Search

This work determines a new set of EUV/x-ray optical constants for aluminum (Al), one of the most important materials in science and technology. Absolute photoabsorption (transmittance) measurements in the 17–1300 eV spectral range were performed on freestanding Al films protected by carbon (C) layers, to prevent oxidation. The dispersive portion of the refractive index was obtained via the Kramers–Kronig transformation. Our data provide significant improvements in accuracy compared to previously tabulated values and reveal fine structure in the Al L1 and L2,3 regions, with photon energy step sizes as small as 0.02 eV. The implications of this work in the successful realization of EUV/x-ray instruments and in the validation of atomic and molecular physics models are also discussed. [ABSTRACT FROM AUTHOR]

Alkylated benzothienobenzothiophenes are an important class of organic semiconductors that exhibit high performance in solution-processed organic field-effect transistors. In this work, we study the near-edge x-ray absorption fine-structure (NEXAFS) spectra of 2,7-didecyl[1]benzothieno[3,2-b][1]benzothiophene (C10-BTBT) at both the carbon and sulfur K-edges. Angle-resolved experiments of thin films are performed to characterize the dichroism associated with molecular orientation. First-principles calculations using the density functional theory-based many-body x-ray absorption spectroscopy (MBXAS) method are also performed to correlate the peaks observed and their dichroism with transitions to specific antibonding molecular orbitals. Interestingly, the dichroism of the dominant, lowest energy peak is opposite at the carbon and sulfur K-edges. While the low-energy peak at the carbon K-edge is assigned to carbon 1s → π* transitions with transition dipole moment (TDM) perpendicular to the planar BTBT core, the dominant low energy peak at the sulfur K-edge is assigned to sulfur 1s → σ* transitions with TDM oriented along the long axis of the BTBT core. These differences at the sulfur and carbon K-edges are understood through the MBAXS simulations that find a reordering of the energy of the lowest energy π* and σ* transitions at the sulfur K-edge due to the strong localization of the σ* orbital over the sulfur atom. This work highlights differences in the NEXAFS spectra of organic semiconductors at carbon and sulfur K-edges and provides new insights into peak assignment and x-ray dichroism relevant for studying the molecular orientation of organic semiconductor films. [ABSTRACT FROM AUTHOR]

Action spectroscopies use a readout created by the action of light on the molecules or material rather than optical absorption. Ultrafast 2D photocurrent and 2D fluorescence spectroscopies are two such action spectroscopies. Despite their utility, multidimensional action spectroscopies suffer from a background created by incoherent population mixing. These backgrounds appear when the action of one molecule impacts that of another, creating a signal that mimics a fourth-order population response but is really just the convolution of two linear responses. The background created by incoherent mixing is often much larger than the desired foreground signals. In this paper, we describe the physical mechanisms that give rise to the incoherent signals, drawing Feynman paths for each. There are three variations of incoherent signals, differing by their pulse ordering. They all have the same phase dependence as the desired fourth-order population signals and so cannot be removed by standard phase cycling, but they do differ in their polarization responses and dephasing times. We propose, and implement, a spectrometer design that eliminates the background signals for isotropically oriented samples, leaving only the desired fourth-order 2D action spectra. Our spectrometer utilizes a TWINS interferometer and a pulse shaper interferometer, each driven with a different white-light source so that the pulse pairs within each interferometer are phase stable, but not between the two. The lack of phase stability between the two interferometers eliminates two of the three incoherent responses. The third incoherent response is eliminated with the polarization scheme ⟨0, π/2, π/4, π/4⟩. Our spectrometer also enables both 2D photocurrent and 2D white-light spectra to be collected simultaneously, thereby enabling a direct comparison between action and optical detection under identical conditions and at the exact same position on the sample. Using this spectrometer and photovoltaic devices made from thin films of semiconducting carbon nanotubes, we demonstrate 2D photocurrent spectra free of incoherent background. [ABSTRACT FROM AUTHOR]

Amorphous carbon nitride (a-CNx) films, prepared by reactive radio frequency magnetron sputtering, exhibit unique characteristics under visible light irradiation, referred to as photoinduced deformation. This phenomenon represents an energy conversion system wherein photon energy transforms into kinetic energy. The chemical bonding structure of a-CNx films was analyzed using near-edge x-ray absorption fine structure (NEXAFS) at the NewSUBARU synchrotron facility of the University of Hyogo, Japan. This analysis aimed to elucidate the mechanisms behind the photoinduced deformation observed in a-CNx films. Three variants of a-CNx films, displaying varying degrees of photoinduced deformation, were deposited using a graphite target and nitrogen gas under different deposition temperatures. The NEXAFS spectra of the a-CNx films with substantial photoinduced deformation showed changes under light irradiation from a Xe lamp (directed through an optical window within the NEXAFS chamber). Specifically, the peaks corresponding to the 1s to π* transition related to C—C and 1s to σ* transition related to C—N bonds exhibited high sensitivity to visible light irradiation. Simultaneously, the N K-edge spectra associated with the 1s to π* transition, attributed to the N—C bond, exhibited a slight intensity decrease. Conversely, the C K-edge spectrum in the a-CNx films displaying minimal photoinduced deformation remained unchanged under visible light irradiation. The N K-edge spectra maintained a consistent shape under both visible light and dark conditions. [ABSTRACT FROM AUTHOR]

[Display omitted] Paper-based relics is an important carrier for recording and preserving information, however, it faces irreversible UV-induced damage, including photocleavage, oxidation, acidification and discoloration, which seriously affects its value and lifespan. Carbon dots (CDs) possess excellent UV absorption and good chemical stability, making them suitable for UV protection. Herein, we propose a high-security and efficient method utilizing CDs films (CDFs) for preventive protection of paper against UV damage. The CDFs with high tunable UV absorbance and minimal absorbance in the visible light range, effectively shield paper from UV radiation while preserving its visual appeal. Moreover, the UV transmittance of the film can be fine-tuned to the content of CDs and can be easily removed from the paper without residue. Artificial accelerated UV aging experiments demonstrate the deceleration of acidification, oxidation, and photocleavage in the protected bamboo paper and Xuan paper. This research paces a new direction for the protection of paper and paper-based relics and artworks with emerging carbon materials, offering customizable protection effects tailored to specific preservation and exhibition requirements. This research pioneers a novel approach to preventive protection of paper and paper-based relics using emerging carbon dots materials, offering tailored protection for diverse preservation needs. [ABSTRACT FROM AUTHOR]

Photocatalytic hydrogen evolution with the use of semiconductors as the light-harvesting units is an attractive route for the clean and renewable energy development. Here, we report interfacial self-assembly of Pd(II)-directed multiporphyrin arrays sensitized oxidized graphitic carbon nitride (O-g-C 3 N 4) nanocomposites and their Langmuir-Blodgett (LB) films. The nanocomposites and LB films can act as both the light-harvesting unit and catalyst for the hydrogen evolution under irradiation. Monolayer behaviors and spectroscopic features indicate that EDTA and polyacrylic acid (PAA) in the subphases can stabilize the monolayer stability and facilitate the LB film deposition, attributed to the hydrogen bonding between EDTA/PAA and tetraaminoporphyrin (TAPP). The multiporphyrin arrays-sensitized O-g-C 3 N 4 @(Pd-TAPP) 3 nanocomposites display improved hydrogen evolution efficiency, because of the expanded light absorption region as well as enhanced separation and transport efficiency of the photoinduced charge carriers. Particularly, when the LB films of O-g-C 3 N 4 @(Pd-TAPP) 3 –EDTA or –PAA are used as the light-harvesting unit and catalyst, the hydrogen evolution rate is about 5–10 times higher than that of the solid powders of similar nanocomposites. Mechanism investigation suggest that EDTA and PAA can not only improve the monolayers and LB films' stability, but also act as the bridged species between the carbon nitride, multiporphyrin arrays and electron donors, hence enhanced charged transfer and hydrogen evolution efficiency. [Display omitted] • Bridged EDTA/PAA molecules stabilize g-C 3 N 4 @(Pd-TAPP) n LB films. • Hydrogen bond and bridged molecules act as electron transport channel. • LB films display 5–10 times higher H 2 evolution rate than the solid powders. • Well-defined 2D arranged Pd(0) catalytic sites enhance H 2 evolution capacity. [ABSTRACT FROM AUTHOR]

