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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 the 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 versatile nanocarriers for multi-cargo delivery. [ABSTRACT FROM AUTHOR]

Abstract: 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. [Copyright &y& Elsevier]

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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM PUBLISHER]

Carbon/TiO2 composite nanotubes were fabricated via a very simple electrospinning process and their dual functionalities of adsorptivity and photocatalytic activity were evaluated using Rhodamine B (RhB) as a model organic pollutant. A poly(vinyl alcohol) (PVA) aqueous solution was directly electrospun into a coagulation bath containing titanium (IV) tetraisopropoxide (TTIP) solution so that PVA-core/TiO2-shell composite nanofibers were formed through the in situ sol-gel reaction of TTIP. The carbon/TiO2 composite nanotubes were then fabricated by heat treatment of composite nanofibers under nitrogen atmosphere. By using several characterization methods, we confirmed that the resultant nanotubes consisted of anatase TiO2 nanocrystallites embedded in a carbonaceous matrix. The prepared nanotubes exhibited fast adsorption of RhB with high capacity compared with a commercial porous carbon, and they also showed the photocatalytic decomposition activity for the dye molecules under UV irradiation comparable to the degradation by P-25 and ST-01 (commercial TiO2). Finally, the carbon/TiO2 composite nanotubes exhibited several cycle performances of adsorption-photodegradation for RhB. This indicates that the composite nanotubes can adsorb and photodecompose organic pollutants repeatedly without additional activating processes. [ABSTRACT FROM AUTHOR]

Abstract: 1-D carbon nanomaterials were prepared by a novel catalyst-free and template-free synthesis based on the carbonization of in situ formed fibrous polymer precursors. The products had ribbon-like shapes and a mean diameter of ∼40nm. The proposed method is simple, inexpensive, and environmentally friendly, and yields promising candidate materials for applications such as electrostatic dissipation and touch screens. [Copyright &y& Elsevier]

This research was supported by the Fundamental Research Program (PNK7340) of the Korea Institute of Materials Science (KIMS) and a grant from the Korea Institute of Science and Technology Open Research Program. Please find the correct Acknowledgements here: Acknowledgements J.H.P., Y.J.O., and D.Y.P. contributed equally to this work. This work was supported by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP) (Nos. [Extracted from the article]

Abstract: The first principal calculation based on the density functional theory was performed to investigate the hydrogen storage behavior of Li-doped single-walled carbon nanotubes (SWCNTs). It was found that, through Li-doping, two new adsorption sites for hydrogen molecules are created in addition to the inherent three adsorptive sites which are exterior, interior and interstitial regions of pristine SWCNTs: the first site (denoted ‘region 1’) is the nanotube''s sidewall whose electronic distribution status is influenced by the doped Li atoms. The second site (denoted ‘region 2’) exists on the positively charged Li atoms which result from the transfer of electrons from the Li atoms to the SWCNTs. The calculations show that although the adsorption energy in region 1 increases somewhat, the adsorption behavior of hydrogen is marginally different from that of pristine SWCNTs. However, in region 2, at least three hydrogen molecules can be adsorbed by each charged Li-atom, and based on the maximum Langmuir coverage (of 0.55), 1.1 hydrogen molecules can be adsorbed onto each charged Li-atom. When this result is considered together with the effective specific surface area, the hydrogen storage capacities of Li-doped SWCNTs with the doping ratio of LiC15 are approximately 0.1wt% in region 1 and 1.17wt% in region 2 at 10MPa and 300K so that the total H2 storage capability is 1.27wt%, which agrees well with previously reported results. [Copyright &y& Elsevier]

In 1963, the 117 Committee of the Japan Society for the Promotion of Sciences (JSPS) specified standard procedures for the determination of lattice constants and crystallite sizes of carbon materials, especially graphitized materials, the so-called “Gakushin” method. In 2002 the 117 Committee started to discuss the revision of the specification in order to accept some modern computing processes, such as automatic step-scanning measurements of diffraction intensities, profile fitting for diffraction lines, etc. In this paper, the English version of the revised specification is presented to the international community of scientists working on carbon materials, and to solicit comments. [Copyright &y& Elsevier]

A new thermally stable, high strength and high modulus aromatic polyamide film was obtained via the formation of the molecular composite of p-PDCBTA and P-LCl. The two polymers exhibited good miscibility identified with the measurement of dynamic mechanical property and FTIR spectra. By the combination of drawing by 40% and subsequent heat treatment, the tensile property of the composite film could be achieved to the strength of 450 MPa and the modulus of 24 GPa, which were sustainable upto 400 °C. [ABSTRACT FROM AUTHOR]

