Carbon Nanocoils Research Articles

Enhancing luminescence in bio-cellulose derived carbon microcoils through europium incorporation: A pathway to high-performance UV luminophores

Bio-cellulose derived carbon microcoils (BCMC) are renowned for their distinctive helical structure, sustainability, and renewability, making them highly versatile for applications such as microwave absorption, water purification, and energy storage. Despite extensive research on carbon microcoils or nanocoils, the luminescent properties of BCMC remain largely unexplored. This study delves into the luminescence characteristics of BCMC extracted from recycled tea leaves, revealing a broad spectrum of multicolor emissions including ultraviolet (355 nm, 396 nm), blue (467 nm), and near-infrared (764 nm). These emissions are attributed to BCMC's distinctive three-dimensional helical configuration and its rich array of oxygen-containing functional groups. Incorporating europium further tailors the photoluminescent properties of BCMC, significantly amplifying UV and blue light emissions. Additionally, annealing improves UV emission, showcasing the potential for enhanced luminescence performance. This research not only deepens our understanding of sustainable luminescent materials but also paves the way for developing advanced UV luminophores with diverse applications.

Construction of Chiral-Magnetic-Dielectric Trinity Structures with Different Magnetic Systems for Efficient Low-Frequency Microwave Absorption.

The fabrication of carbon nanocoil (CNC)-based chiral-dielectric-magnetic trinity composites holds great significance in low-frequency microwave absorption fields. However, it is not clear that how the different magnetic systems affect the magnetic and frequency responses of the composites. Herein, four types of magnetic metals, FeCo, CoNi, FeNi, and FeCoNi, are selected to be combined with the chiral templates respectively, resulting in four types of chiral-dielectric-magnetic composites with similar morphology. The CNC templates endow all the composites with excellent dielectric loss. Further permeability analysis and the micro-magnetic simulation confirm that the frequency response region can be well adjusted by changing the magnetic systems with specific magnetic resonance modes and magnetic domain motion. Due to the synergistic effect between magnetism, chirality, and dielectricity, the FeNi-based composites exhibit the best low-frequency microwave absorption performance. The minimum RL of -60.7 dB is achieved at 6.7 GHz with an ultra-low filling ratio of 10%, and the EAB value in low-frequency region is extended to 3.7 GHz. This study provides further guidelines for the design of the chiral-dielectric-magnetic trinity composites in low-frequency microwave absorption.

Integration of carbon microsheets and helical carbon nanocoils for efficient microwave absorption

The integration of multi-dimensional materials is a powerful approach for the construction of high-performance microwave absorbers. In this work, 2D-like carbon microsheets (CMSs) have been directly synthesized on the surfaces of 3D helical carbon nanocoils (CNCs) through a Cu catalyzed chemical vapor deposition process. The junctions formed between CMSs and CNCs create numerous polarization sites, which enhances interfacial polarization. The planar morphology of CMSs is beneficial to enhance the multiple scattering of microwave, while the 3D helical CNCs prevent the aggregation of 2D-like CMSs and simultaneously enhance the conductive loss and cross-polarization loss. By controlling the growth time, the morphologies of CMS are precisely tailored and their impedance matching is adjusted. Consequently, CMS/CNC demonstrates exceptional microwave absorption (MA) performance with a broad effective bandwidth of 6.5 GHz and a minimum reflection loss of −39.3 dB at a remarkably low filling ratio of 4 wt%. This study provides a novel multi-dimensional integrated structure for efficient MA.

Fabrication of Micro‐Mesopores on Spiral Carbon Nanocoils and Simultaneous Doping with Oxygen to Expand Microwave Absorption Bandwidth

AbstractThe exceptional benefits of structural defects and doped atoms in carbon network regarding electromagnetic properties inspire the design of advanced carbon‐based microwave absorption (MA) materials. However, excessive structural defects decline the physical properties of materials, especially their conductivity. Therefore, it is a great challenge to balance structural defects and doped atoms to optimize conductive behavior for carbon‐based MA materials. The spiral carbon nanocoil (CNC), with coexisting amorphous and polycrystalline carbon structures and moderate conductivity, has significant MA properties but lacks pores and doped atoms. Herein, the amorphous carbon parts with relatively weak C─C bond energies are preferentially oxidized at 500 °C in air atmosphere to create pores and combine O atoms in the bodies of CNCs. Furthermore, the mechanism prioritizing the formation of O doping over defects is discovered. Benefiting from the synergistic interplay of structural defects and O dopants, the O‐enriched porous CNCs demonstrate enhanced conduction and polarization losses than the pure CNCs, realizing a wide effective absorption bandwidth of 7.3 GHz at a filling ratio of only 3 wt.%. Theoretical calculations further support these experimental results. The combination of structural defects and doped atoms may serve as an effective pathway for unlocking tunable dielectric properties of carbon‐based materials.