[Display omitted] • Surface partially oxidized Re 3 Co 2 @NCF was synthesized via a hydrothermal followed by pyrolysis strategy. • The Re 3 Co 2 @NCF electrocatalyst exhibited outstanding HER performance and stability in alkaline condition. • The partially oxidized surfaces resulting from the electronic interaction between Re and Co led to the enhanced HER activity. Although the theoretical electrocatalytic activity of rhenium (Re) for the hydrogen evolution reaction is comparable to that of platinum, the experimental performance of reported rhenium-based electrocatalysts remains unsatisfactory. Herein, we report a highly efficient and stable electrocatalyst composed of rhenium and cobalt (Co) nanoalloy embedded in nitrogen-doped carbon film (Re 3 Co 2 @NCF). The Re 3 Co 2 @NCF electrocatalyst exhibited remarkable hydrogen evolution performance, with an overpotential as low as 30 ± 3 mV to reach a current density of 10 mA cm−2. In addition, the Re 3 Co 2 @NCF demonstrated exceptional stability over several days at a current density of 150 mA cm−2. Theoretical calculations revealed that alloying cobalt with rhenium altered the electronic structure of the metals, causing partial oxidation of the superficial metal atoms. This modification provided a balance for various intermediates' adsorption and desorption, thereby boosting the intrinsic activity of rhenium for hydrogen evolution reaction. This work improves the electrocatalytic performance of rhenium to its theoretical activity, suggesting a promising future for rhenium-based electrocatalysts. [ABSTRACT FROM AUTHOR]

Purpose: The purpose of this paper is to study the effect of nano polypyrrole-modified boron nitride on the performance of phosphate film. Design/methodology/approach: By adding polypyrrole-modified boron nitride to the phosphate solution, a phosphate film is formed on the metal surface, improving its corrosion resistance. The effect of different concentrations of polypyrrole-modified boron nitride on the corrosion resistance of Q235 carbon steel surface was studied. The corrosion resistance of the phosphate film was evaluated using the copper sulfate drop test. The electrochemical corrosion performance of the phosphate film was assessed using the weak polarization curve method and electrochemical impedance spectroscopy. The surface of the samples was characterized using scanning electron microscopy and X-ray diffraction analysis. Findings: The results show that samples containing polypyrrole-modified boron nitride have a denser and more uniform phosphate film. When the concentration of polypyrrole-modified boron nitride is 0.6 g/L, the drop time of copper sulfate on the formed phosphate film can reach 219 s, which is a 189% increase compared to the performance of the sample without the additive. The current density is 1.06 × 10−6 A/cm2 lower than that of the pure phosphate film, indicating the best corrosion resistance. Polypyrrole-modified boron nitride effectively promotes the formation of the phosphate film. Originality/value: This study used the modification of phosphate solution using nanoparticles to investigate the influence of different nanoparticle concentrations on the phosphate film. The corrosion resistance of the phosphate film was enhanced, providing a method and theoretical guidance for the improvement of phosphate solution formulation. [ABSTRACT FROM AUTHOR]

Activated carbon thin film (ACTF) was prepared via a single-step mixing method through thermal fabrication that was utilized for the removal of phenol in the batch aqueous media. The prepared adsorbent was characterized using TEM, XRD, FTIR, BET, EDX, Raman, and TGA analyses. Batch adsorption experiments were studied by using the effects of different parameters such as pH, temperature, dose, contact time, and initial concentration of phenol solution on adsorption. The maximum phenol removal by ACTF was approximately 89.5% at pH 4, adsorbent dose of 1 g/L, and 50 ppm for the initial concentration of phenol at room temperature through 150 min. Adsorption data were modeled using four adsorption isotherm models (Langmuir, Freundlich, Temkin, and D-R) and three kinetic models (pseudo first order, pseudo second order, and Intraparticle diffusion) using linear and non-linear regression methods. The chi-square (X2) and the correlation coefficient (R2) were both used as error analysis techniques to find the best-fitting equations. The results showed that phenol adsorption on ACTF adsorbent fitted more accurately with nonlinear regression models, which is consistent with Freundlich isotherm and pseudo-second order form. Also, thermodynamic results demonstrated that attachment of phenol onto ACTF adsorbent was spontaneous (negative value of ΔG) and exothermic (negative value of ΔH) with decreasing temperature from 55 °C to 25 °C. Synthesized ACTF showed good regeneration capacity with 0.1 M NaOH as the eluent, making it an appropriate adsorbent for the elimination of phenol. This study evidenced the efficacy of ACTF as a phenol adsorbent. [ABSTRACT FROM AUTHOR]

Van der Waals materials and devices incorporating them exhibit highly thickness‐dependent properties. The small lateral dimensions of mechanically exfoliated 2D‐layered flakes, however, remarkably complicate their precise thickness determination. Quantitative analysis of reflectance measurements using optical microspectroscopy is proven to be as precise as spectroscopic ellipsometry while providing an easily adaptable and non‐destructive method for thickness determination. The use of magnifying objective lenses allows obtaining the reflectance within a measurement spot of only a few microns in diameter. When the dimensions of exfoliated flakes are even smaller, however, the acquired reflectance is a superposition of those of the material of interest and the subjacent materials. To overcome this limitation, a facile approach to reduce the resolvable structure size by combining the evaluation of the reflectance measurement via transfer matrix method with spatial information extracted from optical micrographs is introduced. The efficacy when characterizing micrometer‐sized flakes is exemplarily demonstrated for thickness determination of highly oriented pyrolytic graphite and a thin film of silicon dioxide. It is shown that a maximum error of less than 10% is achieved even when the flake only covers 20% of the measurement spot. [ABSTRACT FROM AUTHOR]

A new galvanic cell design of a self‐powered and 3D‐printable soft sensor showing health monitoring, object recognition, and contactless hand gesture recognition, is reported. The soft sensor consists of a 3D‐printed poly(acrylic acid) (PAA) hydrogel electrolyte layer, a soft anode layer, and a soft cathode layer. The anode layer is a 3D‐printed and Cu2+ cross‐linked poly(N,N‐dimethylacrylamide‐co‐3‐alanine‐2‐hydroxypropylmethacrylate) (PDA) hydrogel dispersed with Cu metal particles (PDA/Cu2+/Cu hydrogel), while the cathode layer is a bottom thin layer of the PAA hydrogel containing MnO2 (PAA/MnO2). Using graphite films as the soft electrodes, the soft sensor is finally assembled. The soft sensor has high force and temperature sensitivities. It gives different electric current responses under stretching, bending, pressing, and impact loading. The soft sensor is demonstrated to be useful in detecting human motion and physiological activities, e.g., breath. Based on the force and contactless temperature sensitivities, the soft sensor is used to recognize human hand gestures and plastic balls with different diameters. This 3D printable soft sensor with self‐powering, contactless motion capturing, and multi‐pimulus sensing capabilities illustrates a new pathway to make soft sensory devices for healthcare and human‐machine interaction applications. [ABSTRACT FROM AUTHOR]