B Design of New Carbon Nanostructures b In article number 2102718, Jae Ho Kim, Taehoon Kim, Seung Jae Yang, and co-workers demonstrate a new carbon nanostructure consisting of interconnected N-doped graphitic nanocubes embedding nickel nanoparticles. A New Class of Carbon Nanostructures for High-Performance Electro-Magnetic and -Chemical Barriers (Adv. Sci. 22/2021) This study gives new insights into structural design of the carbon nanostructure for high-performance electromagnetic and electrochemical barriers. [Extracted from the article]

Electrochemical capacitors based on RuO2 were prepared onto electrospun TiO2 nanorods. Further heat treatment of the TiO2 at 800 °C under nitrogen was found to greatly improve the electrochemical performance of the RuO2 electrodes, especially at fast charge-discharge rates. The specific capacitance was found to decrease by only 33% when the scan rate increased from 10 to 1000 mV s-1 (from 687 to 460 F g-1). The characteristic response time of the RuO2 electrode was found to be 0.15 s when a heat-treated TiO2 substrate was used, which is 20 times better than that of the pristine TiO2 used. [ABSTRACT FROM AUTHOR]

Lightweight structural materials are commonly used as effective fillers for advanced composites with high toughness. This study focused on enhancing the toughness of direct‐spun carbon nanotube yarns (CNTYs) by controlling the micro‐textural structure using a water‐gap‐based direct spinning. Drawing inspiration from the structural features of natural spider silk fibroin, characterized by an α‐helix in the amorphous region and β‐sheet in the crystalline region, multiscale bundles within CNTYs are reorganized into a unique nano‐coil‐like structure. This nano‐coiled structure facilitated the efficient dissipation of external mechanical loads through densification with the rearrangement of multiscale bundles, improving specific strength and strain. The resulting CNTYs exhibited exceptional mechanical properties with toughness reaching 250 J g−1, making them promising alternatives to commercially available fibers in lightweight, high‐toughness applications. These findings highlight the significance of nano‐coiling engineering for emulating bio‐inspired micro‐textural structures, achieving remarkable enhancement in the toughness of CNTYs. [ABSTRACT FROM AUTHOR]

Developing methods to assemble nanomaterials into macroscopic scaffolds is of critical significance at the current stage of nanotechnology. However, the complications of the fabrication methods impede the widespread usages of newly developed materials even with the superior properties in many cases. Here, we demonstrate the feasibility of a highly-efficient and potentially-continuous fiber-spinning method to produce high-performance carbon nanotube (CNT) fiber (CNTF). The processing time is <1 min from synthesis of CNTs to fabrication of highly densified and aligned CNTFs. CNTFs that are fabricated by the developed spinning method are ultra-lightweight, strong (specific tensile strength = 4.08 ± 0.25 Ntex−1), stiff (specific tensile modulus = 187.5 ± 7.4 Ntex−1), electrically conductive (2,270 S m2kg−1), and highly flexible (knot efficiency = 48 ± 15%), so they are suitable for various high-value fabric-based applications. The tensile strength of a carbon nanotube fiber is predicted to increase as its constituent nanotubes become more perfectly and densely aligned. Here, the authors present an optimized direct-spinning and chlorosulfonic acid densification method to rapidly produce carbon nanotube fibers with excellent mechanical and electrical properties. [ABSTRACT FROM AUTHOR]

Hydrogen energy is promising renewable energy and specifically, hydrogen storage is a bottleneck to commercializing hydrogen energy. Researchers have relied on the synthesis of porous materials in physisorption and lowering the H2 binding energy of hydride materials in chemisorption, all of which have been conducted in a similar manner respectively. However, the development of hydrogen storage materials applicable to onboard system isn't found yet. Hence, we examined the phenomenon of eccentric H 2 storage in carbon nanopores with sub-1 nm diameters reported earlier, finding a lack of deep research on the fundamentals of this phenomenon. We formulate a hypothesis of H 2 storage by intrinsic EMF (IEMF) interaction and firstly discover that in contrast to general intuition, the neutral carbon nanopore forms a significant IEMF even without an external EMF. Moreover, we confirm the difference of IEMF inside the nanopore from that outside the nanopore due to the overlap between the graphene layers and demonstrate that the resultant IEMF inside the nanopore governs the H2 storage in the carbon nanopore. This result will shed light on all the other areas related to abnormal phenomena in nanopores with sub-1 nm diameters. [Display omitted] [ABSTRACT FROM AUTHOR]

