error.

We studied the relationship between the thermal conditions and the evolution of the porosity in thermally reduced graphite oxide (TH-rGO) and found that the heating rate, rather than reduction temperature and atmospheric condition, played a crucial role in the evolution of porosity during the thermal reduction of GO at low temperatures. Higher heating rates increased the porosity of the TH-rGO. A slow heating rate facilitated the evolution of H2O and CO2 whereas a higher heating rate released CO2 and CO gases with the concurrent development of a folded and crumpled morphology. We further demonstrated that the higher heating rate resulted in a highly porous texture with lower reduction temperature (below 140 °C) and shorter reduction time (less than 5 min), indicating that the reduction time and temperature are found to be dependent on the heating rate.

The battery–supercapacitor hybrid electrode, consisting of both faradaic rechargeable battery components and non-faradaic rechargeable supercapacitor components in a single electrode, is successfully developed using Li4Ti5O12–activated carbon (LTO–AC) hybrid nanotubes in a negative electrode for an advanced energy storage device. Li4Ti5O12 and PVA-derived activated carbon are hybridized with morphological control over the one-dimensional (1D) tubular structures via an in situ sol–gel reaction combined with electrospinning, followed by a hydrothermal reaction and appropriate heat treatment. The prepared LTO–AC hybrid nanotubes are tested at a variety of charge–discharge rates as anode materials for use in lithium-ion rechargeable batteries that deliver a specific capacity in the range of 128–84 mA h g−1 over a 100–4000 mA g−1 charge–discharge rate in the potential range 1.0–2.5 V vs. Li/Li+. The hybridized LTO–AC hybrid nanotubes electrode is included in a new type of hybrid energy storage cell, denoted as BatCap, as the negative electrode using commercialized activated carbon (AC) as the positive electrode. The hybrid BatCap cell exhibits a high energy density of 32 W h kg−1 and a high power density of 6000 W kg−1, comparable to the properties of a typical AC symmetric capacitor.

The catalytic activity of Pt nanoparticles (NPs) significantly influences the electrochemical performance of direct methanol fuel cells. Information about the factors that influence the electrochemical activity of the catalyst themselves is scarce; hence, guidelines for the preparation of Pt NPs that yields the best performances are lacking. With consideration for this situation, we systematically investigated the relationship(s) between the characteristics of Pt NPs and their electrochemical performance. The general characteristics of Pt NPs, such as the average size, loading density, and dispersion status on the support, were varied in the presence of poly(acrylic acid)-wrapped multiwalled carbon nanotubes by controlling the preparation conditions, including the pH of the aqueous solution, the reaction temperature, and the reaction time. The enhanced catalytic activity is attributable to higher degree of dispersion, specific surface area, and electrochemically active surface area of Pt NPs. The optimized catalyst exhibits a ∼165% higher catalytic activity toward methanol oxidation than the commercial E-TEK.

A straightforward method for significantly improving the moisture resistance of MOFs is described. In the proposed method, MOFs are subjected to thermal treatment, thus inducing the formation of an amorphous carbon coating on the MOF surfaces that prevents hydrolysis. This approach should open up new practical applications for MOFs in areas hitherto unexplored due to concerns regarding moisture sensitivity.

We report a simple, cost-effective, and environmentally benign process for reducing graphite oxide by treating solely with sulfuric acid. The suggested process consists of a two-step reduction of graphite oxide, first in aqueous sulfuric acid at room temperature and then in concentrated sulfuric acid with refluxing. X-ray diffractometry, X-ray photoelectron spectroscopy, Raman spectroscopy and thermogravimetric analysis demonstrated that the graphite oxide was reduced effectively and was comparable in composition to reduced graphite oxide prepared using previously described methods that rely on toxic and hazardous reducing agents, such as hydrazine, sodium borohydride, or hydrohalic acids.

We report a simple method by which the neutralization point in the Boehm titration can be easily determined without going through a pre-screening process to remove the effect of atmospheric carbon dioxide (CO2). The proposed method is based on the principle that the equivalence and the corresponding neutralization point of the reaction bases remains unchanged regardless of the dissolution of CO2 in the reaction bases. This method was used to measure the surface functionality of acid-treated multi-walled carbon nanotubes with high precision