Manganese tetraphenylporphyrin and carbon nanocoil interface-based electrochemical sensing of tyrosine.

Tyrosine is one of the essential metabolites present in the human body for nutritional maintenance and normal physiological functioning. Its concentration in the body is crucial in predicting various hereditary, emotional, and physiological disorders. Therefore, quantitative monitoring of tyrosine in clinical samples is indispensable. We state the use of carbon nanocoils/manganese tetraphenylporphyrin convened glassy carbon electrode (CNC/MnTPP/GC) for the streamlined electrochemical sensing of tyrosine. Cutting-edge analytical techniques were employed to perform a comprehensive physicochemical analysis of the synthesized materials. To investigate the electrochemical properties, various techniques such as cyclic voltammetry (CV), differential pulse voltammetry (DPV), electrochemical impedance spectroscopy, and chronocoulometry were employed. CNC/MnTPP/GC displayed an optimal response at pH 5 and exhibited remarkable linearity within the concentration range of 0.05 to 100 μM for tyrosine. Using DPV, it demonstrated a low limit of detection (21 nM ± 1.17) and a sensitivity of 0.12 μA μM-1 cm-2. CNC/MnTPP/GC displayed excellent performance in terms of repeatability, reproducibility, and stability for up to 30 days, making it suitable for real-time analysis, particularly in the analysis of tyrosine in blood serum. Notably, CNC/MnTPP/GC showcased a superior detection limit compared to previously reported methods.

A Light-Driven Carbon Nanocoil Microrobot

Mobile microrobots are of great scientific significance. However, external actuation and control methods are still challenging to conduct. We present a single carbon nanocoil (CNC) microrobot induced by an NIR laser beam, capable of light-driven locomotion and photothermal actuation. This research demonstrates that CNC-based microrobots rolls away from the focal spot when the laser beam is focused near the CNC. The maximum translational distance of a CNC microrobot increases with an increase in laser power, and the direction of motion is guided by controlling the focusing position of NIR. CNC-based microrobots can load and transport multiple cells under NIR light irradiation, resulting from the temperature gradient generated by photothermal conversion, which causes thermophoresis. The hydrophobic surface and unique helical structure of CNCs are beneficial to the underwater drag reduction in CNC microrobots’ motion and the adhesion of cells on CNC microrobots. Therefore, CNC microrobots, as cell vectors driven by a laser beam, may find applications in a wide range of biomedical applications. In addition, the rotation of a CNC powered by a laser beam provides promising prospects for the future of nanomechanical devices using a carbon nanocoil as a micro/nanomotor.

Construction of chiral magnetic structure with enhancement in magnetic coupling for efficient Low-Frequency microwave absorption

Construction of chiral magnetic structure is considered as a promising strategy to achieve efficient low frequency microwave absorption. However, it is not clear that how the magnetic loss is enhanced by the chiral morphology. Herein, a novel chiral magnetic structure containing FeCo2O4-FeCo nanosheets has been constructed by using helical carbon nanocoils (CNCs) as the chiral template. For comparison, the FeCo2O4-FeCo nanosheets are also combined with the linear carbon nanofibers (CNFs). The enhanced magnetic coupling between FeCo2O4-FeCo nanosheets and the magnetic anisotropy induced by the chiral structure are confirmed by the off-axis electron holography and the micro-magnetic simulation. Due to the synergistic effect between chirality, magnetism, and dielectricity, the chiral magnetic structure exhibits superior microwave absorption performance than the linear one with a wide effective bandwidth of 7.1 GHz at an ultra-low filling ratio of 8 %. Meanwhile, the minimum RL value of −60.7 dB is achieved at low frequency (6 GHz). This study provides further evidence of the special mechanisms of the chiral structure for microwave absorption.