Energy storage materials for energy storage system or electric vehicle should be able to supply high capacity quickly. Especially, Li-ion accessibility within graphite-based anodes is the key point to enhance mass transfer and the electrochemical performance. In terms of solvated Li-ion accessibility to the space, space in graphite-based anode is classified as two consecutive scales, channel and surface pores. A Li-ion transferrable channel is controlled by the calendering process, and surface pores are modified with a chemical vapor deposition surface coating to enhance the solvated Li-ion accessibility in each space. Cross-analysis of BET with small-angle X-ray scattering was conducted to determine whether each space is accessible and where the optimal point is. Finding correlations with the tortuosity value provided not only quantitative but also geometrical information on the space which was derived from the making process of each electrode, reflecting actual solvated Li-ion movement. This study not only suggests two distinguishable views in enhancing the accessibility of solvated Li-ions but also presents new insights to figure out how the changes in space characteristics affect the electrochemical performance. Furthermore, these findings could provide a potential strategy to estimate commercialized graphite such that the actual solvated Li-ion movement can be interpreted. [Display omitted] [ABSTRACT FROM AUTHOR]

Super strong fibers, such as carbon or aramid fibers, have long been used as effective fillers for advanced composites. In this study, the highest tensile strength of 5.5 N tex−1 for carbon nanotube yarns (CNTYs) is achieved by controlling the micro‐textural structure through a facile and eco‐friendly bundle engineering process in direct spinning without any post‐treatment. Inspired by the strengthening mechanism of the hierarchical fibrillary structure of natural cellulose fiber, this study develops multiscale bundle structures in CNTYs whereby secondary bundles, ≈200 nm in thickness, evolve from the assembly of elementary bundles, 30 nm in thickness, without any damage, which is a basic load‐bearing element in CNTY. The excellent mechanical performance of these CNTYs makes them promising substitutes for the benchmark, lightweight, and super strong commercial fibers used for energy‐saving structural materials. These findings address how the tensile strength of CNTY can be improved without additional post‐treatment in the spinning process if the development of the aforementioned secondary bundles and the corresponding orientations are properly engineered. [ABSTRACT FROM AUTHOR]

Continuous efforts have been devoted to establishing viable synthetic guidelines for dimension-controlled carbon nanomaterials. This paper proposes a dimension-convertible synthetic procedure based on metal-organic complexes. One- or two-dimensional carbon nanostructures can be developed through the different graphitization behaviors of metal-organic complexes according to the selected metal ions. These nanostructures possess vital functions from surface nitrogen functionalities and embedded metal species for a wide range of applications. These distinctive structural functions are applied to functionalize the general separator as an electrochemical barrier for lithium–sulfur (Li–S) batteries. Benefiting from the polysulfide blocking function and electrocatalytic effect, the resulting separator Li–S cells exhibit high-rate capability and stable cycling performance. The remarkable performance combined with comprehensive characterization of the resulting dimension-controlled carbon nanomaterials provides new insights into the design of functional nanomaterials for energy and environmental research. [Display omitted] [ABSTRACT FROM AUTHOR]

Flexible thermoelectrics that enable conformal contact with heat sources of arbitrary shape are indispensable for self‐powered wearable electronics. Scalable integration of flexible thermoelectric (TE) materials into functional devices has improved over the past few years, however, the practical applications of flexible TE materials are still hindered by low performance. Herein, highly aligned carbon‐nanotube yarns (CNTYs) are proposed, combined with selective doping via picoliter scale inkjet printing. Coagulation assisted by van der Waals forces ensures a highly aligned structure of the CNTY, thus achieving the ultrahigh power factors of 4091 and 4739 µW m−1 K−2 for the p‐ and n‐type, respectively. The proposed TE materials can be effortlessly up‐scaled into highly integrated modules via inkjet printing. A highly integrated, flexible CNTY‐based TE generator (TEG) with 600 PN pairs generates unparalleled milliwatt‐scale power at ΔT = 25 K, which is a few orders of magnitude higher than those of previously reported flexible material‐based TEGs. This TEG successfully powers a red light‐emitting diode using body heat alone, requiring no external power sources. For the seamless operation of practical applications requiring high power, this work explores the key design parameters for flexible TEGs with high performance and manufacturability and presents new platforms for self‐powered wearable electronics. [ABSTRACT FROM AUTHOR]