This paper utilizes the reaction of phytic acid (PA) and urea (UM) in polyvinyl alcohol (PVA) solution to synthesize flame retardant gasses (CO2, NH3) for the preparation of PVA composite films containing flame retardant microbubbles. The flame retardancy of PVA composite films was assessed using methods including limiting oxygen index (LOI), vertical burning (UL 94), and cone calorimetry. The results indicated an increase in the LOI of the PVA composite film containing flame retardant microfoam from 20% to 30% compared with the pure PVA film, and that UL 94 reached VTM‐0. Furthermore, its peak exothermic rate and total exothermic amount were reduced by 36.25% and 38.92%, respectively, compared with the pure PVA film. The investigation of the flame‐retardant mechanism employed thermogravimetric‐infrared (TG‐IR), scanning electron microscopy (SEM), Raman spectroscopy, and infrared spectroscopy. The results demonstrate that the CO2 and NH3 flame retardant microbubbles within the composite film render it less ignitable at the initial stage, and that the internal UM of the composite film continues to decompose, releasing CO2 and NH3 upon heating. In addition, the acidic substances decomposed by PA during combustion promote the dehydration, cross‐linking, and cyclization of PVA, generating chemical structures such as POC, POP, and PO4 with enhanced thermal stability. This encourages the formation of a continuous, dense charcoal layer and impedes the transfer of oxygen and heat into the interior. [ABSTRACT FROM AUTHOR]

Featured Application: The IR pulsed laser ablation of different carbon targets using a Nd:YAG laser is investigated. The produced carbon plasma is characterized in terms of maximum ion energy at a laser intensity of about 3 × 109 W/cm2. The presented study can be applied to the use of carbon ions for their successive acceleration in laser ion sources or for the investigation of carbon-nucleation-generating nanoparticles. This work aimed to understand how the energy released by short laser pulses can produce different effects in carbon targets with different allotropic states. The IR pulse laser ablation, operating at 1064 nm wavelength, 3 ns pulse duration, and 100 mJ pulse energy, has been used to irradiate different types of carbon targets in a high vacuum. Graphite, highly oriented pyrolytic graphite, glassy carbon, active carbon, and vegetable carbon have exhibited different mass densities and have been laser irradiated. Time-of-flight (TOF) measurements have permitted the evince of the maximum carbon ion acceleration in the generated plasma (of about 200 eV per charge state) and the maximum yield emission (96 μg/pulse in the case of vegetal carbon) along the direction normal to the irradiated surface. The ion energy analyzer measured the carbon charge states (four) and their energy distributions. Further plasma investigations have been performed using a fast CCD camera image and surface profiles of the generated craters to calculate the angular emission and the ablation yield for each type of target. The effects as a function of the target carbon density and binding energy have been highlighted. Possible applications for the generation of thin films and carbon nanoparticles are discussed. [ABSTRACT FROM AUTHOR]

The integration and portable development of electronic devices urgently require flexible films with high thermal conductivity and insulation to overcome heat accumulation. The layered heterojunction composite films are prepared by the stacking technique for the first time. The morphology, structure composition and thermal stability of heterojunction films are studied. Compared with pure epoxy resin (EP), the heterojunction film still has good thermal stability at 600°C. At the same time, the plane heat conduction network constructed by the expanded graphite (EG) plane of the heterojunction film enables the film to dissipate heat effectively. In the simulation process of actual heat dissipation, the chip surface temperature can be reduced by 10°C. The thermal conductivity of the heterojunction film is 2.49 Wm−1 K−1 when the mass fraction of boron nitride‐ γ aminopropyl triethoxysilane (BN‐KH550) is 50 wt%. Compared with pure epoxy resin, the thermal conductivity is increased by 1464%. The boron nitride (BN) surface resistance of the heterojunction film is large, which can isolate the conductive path of the EG layer and provide effective electrical insulation. [ABSTRACT FROM AUTHOR]

Nanoscale redox‐active molecular films are promising candidates for next‐generation energy storage applications due to their ability to facilitate long‐range charge transport. However, establishing stable and efficient electrode‐molecule interfaces remains a critical challenge. In this study, the properties of redox‐active copper‐polypyridyl thin films covalently bonded to graphite rods are explored, investigating their potential as supercapacitors. Using an electrochemical grafting method, robust covalent interfaces are created, resulting in copper‐polypyridyl films prepared on graphite rods and indium tin oxide (ITO) electrodes, exhibiting both Cu(II) and Cu(I) redox states. These redox‐active mettalo‐oligomeric films demonstrate a structural transition between octahedral and tetrahedral geometries around the Cu(II), and Cu(I), respectively contributing to their charge storage capabilities. The combination of an electrical double‐layer capacitance and pseudocapacitance through Faradaic charge transfer is evaluated in different acidic electrolytes, showing significant capacitance enhancement. Notably, proton‐coupled electron transfer (PCET) at free pyridine‐N sites in Cu(I) polypyridyl complex is identified as a key factor in their distinct behavior in aqueous solutions, a finding supported by computational studies. This study shows the potential of binder‐free thin films for efficient supercapacitor applications, with a maximum areal capacitance of 6.8 mF cm⁻2 in aqueous media, representing an 1840% improvement over bare graphite rods. [ABSTRACT FROM AUTHOR]

Highlights With the wide application of modern electronic devices, the problem of electromagnetic pollution is becoming more and more serious, and the demand for efficient electromagnetic shielding materials is becoming more and more urgent. To address this problem, we homogeneously mixed polyacrylonitrile (PAN), polyvinylpyrrolidone (PVP), and triiron tetraoxide (Fe3O4) nanoparticles by solution blending, and prepared composite precursor membranes by taking advantage of the magnetic properties and good electromagnetic loss characteristics of Fe3O4, as well as the high thermal stability and film‐forming properties of PAN and PVP. Subsequently, carbonized PAN‐PVP/ Fe3O4 composite films with different Fe3O4 contents were successfully prepared by carbonization under high temperature inert atmosphere to convert PAN and PVP into carbon materials. It was found that the PAN‐PVP/ Fe3O4 porous carbon film with 3 wt% Fe3O4 addition had a conductivity of 3.99 S·mm−1 at a thickness of 0.42 mm, and an average EMI SET of 78.9 dB, SEA of 64.8 dB, and SSEt of 1838 dB/(cm2·g−1) in the X‐band, which is a typical wave absorbing material and can meet commercial electromagnetic shielding requirements. This work provides new ideas and methods for the research and development of polymer‐based porous carbonized film as electromagnetic shielding materials. The carbon films with rich porous structure were prepared. Fe3O4 was successfully embedded into the carbon film. Carbon films have an efficient conducting network. Carbon film has excellent electromagnetic shielding performance. The main shielding mode of carbon film is absorption. [ABSTRACT FROM AUTHOR]

The relentless drive toward miniaturization in microelectronic devices has sparked an urgent need for materials that offer both high thermal conductivity (TC) and excellent electrical insulation. Thermal interface materials (TIMs) possessing these dual attributes are highly sought after for modern electronics, but achieving such a combination has proven to be a formidable challenge. In this study, a cutting‐edge solution is presented by developing boron nitride (BN) and graphite films layered silicone rubber composites with exceptional TC and electrical insulation properties. Through a carefully devised stacking‐cutting method, the high orientation degree of both BN and graphite films is successfully preserved, resulting in an unprecedented through‐plane TC of 23.7 Wm−1 K−1 and a remarkably low compressive modulus of 4.85 MPa. Furthermore, the exceptional properties of composites, including low thermal resistance and high resilience rate, make them a reliable and durable option for various applications. Practical tests demonstrate their outstanding heat dissipation performance, significantly reducing CPU temperatures in a computer cooling system. This research work unveils the possible upper limit of TC in BN‐based TIMs and paves the way for their large‐scale practical implementation, particularly in the thermal management of next‐generation electronic devices. [ABSTRACT FROM AUTHOR]