Probing the Thermoelectricity in Single Carbon Nanocoil for the Design of a Nano Thermocouple

Probing the Thermoelectricity in Single Carbon Nanocoil for the Design of a Nano Thermocouple

Microwave-Solvothermal Synthesis of Mesoporous CeO2/CNCs Nanocomposite for Enhanced Room Temperature NO2 Detection.

Nitrogen dioxide (NO2) gas sensors are pivotal in upholding environmental integrity and human health, necessitating heightened sensitivity and exceptional selectivity. Despite the prevalent use of metal oxide semiconductors (MOSs) for NO2 detection, extant solutions exhibit shortcomings in meeting practical application criteria, specifically in response, selectivity, and operational temperatures. Here, we successfully employed a facile microwave-solvothermal method to synthesize a mesoporous CeO2/CNCs nanocomposite. This methodology entails the rapid and comprehensive dispersion of CeO2 nanoparticles onto helical carbon nanocoils (CNCs), resulting in augmented electronic conductivity and an abundance of active sites within the composite. Consequently, the gas-sensing sensitivity of the nanocomposite at room temperature experienced a notable enhancement. Moreover, the presence of cerium oxide and the conversion of Ce3+ and Ce4+ ions facilitated the generation of oxygen vacancies in the composites, thereby further amplifying the sensing performance. Experimental outcomes demonstrate that the nanocomposite exhibited an approximate 9-fold increase in response to 50 ppm NO2 in comparison to pure CNCs at room temperature. Additionally, the CeO2/CNCs sensor displayed remarkable selectivity towards NO2 when exposed to gases such as NH3, CO, SO2, CO2, and C2H5OH. This straightforward microwave-solvothermal method presents an appealing strategy for the research and development of intelligent sensors based on CNCs nanomaterials.

Facile fabrication of binder-free carbon nanotube–carbon nanocoil hybrid films for anodes of lithium-ion batteries

Facile fabrication of binder-free carbon nanotube–carbon nanocoil hybrid films for anodes of lithium-ion batteries

Chiral structure induces spatial spiral arrangement of Fe3O4 nanoparticles to optimize electromagnetic wave dissipation

The spatial anisotropic arrangement of magnetic particles is expected to increase the magnetic resonance frequency of magnetic particles and optimize the magnetic loss. Herein, helical carbon nanocoils were used as a chiral template to induce the spatial spiral distribution of Fe3O4 particles. Meanwhile, a linear control group was constructed with carbon nanofibers as a template. The three-dimensional spiral structure promotes the confined growth and uniform distribution of Fe3O4 particles. Due to the enhanced magnetic property, chiral samples exhibited superior impedance matching compared to linear samples. Experimental tests and theoretical simulation confirm that the spatial anisotropic distribution helps to increase magnetic loss and optimize impedance matching. This work illustrates the important role of chiral structure in improving the magnetic anisotropy of magnetic nanoparticles and provides an effective strategy for optimizing electromagnetic wave dissipation.

Exploration of the role of oxygen-deficiencies coupled with Ni-doped V2O5 nanosheets anchored on carbon nanocoils for high-performance supercapacitor device

Electronic structural engineering via integration of oxygen deficiencies and a variety of dopants in metal oxide electrodes has fascinated the research interest for developing next-generation supercapacitors. Herein, by incorporating Ni dopants and creating O vacancies, it has thoroughly been explored the potential of vanadium oxide (V2O5) nanosheets anchored on the carbon nanocoils (CNCs) grown on nickel foam (NF) for supercapacitor electrodes (OV-Ni-V2O5/CNCs/NF). We validate a synergistic effect provided by heterostructure designed with multifunctional nano geometries. It is found that O vacancies and Ni dopants alter the electronic states of V2O5 with enhanced electrical conductivity and enriched redox active sites. We optimized O vacancies and achieved a specific capacity of 3485F g−1 (1742.5C g−1) at 1 A/g, representing ∼ 3.8 × higher compared to the best prior report. Furthermore, an asymmetric supercapacitor device was assembled with binder-free electrodes, using O0.075-V2O5/CNCs/NF as a cathode and sulfur-doped CNCs as an anode, which delivered a high energy density of 144 W h kg−1 and long-term stability of 5000 cycles, which is superior to most of the previous studies. This study paves a rational strategy to design high-performance electrodes for next-generation supercapacitors and other energy storage technologies.