The realization of the exceptional intrinsic properties of carbon nanotubes (CNTs) remains a significant challenge in the field of CNT yarns and films. A fundamental lack of understanding regarding how the bundle dimensions determines the properties and how to control these bundles has resulted in insufficient performances of CNT-based components. Recognizing the absence of systematic guidelines for preparing high-performance CNT yarns or films, our focus has been on investigating the driving forces behind multidimensional CNT bundles to uncover structure-property correlations based on the dimension. We have revisited the state-of-the-art progress in engineering methods for microstructure to provide insights on achieving the desired microstructure. The interdependencies between electrical and mechanical properties, as well as the agglomeration and alignment behavior of both nanoscale and microscale bundles, emphasize the importance of selecting between dried-state engineering and swollen-state engineering of bundles within CNT yarns or films depending on their dimensions. On the basis of consideration and discussions on the advanced technologies and theoretical approaches, we have proposed possible routes to further enhance the properties of CNT yarns and films. • Systematic guidelines of fabricating high-performance CNT yarn or films are addressed. • The driving forces behind the formation and determination of CNT bundles based on dimension are highlighted. • The correlation between dimension of CNT bundles and properties of CNT yarn or film is discussed. • Tailor-fit engineering methods for CNT bundles according to dimension are reviewed. [ABSTRACT FROM AUTHOR]

Abstract: A series of structurally isomeric water-soluble azo naphthalene dyes were synthesized, and their thermal properties were examined by thermogravimetric analysis and differential scanning calorimetry. Dye-based color filters were also fabricated using the synthesized dyes. Transmittance (98.9%) at 650 nm and a wide color gamut (62.8%) were achieved using one of the color filters. All the prepared dyes had a degradation temperature above 280 °C, which varied with the dye structure. The degradation temperatures of the dyes were presumed to be related to the intra- and inter-molecular interactions of the structural isomers. From quantum mechanics calculations, their intra-molecular interactions were similar. However, the degradation temperatures generally increased in proportion to their density. According to the molecular mechanics calculations, the different structures induced changes in electrostatic attraction, steric hindrance and linearity of the dyes, which in turn caused changes in their molecular packing geometry, density and degradation temperature. [ABSTRACT FROM AUTHOR]

Li–O 2 batteries have attracted great attention because of their high theoretical energy density, which exceeds the highest possible value of currently used Li-ion batteries. The operation of Li–O 2 batteries include the formation and decomposition of Li 2 O 2 at the cathode, and cell degradation occurs because such discharge products accumulate on the pores and cause pore clogging. For reversible charge–discharge process, in this study, a biaxially multilayered high crystalline carbon nanotube (CNT) web was designed and fabricated by a modified direct spinning method, which was the first demonstration that realize the biaxially multilayered structure in one-step process. The high crystallinity of the CNT surface reduced its decomposition and the biaxial alignment of CNT enabled the web to be opened for O 2 gas and electrolytes without pore clogging. The pore size distribution verified that effective pores were better developed in the biaxially multilayered CNT web, which facilitated the flow of O 2 gas and electrolytes. The use of this specially designed CNT as a cathode improved the cyclability by 75% and dramatically reduced the overpotential. For the practical use of Li–O 2 batteries, a 3D folded cell with biaxially multilayered CNT web electrode is fabricated and demonstrated 30 cycles at 100 W h/kg cell cutoff. [Display omitted] [ABSTRACT FROM AUTHOR]

The desire for multivariable applications has encouraged extensive study to exploit multi-functional carbon materials owing to their superior physicochemical properties, wide availability, and massive productivity. In particular, the design of a porous architecture is the key to manipulating their function, thereby promoting the practicality. This paper suggests a simple and scalable synthetic process to prepare mesostructured porous carbon derived by pseudo metal-organic coordination. Inspired by metal-organic framework synthesis, the zinc ion is selected to function as both a mesostructure inducer and self-vanishing porogen, thereby enabling the direct carbonization of non-carbonizable precursors without complicated and environmental burden steps. The resulting porous carbon materials possess mesostructured morphologies, resembling diverse metal oxide crystals with distinct pore architectures, which can be tailored for various applications. Furthermore, the functionalities of the resulting mesostructured porous carbon are demonstrated by evaluating the adsorption behavior for large molecules and the electrochemical performance of the sulfur cathode for Li–S batteries. Image 1 [ABSTRACT FROM AUTHOR]