Background: Pathogen bacteria appear and survive on various surfaces made of steel or glass. The existence of these bacteria in different forms causes significant problems in healthcare facilities and society. Therefore, the surface engineering of highly potent antimicrobial coatings is highly important in the 21st century, a period that began with a series of epidemics. Methods: In this study, we prepared two types of photodynamic polyurethane-based composite films encapsulated by N-doped carbon quantum dots and graphene quantum dots irradiated by gamma rays at a dose of 50 kGy, respectively. Further, we investigated their structural, optical, antibacterial, antibiofouling and biocompatibility properties. Results: Nanoelectrical and nanomechanical microscopy measurements revealed deviations in the structure of these quantum dots and polyurethane films. The Young's modulus of elasticity of the carbon and graphene quantum dots was several times lower than that for single-walled carbon nanotubes (SWCNTs) with chirality (6,5). The electrical properties of the carbon and graphene quantum dots were quite similar to those of the SWCNTs (6,5). The polyurethane films with carbon quantum dots were much more elastic and smoother than the films with graphene quantum dots. Antibacterial tests indicated excellent antibacterial activities of these films against a wide range of tested bacteria, whereas the antibiofouling activities of both composite films showed the best results against the Staphylococcus aureus and Escherichia coli biofilms. Biocompatibility studies showed that neither composite film exhibited any cytotoxicity or hemolysis. Conclusions: Obtained results indicate that these composite films could be used as antibacterial surfaces in the healthcare facilities. [ABSTRACT FROM AUTHOR]

Carbon added LiV3O8 films were fabricated using polymer-assisted spin coating method. Here, the influence of carbon black and activated carbon on the characteristics of LiV3O8 were analysed. The structural and morphological characterizations of the films were done, and the Raman studies confirmed the presence of carbon in the coated films. The existence of 4 + and 5 + oxidation states of vanadium in the carbon added films were validated by the XPS spectrum. The improvement in electrical conductivity of all the samples after the addition of carbon was studied using the four-probe method. The carbon added LiV3O8 films displayed better electrochemical performance than the pure LiV3O8 working electrode. A maximum specific capacitance of 216 Fg−1 at a current density of 0.5 Ag−1 was achieved by the activated carbon (0.1 wt%) added to the LiV3O8 film (LVO:PVA:CH0.1). The symmetric device constructed with LVO:PVA:CH0.1 film exhibited excellent retention rate of 99% after 100 cycles. [ABSTRACT FROM AUTHOR]

In this paper, we prepared carbon nanotube (CNT) epoxy composite films and conducted tensile experiments at various temperatures (−40 °C, −10 °C, 20 °C, and 50 °C) and frequencies (1 Hz, 10 Hz, and 20 Hz) using Dynamic Mechanical Analysis (DMA). This study reveals the effects of temperature and frequency on the mechanical properties of CNT films and CNT epoxy composite films. The results indicate that the energy storage modulus of the pure CNT film is approximately 13 times greater than that of the composite material at 20 °C. Additionally, the loss factor of the composite material is about 25 times that of pure epoxy resin and 7 times that of pure CNT film. These findings suggest that the presence of epoxy resin reduces the elastic deformation capacity of the CNT film while enhancing its damping properties. The mechanical properties of CNT films and CNT epoxy composites at varying temperatures and frequencies investigated in this work offer valuable insights for future applications and studies of CNT films and CNT epoxy composites in diverse environments. [ABSTRACT FROM AUTHOR]

In our research described here, a strong acid oxidizing agent was selected to modify the surface of carbon black (CB) to obtain oxidized carbon black (OCB) particles. These OCB particles were then subjected to an ionic bonding reaction with alkaline amine groups present on the surface of octadecylamine polyoxyethylene ether (AC1830) in the form of a paste, resulting in the production of polyether amine-modified oxidized carbon black particles (A-CB). FTIR confirmed the successful production of the A-CB particles. The PVA composite films were prepared using the casting method with varying amounts of A-CB as filler and PVA as the matrix. The films were then analyzed using tensile, scanning electron microscopy, dynamic thermo-mechanical analysis, DSC, and water absorption testing. The results showed that the tensile strength was highest at 3% A-CB, reaching 154.85 MPa. A-CB was well dispersed in PVA at low contents (1% and 3%). The loss modulus, energy storage modulus, crystallinity, and crystallization rate of the A-CB/PVA films improved compared to PVA films. Additionally, the issue of excessive water absorption in A-CB/PVA has been improved. [ABSTRACT FROM AUTHOR]

This study explores the potential of re‐purposing end‐of‐life commercial supercapacitors as electrochemical desalination cells, aligning with circular economy principles. A commercial 500‐Farad supercapacitor was disassembled, and its carbon electrodes underwent various degrees of modification. The most straightforward modification involved NaOH‐etching of the aluminum current collector to produce free‐standing carbon films. More advanced modifications included CO2 activation and binder‐added wet processing of the electrodes. When evaluated as electrodes for electrochemical desalination via capacitive deionization of low‐salinity (20 mM) NaCl solutions, the minimally modified NaOH‐etched carbon electrodes achieved an average desalination capacity of 5.8 mg g−1 and a charge efficiency of 80 %. In contrast, the CO2‐activated, wet‐processed electrodes demonstrated an improved desalination capacity of 7.9 mg g−1 and a charge efficiency above 90 % with stable performance over 20 cycles. These findings highlight the feasibility and effectiveness of recycling supercapacitors for sustainable water desalination applications, offering a promising avenue for resource recovery and re‐purposing in pursuing environmental sustainability. [ABSTRACT FROM AUTHOR]

This paper presents the tribological properties of MXene (Ti3C2Tx) coatings on the surface of impregnated zinc phosphate graphite. MXene coatings were deposited on the surface of the impregnated zinc phosphate graphite by the electrophoretic deposition method at different voltages of 5 V, 10 V, and 15 V. The tribological properties of the MXene coatings were investigated from room temperature to 400 °C in ambient air. The results show that MXene coatings are helpful to improve the tribological properties of the impregnated zinc phosphate graphite at elevated temperatures. The coatings deposited at 5 V have the best anti-friction behaviors among the coatings at the different deposition voltages, which indicates that the MXene coatings deposited at 5 V are suitable for applications in a wide range of temperatures, especially high-temperature environments. The average CoF of the coatings deposited at 5 V is about 0.18 at 200 °C, 0.25 at 300 °C, and 0.21 at 400 °C, respectively. The CoF of the coatings deposited at 15 V is relatively stable with the increase in temperature. Moreover, the high-temperature low-friction mechanism was discussed. The high-temperature low-friction mechanism is attributed to the good self-lubricating behaviors of the impregnated zinc phosphate graphite and the transfer film of the MXene coatings. [ABSTRACT FROM AUTHOR]

Sports monitoring equipment that integrates advanced sensing technology has attracted widespread attention in recent years. Hence, we proposed a TPU/PLA 3D printing film triboelectric nanogenerator (TP‐TENG) to monitor basketball player posture for training effectiveness evaluation. By introducing carbon fibers, TPU/PLA/Carbon film with conductive and positive triboelectric properties was prepared. According to results, the peak power density is 58.38 mW m−2 when the load resistance of 30 MΩ is matched. Nevertheless, when TP‐TENG encounters wrinkles and continues to work for a period of time, its output performance will tend to stabilize. And the open‐circuit voltage (VOC), transfer charge (QSC), and short‐circuit current (ISC) increase to 91 %, 92 %, and 92 %, respectively, almost the same as their original values. Furthermore, the TP‐TENG sensor can recognize human posture in different basketball motion posture, including skipping, squatting, walking, running. This work can help to promote the application of 3D printing TENG in basketball sports monitoring. [ABSTRACT FROM AUTHOR]