1-D Carbon Nano-Coils Derived from Almond Skin: Exhibiting Density of State, Diffusivity, Electron Transfer Rate, and Dopamine Redox Modulation Properties Akin to Graphene Oxide.

The quest to develop graphene-like biomass-carbon for advanced biomolecule redox modulation and sensing remains a challenge. The primary obstacle is the limited ability of biomass to undergo extensive graphitization during pyrolysis resulting in the formation of amorphous carbon materials with a small carbon-double-bond-carbon domain size (Lsp2), density of state (LDOS), ion diffusivity (D), and electron transfer rate constant (Ks). Herein, using almond skin (AS) the morphology of biomass is demonstrated as the key to overcoming these limitations. AS consists of 1D syringyl/guaiacyl lignin nano-coils which under H2/H2 annealing transform into pyrolytic 1D carbon nano-coils (r-gC). Spectroscopy and microscopy analyses reveal that the sheet layering structure, crystallinity, LDOS, and Lsp2 of r-gC mimic those of graphene oxide (GO). Moreover, its unique 1D morphology and profound microstructure facilitate faster charge transfer and ion diffusion than GO's planar structure, leading to better redox modulation and sensing of the neurotransmitter dopamine (DA) in physiological fluids. r-gC's DA detection limit of 3.62nM is below the lower threshold found in humans and on par with the state-of-the-art. r-gC is also DA-selective over 14 biochemicals. This study reveals that biomasses with well-defined and compact lignin structures are best suited for developing highly electroactive graphene-like biomass carbon.

Porous Carbonaceous Aerogels Composed of Multiscale Carbon-Based Units for High-Performance Microwave Absorption.

Structural engineering is definitely a promising and effective approach to develop excellent microwave absorbing materials with quantities of advantages. Especially, when carbon materials act as the constituents, the fabricated absorbers are available to gain more prominent absorption performance. However, extra high conductivities and the widespread aggregations and stacking of low-dimensional carbon materials always detrimentally affect the impedance matching and weaken the attenuation capacity, inevitably confining their further absorption applications. Herein, by introducing the amorphous chiral carbon nanocoils to overcome the challenges and achieve the strategies of structure optimization and multicomponent recombination, the reduced graphene oxide/carbon nanocoil/carbon nanotube aerogels were successfully synthesized by a successive hydrothermal method and freeze-drying strategy. The as-obtained aerogels possess a porous architecture that contribute to the extraordinary impedance matching and multiple reflections, which integrate the multifarious dielectric loss mechanisms of diverse carbon materials simultaneously. Benefiting from the tricomponent synergistic effect, the ultralight aerogels reach an outstanding microwave absorption property with an extremely low filler content of only 6 wt %. This work provides a helpful approach to design hierarchical absorbers consisted by multidimensional carbon materials for fantastic microwave absorption.

Vibration and noise reduction for building floor structures based on new composite material vibration isolation pads

The frequent occurrence of geological disasters poses a significant threat to human life and the safety of property. To enhance the seismic performance and reduce noise in buildings, this study proposes the design of building floor structures with a new composite vibration isolation pad. Carbon nanocoils/styrene-butadiene composites are utilized to create vibration reduction devices. Experimental results demonstrate that the compression set rates of carbon nanocoil composite rubber are 4.83% and 2.07% at filling amounts of 1% and 3%, respectively. Additionally, the compression set rates of carbon nanotube composite rubber are 13.79% and 6.90%, respectively. Among these materials, styrene-butadiene exhibits the most significant performance improvement when combined with carbon nano coil. With an optimal layout of 25 devices, the floor dynamic amplification coefficient can be reduced by 8.4% and the building floor noise can be reduced by approximately 75%. This optimization significantly reduces the dynamic response and also provides a certain level of noise reduction effect.

Carbon Nanocoil-Based Photothermal Conversion Carrier for Microbubble Transport

Carbon nanocoil (CNC), a kind of quasi-one-dimensional carbon nanomaterial with a unique micro-scale helical structure, has wide application prospects in biological and environmental governance fields, due to its excellent photothermal conversion characteristics. We combine a carbon nanocoil as the laser irradiation carrier (i.e., the substance for absorbing light energy and converting light energy into heat to allow the creation of microbubbles) and a light-induced method to realize the radial short-distance transport of microbubbles. The results confirm that controlling the size of the microbubbles by laser power enables the radial transport of multiple microbubbles in a row. Light-induced CNC allows the creation of microbubbles at the start of the transport and the elimination of the microbubbles at the end of the transport, and the distance of transport between the laser irradiation site on the CNC and the location of the bubbles disappearing ranges from 10 µm to 30 µm. The circulation process of creating, transporting, and eliminating bubbles is expected to become a promising technology for soil and groundwater remediation.