A Mach–Zehnder interference (MZI) carbon monoxide gas sensor based on tin dioxide-coated single-mode photonic crystal fiber (ESPCF) was constructed. Using the collapse fusion method, a piece of tin dioxide-coated ESPCF is embedded between the two ends of the seven-core fiber (SCF) to form an SCF-ESPCF-SCF optic-fiber sensor with an MZI sensing structure. To examine the properties of the sensing layer, including its crystalline structure, elemental makeup, and surface appearance, we utilized XRD for diffraction studies, XPS for compositional analysis, and SEM for morphology imaging. The outcomes confirm the successful synthesis of the tin dioxide sensing material, with the formation of a uniform morphology, coating approximately 1.5 μm in thickness on the fiber’s surface. Notably, the sensor exhibits a sensitivity to carbon monoxide of 0.01696 dB/ppm, with activation and reset durations being 60 s and 72 s, correspondingly. The sensor demonstrates high sensitivity, strong selectivity, a favorable linear response, and stability, rendering it highly efficacious for the environmental monitoring of toxic carbon monoxide gas. [ABSTRACT FROM AUTHOR]

The synthesis of various metal acetylene dicarboxylates (MxADC, M=Cu, Ag, Fe, Co, Ni) via new methods are reported. The previously unknown crystal structures for Ag2ADC and FeADC are presented. The behaviour of the different metal dicarboxylates and their role as graphitization catalysts in a printable highly energetic carbon precursor is investigated in detail. Despite the copper compound has the lowest decomposition temperature of all studied acetylene dicarboxylates and is significantly enhancing the conductivity of carbon thin films obtained at low pyrolysis temperatures, the catalytic effect of cobalt and iron on graphitizing carbon results in a superior conductivity in carbon thin films pyrolyzed at lower temperatures down to 600 °C. The newly designed precursors are demonstrated to produce micro‐supercapacitors via 3D‐piezoelectric inkjet technique at low pyrolysis temperature. [ABSTRACT FROM AUTHOR]

CO gas sensing properties of 1-D ZnO nanostructures deposited on films of Multi-Wall carbon nanotubes were investigated using a vapor transport approach. X-ray powder diffraction, scanning electron microscopy, transmission electron microscopy, high resolution transmission electron microscopy, energy dispersive X-ray, Raman spectroscopy, diffused reflectance spectroscopy, and photoluminescence, techniques were used to carry out the structural, morphological, and optical characterizations. The development of carbon-doped hybrid MWCNTs/ZnO nanostructures was demonstrated by the current results. The synthesized nanostructures were dense tapering belts and pedal-like crystalline structures as evidenced by their structural and morphological characteristics. Multiple networks of pure ZnO and hybrid MWCNTs-ZnO nanostructures were used to synthesize the gas sensors. Doped ZnO nanostructures sensing technique for CO gas detection was investigated in the present study. The combined impact of ZnO and MWCNTs was shown to be beneficial in boosting the response towards CO gas, as the response to CO gas at a concentration of 20 parts per million (ppm) was found to be five-times greater than that of ZnO sensors with good stability. [Display omitted] [ABSTRACT FROM AUTHOR]

A novel surface modification technique for graphite films (GF) to improve the interface thermal resistance with epoxy resin was presented. By utilizing the self‐polymerization of dopamine (PDA), dopamine micro and nanoparticles were formed on the surface of the GF. Subsequently, the surface of the epoxy resin was functionalized with polydopamine (PDA) through grafting of the silane coupling agent 3‐glycidyl ether oxy‐propyl trimethoxy silane (GOPTS), enabling the introduction of epoxy resin groups onto the surface of the GF. Employing a simple folding technique, a three‐dimensional GF network (3DGF) was constructed, in which modified GF was successfully incorporated into the polymer matrix. The results showed that the 3DGF network further promoted the effective transfer of heat and electrons within the composite, leading to a significant improvement in thermal and electrothermal conversion performance. The prepared 3DGPGF/epoxy resin composite exhibits high thermal conductivity (7.14 W/mK) at a relatively low GF loading (31.9 wt%). Under a voltage of 12 V, the surface temperature of the sample rapidly rises from room temperature to 130°C within 200 s, and can completely melt ice cubes within 60 s. These results indicate that epoxy‐silane‐dopamine‐modified graphite film can be a promising candidate material, and this work provides a promising strategy for designing and manufacturing high‐performance composites with improved thermal properties. The developed method has the potential to be extended to other polymer matrices and fillers, and the prepared composites have enormous potential in various applications. [ABSTRACT FROM AUTHOR]

This work presents a promising method to prepare pure zinc oxide (ZnO) films and carbon nanoparticles (CNPs) decorated ZnO (CNP/ZnO) nanostructured films as glucose sensors. ZnO nanostructure film was grown on Zn foil via the anodisation method, whereas the carbon nanoparticles were synthesised by the hydrothermal method, the decoration process of carbon nanoparticles on ZnO film nanocomposites was conducted using the ultrasonication method. Numerous experiments were conducted, such as microstructure observation, crystallinity analysis, and electrochemical property research. The nanostructures were ascertained by energy-dispersive X-ray spectroscopy (EDX), field-emission scanning electron microscopy (FE-SEM), transmission electron microscope (TEM), UV-vis spectroscopy, photoluminescence (PL) measurements, and X-ray diffraction (XRD). ZnO NPs displayed a structure with an average crystallite size of 5.12–13.47 nm, and the PL emission spectra were found to be in the 387 nm range, ZnO films were created by annealing ZnO samples at 200°C for 2 h, and FE-SEM presented nanoparticle-like shapes with a particle size range of (20–50 nm) for voltage anodisation (6 v). This led to an elevation of the energy gap to 3.20 eV. The electrochemical characterisation of the CNPs/ZnO nanostructures refines remarkably the sensitivity to glucose via pure zinc oxide nanostructures. The CNP/ZnO nanostructures demonstrated improved glucose-sensing ability with a sensitivity value of 2827 µA. m${M^{ - 1}}$M−1. The low detection limit is 0.8 mm with a linear range from (0.3 mm to 1 mm). The sensitivity and repeatability of the biosensors were assessed by measuring and analysing their I–V characteristics at different glucose concentrations. Based on a straightforward, affordable, and innovative sensor design, this result validates the sensor’s significant potential as a high-performance nonenzymatic glucose sensor. It was observed that when zinc oxide films were decorated with carbon nanoparticles, there was an increase in the sensitivity of glucose detection. This is due to an increase in charge transfer and conductivity, as well as an increase in the oxidation and reduction process. [ABSTRACT FROM AUTHOR]

This work describes the fabrication of a composite supercapacitor electrode made of Cu-doped BiFeO 3 (Cu-BFO) films on an activated carbon (AC) electrode using radio-frequency (RF) magnetron sputtering. To prevent exfoliation of Cu-BFO and AC upon immersion in an electrolyte, the nickel foam sandwiching electrode technique was introduced. The Cu-BFO films significantly enhanced electrochemical properties, increasing specific capacitance by up to 151% compared to that of an AC electrode. This was attributed to Faradaic reactions and specific surface area in the Cu-BFO/AC electrode. The highest specific capacitance achieved was 169 F g - 1 at 0.5 A g - 1 , and cycling stability retention was 93.12% after 500 cycles. However, the remaining percentage of the specific capacitance decreased differently with increasing thickness, which is also discussed. Furthermore, an asymmetric supercapacitor using Cu-BFO/AC and AC electrodes demonstrated a high energy density of 4.71 Wh kg - 1 , power density of 2.66 kW kg - 1 , and over 90% retention after 1000 cycles, highlighting its durability. The uniform RF magnetron sputtering deposition is vital for mass production. Combined with impressive retention in asymmetric supercapacitors, this scalability suggests a promising pathway for large-scale manufacturing. Consequently, this work could pave the way for the large-scale production of supercapacitors. [ABSTRACT FROM AUTHOR]

High-performance and cost-efficient electrocatalysts and electrodes are needed to improve the hydrogen evolution reaction (HER) for the hydrogen (H2) generation in electrolysers, including microbial electrolysis cells (MECs). In this study, free-standing carbon nanofiber (CNF) films with supported cobalt phosphide nanoparticles have been prepared by means of an up-scalable electrospinning process followed by a thermal treatment under controlled conditions. The produced cobalt phosphide-supported CNF films show to be nanoporous (pore volume up to 0.33 cm3 g−1) with a high surface area (up to 502 m2 g−1) and with a suitable catalyst mass loading (up to 0.49 mg cm−2). Values of overpotential less than 140 mV at 10 mA cm−2 have been reached for the HER in alkaline media (1 M KOH), which demonstrates a high activity. The high electrical conductivity together with the mechanical stability of the free-standing CNF films allowed their direct use as cathodes in a MEC reactor, resulting in an exceptionally low voltage operation (0.75 V) with a current density demand of 5.4 A m−2. This enabled the production of H2 with an energy consumption below 30 kWh kg−1 H2, which is highly efficient. [ABSTRACT FROM AUTHOR]

Ternary carbonate salts (Li2CO3-Na2CO3-K2CO3) are promising heat transfer fluids to increase the efficiency of the electric power in concentrated solar power (CSP) technology. However, the corrosion produced at high operating temperatures is a key challenge to tackle for employing cost-effective steels as construction materials in CSP. In this work, the use of stainless steels with amorphous carbon was investigated, for the first time, as a surface modification method to mitigate the corrosion of structural CSP materials by molten salts. In doing so, an amorphous carbon (a-C) film of 100 nm in thickness was deposited on the 301LN stainless steel's surface by the carbon thread evaporation technique. The corrosion behavior of the 301LN was assessed in carbonate salt at 600 °C for 1000 h. This film decomposed forming carbide layers, contributing to corrosion mitigation due to the generation of denser oxide layers, decreasing the Li+ diffusion through the stainless steel. [ABSTRACT FROM AUTHOR]

In order to utilize the longer wavelength light, the surface sulfurization of MoO3 was carried out. The photocurrent responses to typical 650, 808, 980, and 1064 nm light sources with Au gap electrodes were investigated. The results showed that the surface S–O exchange of MoO3 improved the interfacial charge transfer in the range of the broadband light spectrum. The S and O can be exchanged on the surface of MoO3 nanosheets under the hydrothermal condition, leading to the formation of a surface MoOx/MoS2 heterojunction. The interfacial interaction between the MoO3 nanosheets and MoS2 easily generated free electrons and holes, and it effectively avoided the recombination of photogenerated carriers. Meanwhile, the surface S-doping of MoO3 also resulted in the generation of an oxygen vacancy and sulfur vacancy on MoO3−xS2−y. The plasmonic characteristics of MoO3−x contributed to the enhancement of the interfacial charge transfer by photoexcitation. Otherwise, even with zero bias applied, a good photoelectric signal was still obtained with polyimide film substrates and carbon electrodes. This indicates that the formation of the heterojunction generates a strong built-in electric field that drives the photogenerated carrier transport, which can be self-powered. This study provides a simple and low-cost method for the surface functionalization of some metal oxides with a wide bandgap. [ABSTRACT FROM AUTHOR]

Surface roughness control of end products is increasingly becoming significant, especially with the miniaturization trends in the semiconductor industry. Ultra-thin amorphous carbon (a-C) films offer a prime solution to optimize surface roughness due to their outstanding characteristics. In this study, hydrogenated a-C films are deposited on two-dimensional quartz plates and three-dimensional quartz molds to evaluate the growth mechanisms and changes in the surface roughness, which is supported by molecular dynamics simulations. Results reveal that surface roughness encounters multiple variations until it reaches stable values. These fluctuations are categorized into four different stages which provide a concrete understanding of various growing mechanisms at each stage. Different behavior of the atoms in the top layers is recorded in the cases of normal and grazing incidents of carbon atoms. Lower surface roughness values are obtained at low-angle deposition. Interestingly, surface smoothing is attained on the sidewalls of the nanotrench mold where the deposition occurs with high incident ion angles. [ABSTRACT FROM AUTHOR]

The rapid development of photonic integrated circuits (PICs) and their applications in various fields of science and technology requires the creation of easy-to-manufacture high-speed integrated detectors. In this work, we fabricated and studied planar waveguide-integrated bolometers based on a thin film of single-walled carbon nanotubes (SWCNTs) on the silicon nitride platform. This bolometer showed good internal responsivity and a high bandwidth > 1 GHz. In-depth analysis allowed us to retrieve the main parameters of the SWCNT film that govern the bolometric response that can be difficult to measure directly. The results obtained show a promising prospect of using SWCNT bolometers for PIC applications. [ABSTRACT FROM AUTHOR]

Thin composite films hold great promise for microwave devices for microwave absorption. This work mainly focuses on the investigation of the microwave absorption and mechanical studies of a composite thin film of activated carbon and manganese ferrite as conductive fillers within a polyvinylidene fluoride (PVDF) matrix. The production of activated carbon was successfully accomplished using a pyrolysis technique. Composite films consisting of polyvinylidene fluoride (PVDF) and activated carbon‐manganese ferrite were fabricated using a solution blending method. The composite films maintained a consistent concentration of activated carbon at 5 wt%. The characterization of the materials was conducted using scanning electron microscopy and X‐ray diffraction. The composite consists of 3 wt% of MnFe2O4 and 5 wt% Activated carbon/PVDF showed exceptional absorption properties and achieved a minimum reflection loss of around −38 dB at a frequency of 8–12 GHz at a thickness of 2 mm. Significantly, the composite film exhibited a greater tensile strength than the PVDF film. The results of our study highlighted the enhanced microwave absorption and economical manufacturing technique for producing composite films. These films exhibit promising microwave‐absorbing properties in stealth applications. Highlights: A facile strategy to fabricate thin film PVDF composites was proposed.Novel activated carbon was synthesized to enhance the conductivity.Achieved reflection loss of around −38 dB at a frequency of 8–12 GHz.Synergistic effects of fillers enhanced dielectric and magnetic losses.Exhibited efficient mechanical performance and microwave absorption. [ABSTRACT FROM AUTHOR]

Fluorine-doped zinc oxide (ZnO:F) thin films are valued for their potential as transparent conductive materials, particularly in optoelectronic applications. In this work, the deposition of highly conductive and transparent fluorine-doped ZnO thin films, deposited by chemical spray on glass substrates is reported. The effect of acetic (AcAc) in the initial fresh solution on Haacke's Figure of Merit (Φ) of both zinc oxide (ZnO) and fluorine-doped zinc oxide (ZnO:F) thin films was studied. The substrate temperature was fixed to 450°C, and two deposition times (8 and 14 min) were tested. Accordingly, the optical and transport properties, as well as the structural and morphological characteristics of the films were measured. The results indicate that the samples are polycrystalline in all cases and exhibit a wurtzite-type structure of ZnO. The variation of AcAc in the starting solution causes a switch in preferential growth from (002) to (001). As the AcAc content increases, the surface morphology of the films reveals the formation of well-defined hexagonal grains, and the grain size increases. Conversely, the transmittance decreases as the acetic acid increases, which can attributed to carbon incorporation into the film. In addition, the band gap values of the films varied from 3.2 to 3.4 eV. Also, as the acetic acid concentration increased, a drop in the electrical resistivity of ZnO thin films on the order of 0.016 Ω ⋅ cm was found for the ZnO:F films deposited with fresh solution for 14 min. This can be ascribed to a dense acetic cloud formed during the synthesis process, trapping volatile F species that incorporate into the ZnO lattice. This enhances Haacke's Figure of Merit of ZnO:F films deposited with a fresh solution, demonstrating their potential use for application as transparent conductive films. This contrasts with other synthesis methods that require longer aging time in the precursor solution, making these findings useful for large-scale and more efficient production of transparent conductive films. [ABSTRACT FROM AUTHOR]

The obtention of luminescent SiOxCy:H thin films deposited by the HW-CVD technique is reported here. We study the effect of different monomethyl-silane (MMS) flow rates on the films properties. An increase in the emission bandwidth and a red-shift was observed when the MMS flow increased. The luminescence was related to optical transitions in band tail states and with less contribution from quantum confinement effects. After, the films were annealed at 750 °C in nitrogen. The annealed film deposited at the highest MMS flow showed an emission spectrum like the as-deposited film, suggesting the same emission mechanisms. By contrast, the annealed film deposited at the lowest MMS flow showed two emission bands. These bands are due to the activation of radiative defects related to oxygen-deficient centers. MOS-like structures were fabricated as electroluminescent devices using the annealed films. Only the structure of the film with the highest carbon content showed light emission in a broad band in the visible spectrum region in forward bias, with a maximum centered close to 850 nm. The light emission mechanism was related to electron thermalization in the band tail states and a direct hole injection into deep states. The trap-assisted tunneling, Poole–Frenkel emissions and Fowler–Nordheim tunneling were proposed as the charge transport mechanism. [ABSTRACT FROM AUTHOR]

TC4 titanium alloy has been widely used in the automotive field due to its exceptional properties. However, inherent defects such as low hardness and poor wear resistance for TC4 alloy limited its wider application. The microarc oxidation (MAO) technique was employed in this paper to prepare MAO coatings on TC4 titanium alloy. The microstructure, phase structure, mechanical properties, and tribological performance were systematically evaluated. The results show that the coating contains a large amount of rutile TiO2 hard phase after MAO treatment, which significantly improves the mechanical properties of the substrate. The hardness of the MAO coating can reach 581 HV.05. Furthermore, the synergistic lubrication effect of onion‐like carbon (OLC) nanoparticles and organic molybdenum dithiocarbamate (MoDTC) in PAO oil was observed for MAO‐treated TC4. Particularly, when.01 wt.% OLC is used with 1 wt.% MoDTC oil, the coefficient of friction (COF) decreases to.062, and the wear rate decreases to 4.3 × 10−7 mm3/Nm. Combined Raman and X‐ray photoelectron spectroscopy (XPS) analysis indicate that OLC is deposited on coating area to form a lubricating carbon film. Additionally, OLC can promote the decomposition of MoDTC during sliding to generate a tribofilm containing MoS2. [ABSTRACT FROM AUTHOR]

Alumina, as a pivotal ceramic material extensively utilized in contemporary applications, the surface modification and enhancement of tribological properties are crucial. In this study, reactive magnetron sputtering was employed to deposit Ti, Si co-doped hydrogen-free (TiSi/a-C), and hydrogenated amorphous carbon films (TiSi/a-C:H) with a thickness exceeding 7 μm onto the surface of alumina ceramic substrates. Utilizing the design of the film structure, the difficulty of film-substrate adhesion was resolved by controlling the deposition time to influence the growth rate of the film, thereby enabling the reliable fabrication of thick films. The adhesion of the TiSi/a-C film exhibits the highest value, with an Lc1 value of 36.7 N. The hardness of the TiSi/a-C:H reaches a maximum of 15.2 GPa, and the hardness is closely correlated with the reaction gas utilized during its depositional process. The wear rate of amorphous carbon film decreases by 34 times compared to alumina substrate. During the dissociation of CH 4 at a high hydrogen-to-carbon ratio, more hydrogen atoms are involved in the chemical reaction. The introduction of hydrogen elevates the H/E and sp3/sp2 ratios within the film, thereby favoring the generation of low-friction surfaces and refining the tribological performance of alumina ceramics. [ABSTRACT FROM AUTHOR]

Lightweight, flexible and highly conductive electromagnetic interference (EMI) shielding materials are of great importance for protecting flexible electronics and telecommunication devices under extremely high temperature conditions. A potential solution is to incorporate ceramic phases with highly conductive flexible carbon nanotube films to improve their thermal stability. However, the grain size of the ceramic phase generally increased significantly as the temperature increased which led to brittleness. In this work, a highly flexible carbon nanotube (CNT) film with controllable ceramic nanocrystals was prepared by precursor infiltration and pyrolysis. The silicon carbide (SiC) grain size in the nanocomposites was inhibited by the spatial confinement effects of CNT networks and a second amorphous SiBCN phase. The SiC grain size in the composite film decreased with the increase of the SiBCN content and the elongation at break of the nanocomposites improved significantly by 45 %. Moreover, the initial thermogravimetric temperature of the prepared films has been significantly improved to exceed 600 °C compared to the raw CNT film. Importantly, the nanocomposite film exhibited an average EMI shielding effectiveness of ∼40 dB from 8.2 to 12.4 GHz. Benefiting from the ultrafine grain size, the nanocomposite films could be folded and extended without micro-cracks over 1000 times. Combining the performance and mechanical properties of the nanocomposite film, this approach provides important guidance for designing high-performance CNT-based electromagnetic shielding materials with superior flexibility at elevated temperatures. [ABSTRACT FROM AUTHOR]

In carbon allotropes, interfacial engineering of various sp2 nanocarbon building blocks has shown great promise in designing and fabricating creative nanocarbon assemblies with novel structural and functional properties. Here, a robust, flexible, metal‐like heterostructured carbon nanotube (CNT) film formed of amorphous graphene nanosheets (AGNs) on CNT networked film is demonstrated, presenting a sp3‐sp2 dominated interfacial heterostructure. Extensive characterization reveals that AGN exhibits a complete absence of long‐range periodicity with twisty six‐member rings. Such 2D graphene mailed 1D CNT structure endows the heterostructured carbon nanocomposite film with a combination of unique properties, including surface nano‐flattening (flatness fourfold of the raw CNT film), excellent anti‐wear performance, greatly enhanced modulus (enhanced by 400%), hardness (enhanced by 300 times), and conductivity (enhanced by 270%). Unlike conventional carbon‐based materials, such flexible films show distinct substantial deformability and rapid resilience over wide temperatures (−196–≈1300 °C), which facilitate the design of new‐concept lightweight high‐temperature resistant and shape‐transformable materials for advanced aerospace applications under extreme conditions. [ABSTRACT FROM AUTHOR]

Copper (Cu) is widely used as an industrial electrode due to its high electrical conductivity, mechanical properties, and cost‐effectiveness. However, Cu is susceptible to corrosion, which degrades device performance over time. Although various methods (alloying, physical passivation, surface treatment, etc.) are introduced to address the corrosion issue, they can cause decreased conductivity or vertical insulation. Here, using the nitrogen‐doped amorphous carbon (a‐C:N) thin film is proposed as a substrate on which Cu is directly deposited. This simple method significantly inhibits corrosion of ultrathin Cu (<20 nm) films in humid conditions, enabling the fabrication of ultrathin electronic circuit boards without corrosion under ambient conditions. This study investigates the origin of corrosion resistance through comprehensive microscopic/spectroscopic characterizations and density‐functional theory (DFT) calculations: i) diffusion of Cu atoms into the a‐C:N driven by stable C‐Cu‐N bond formation, ii) diffusion of N atoms from the a‐C:N to the Cu layer heading the top surface, which is the thermodynamically preferred location for N, and iii) the doped N atoms in Cu layer suppress the inclusion of O into the Cu lattice. By leveraging the ultrathinness and deformability of the circuit board, a transparent electrode and a crumpleable LED lighting device are demonstrated. [ABSTRACT FROM AUTHOR]

Due to the unique structures and superior chemical and physical properties, onion carbon holds great appeal for various applications, such as lubrication, energy storage and catalysis. However, conventional synthesis methods for onion carbon are often complex, resulting in products of low purity and quantity. Here we report the one-step combustion synthesis of onion carbon with high purity and tunable particle size by employing naphthalene as the precursor, and investigated the effect of combustion temperatures on the formation mechanism of onion carbon, leading to the achievement of controlled preparation of onion carbon. The size of synthesized onion carbon particles ranges from 50 to 190 nm, which increases with the synthesis temperature and shows a wider distribution at higher temperatures. Owing to the abundant oxygen-containing functional groups, as-synthesized onion carbon exhibits prolonged stability and solubility in organic solvents such as ethanol and glycerol. Furthermore, we tested the friction performance of stainless steel coated with onion carbon films by ball-on-disk mode on the upper surface with different loads and sliding speeds. Deposited onion carbon film improved the friction performance of stainless steel at high load and sliding speed. [Display omitted] [ABSTRACT FROM AUTHOR]

To obtain carbon dots (CDs) with narrow full width at half maximum (FWHM) and long-wavelength emission, carbon sources with high conjugate sizes and abundant functional groups can be employed to synthesize CDs. In this study, orange-emissive carbon dots (OCDs) were synthesized with phloroglucinol and rhodamine B as precursors. When the molar ratio of them was 30:1, and ethanol was served as the solvent, OCDs with optimized emission wavelength at approximately 580 nm, an FWHM of 30 nm, and a quantum yield (QY) of 27.31% were obtained. Subsequently, the OCDs were incorporated into polyvinyl alcohol (PVA) to fabricate solid-state OCD/PVA fluorescent films, which exhibited an FWHM of 47 nm. The PVA matrix facilitated the dispersion of OCDs, thereby suppressing non-radiative energy transfer among the OCDs and enhancing luminescence efficiency. Consequently, compared with OCDs, the OCD/PVA film exhibited significant luminescent enhancement, and the QY of the composite film was increased to 84.74%. Moreover, OCD/PVA film showed good transmittance and thermal stability. This research offers a solid theoretical and experimental foundation for the potential applications of CDs in the field of solid-state lighting. [ABSTRACT FROM AUTHOR]

Amorphous carbon is recognized as an excellent lubricating material; however, its tribological properties are significantly influenced by humidity. To elucidate the mechanism underlying this humidity dependence and to propose a novel enhancement method, we investigated and compared the tribological properties of hydrogenated amorphous carbon (a-C:H) and amorphous carbon/gold (a-C/Au) composite films. First, the friction coefficient of these carbon films under different humidity conditions was tested using a rotational ball-on-disk tribometer. Subsequently, we analyzed the morphology and structure of the sliding interface employing optical microscopy (OM), Raman spectroscopy, transmission electron microscopy (TEM), and high-resolution transmission electron microscopy (HRTEM). Finally, first-principle calculations were carried out to calculate the adsorption energy of water molecules on different surfaces. The results indicate that the friction coefficient of a-C:H film and the area of transfer film increase with the increase of humidity. This phenomenon can be attributed to the fact that water molecules enhance the interaction between the a-C:H film and steel counterfaces. Notably, in contrast, the friction coefficient of a-C/Au film demonstrates low sensitivity to humidity due to the formation of an Au transfer film that exhibits weak interaction with water molecules. These findings provide a promising strategy for developing environment-adaptive amorphous carbon films and play an important role in promoting the development of intelligent lubricating film. [ABSTRACT FROM AUTHOR]

Assembly of graphite structures through pencil drawn method is considered among the most facile and inexpensive approaches for a wide range of electronic and optoelectronic applications. However, the typical limitation of this methodology is that the films and structures can be drawn on a very limited number of substrates. Here, we report a novel methodology for the transfer of pencil drawn graphite films on desired substrate. The graphite films are transferred from cellulose paper, textile and wood paper onto flexible and transparent acrylic tape. The novel wood paper substrate is also used for the fabrication of bar device using a mask which is then transferred onto the acrylic tape. TiO 2 nanoparticles paste is coated on the surface of transferred bar device. Scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction analysis, and UV–visible spectroscopy of graphite and graphite/TiO 2 -NPs electrodes are performed respectively to study their morphological, compositional, structural and optical features. The fabricated device acts as a UV photodetector and delivers a photocurrent as higher as 197.68 μA, photoresponsivity of 8.94 mA W−1, detectivity of 4.16 × 109 Jones at bias voltage of 5 V, response time of ∼860 ms and recovery time of ∼890 ms. The flexibility of the demonstrated photodetector is evaluated through recording changes in photocurrent under bending positions from 0 to 150°, and after employing bending cycles up to 1000. The results show that the fabrication of photodetector is facile and low-cost, and it offers valuable working compatibility under bending strains. Moreover, the flexibility of photodetectors enables their effective integration with human skin and clothes for human health monitoring applications. [ABSTRACT FROM AUTHOR]

The quasi‐static tensile properties of carbon nanotube (CNT) films have been extensively investigated, yet research on their impact tensile properties at high strain rates remains scarce. In this article, CNT films prepared by floating catalyst chemical vapor deposition (FCCVD) method were densely arranged by chlorosulfuric acid (CSA) under wet stretching. The Instron 3365 and miniaturized split Hopkinson tension bar (SHTB) were used to conduct tensile testing at different strain rates. The findings reveal that CSA wet‐stretching markedly enhances the density and orientation of CNT films, resulting in significant improvements in tensile properties with a notable strain rate effect. Specifically, when immersed for 60 s under a draft ratio of 40% and a strain rate of 1900 s−1, the densified CNT films exhibit maximum stress and energy absorption values of 777.44 MPa and 54.79 MJ/m3, respectively, achieving a 637.1% and 425.7% increase compared with the original film. This research provides a convenient and feasible strategy to prepare CNT films with high energy absorption tolerance across various strain rates, thus expanding the practical application potential of CNT films. Highlights: The study innovates a posttreatment way to produce superior FCCVD CNT films.CSA treatment and wet stretching enhance CNT films' mechanical properties.Dynamic fracture strength boosts over 600% and energy absorption raises over 400%.CSA can purify FCCVD‐prepared CNT films, greatly improving their properties.The Prep can be effectively integrated with the direct spinning process. [ABSTRACT FROM AUTHOR]

To achieve high‐quality hard carbon nanofibers (HCNFs), and particularly flexible HCNFs films is the eternal pursuit from low‐cost coal pitch (CP). However, it is still trapped seriously by the inborn bottleneck of low‐softening‐point (LSP) characteristics of CP itself. Herein, an efficient Bi(NO3)3·5H2O‐assisted electrospinning‐carbonization methodology is creatively devised to obtain flexible HCNFs films directly from LSP CP. The essential roles of Bi(NO3)3·5H2O and pre‐oxidation in constructing flexible films are rationally proposed. With further regulation in Bi(NO3)3·5H2O dosage and calcination temperatures, specific micro‐structures/morphologies of flexible HCNFs films are finely optimized. The optimum HCNFs‐1.2 film is endowed with robust structural flexibility/stability, high‐content active oxygen/nitrogen groups, abundant graphic microcrystalline zones of large interlayer spacing, and convenient ion‐diffusion channels. Thanks to such remarkable merits, HCNFs‐1.2 retains a large reversible capacity of 125.3 mAh g‒1 over 1000 cycles at 1.0 A g‒1, when evaluated as a self‐supporting film anode for sodium dual‐ion batteries (SDIBs). Furthermore, the HCNFs‐1.2‐based SDIBs deliver a specific capacity of 90.9 mAh g‒1 at 0.1 A g‒1, along with a capacity retention of 78.4% after 1500 cycles at 1.0 A g‒1. The insightful understanding here will provide meaningful guidance for rational design of advanced flexible film electrodes toward next‐generation SDIBs and beyond. [ABSTRACT FROM AUTHOR]