Construction of chiral-magnetic-dielectric trinity composites for efficient microwave absorption with low filling ratio and thin thickness

The combination of carbon nanomaterials and magnetic nanomaterials has been proven to be a promising strategy to fabricate thin and lightweight microwave absorbers with tunable absorption bands and broadened bandwidth, especially the absorption capability in low frequency (2–10 GHz). Herein, a series of CoNi-based magnetic nanomaterials have been synthesized on the surfaces of chiral carbon nanocoils (CNCs) to form a chiral-magnetic-dielectric trinity composite through solvothermal reaction followed by a subsequent annealing method. The well-dispersed CoNi nanostructures enhance the magnetic loss of the composites, giving rise to the strong microwave absorption at low frequency. In addition, the dielectric CNCs with excellent chirality and dispersibility not only provide conduction loss and cross-polarization loss to broaden the absorption bandwidth, but also reduce the filling ratio of the composites. Accordingly, with the synergistic effect of the chiral-magnetic-dielectric components, combined with the good impedance and quarter-wavelength matchings, the trinity composite exhibits superior microwave absorption performance with a wide effective bandwidth of 6.1 GHz at the thickness of 1.85 mm. More importantly, the reflection loss value reaches −42 dB at 4.5 GHz with a low filling ratio of 12 wt%. This study provides a novel chiral-magnetic-dielectric trinity structure for highly efficient microwave absorption.

Hierarchical and Porous Structures of Carbon Nanotubes-Anchored MOF Derivatives Bridged by Carbon Nanocoils as Lightweight and Broadband Microwave Absorbers.

High-performance microwave absorption (MA) materials have attracted more and more attention because they can effectively prevent microwave radiation and interference from electronic devices. Herein, a new type of MA composite is constructed by introducing carbon nanotubes (CNTs)-anchored metal-organic framework derivatives (MOFDs) into a conductive carbonnanocoil (CNC) network, denoted as CNC/CNT-MOFD. The CNC/MOFD shows a wide effective absorption band of 6.7GHz under a filling ratio of only 9% in wax-matrix. This is attributed to the hierarchical and porous structures of MOFD bridged by the uniformly dispersed conductive CNC network and the cross-polarization induced by the 3D spiral CNCs. Besides, the as-grown 1D CNTs improve space utilization, porosity, and polarization loss of the composites, resulting in the increase of imaginary permittivity, which further realizes impedance matching and energy attenuation. The Ni nanoparticles in layers of MOFD and at the tips of CNTs generate magnetic loss, promoting the low-frequency absorption ability. Resultantly, RCS values of the optimized composite in all tested theta (θ) ranges are less than -25dB m2 at 9.5GHz, effectively reducing the probability of the target detected by the radar.

Ni3V2O8 Nanosheets Grafted on 3D Helical‐shaped Carbon Nanocoils as A Binder‐free Hierarchical Composite for Efficient Non‐enzymatic Glucose Sensing

AbstractHigh fabrication cost, chemical instability, and complex immobilization of enzyme molecules are critical issues of enzyme‐based glucose sensors. Designing state‐of‐the‐art, binder‐free, and non‐enzymatic glucose sensing probes plays an imperative role to cope with the aforementioned issues. 3D carbonaceous nanomaterials coated with transition metal vanadates (TMVs) are a favorable biomimetic platform for glucose quantification. Peculiar hierarchical structure, enhanced conductivity, synergistic interaction, multiple oxidation states, and high catalytic activity would make such composite a potential contender for non‐enzymatic glucose sensing. Herein, 3D helical‐shaped carbon nanocoils (CNCs) are grown on nickel foam (NF) via chemical vapor deposition method to prepare a robust CNCs/NF scaffold. Then, a hydrothermal route is followed to grow interconnected free‐standing Ni3V2O8 nanosheets (NSs) on CNCs/NF scaffold. This novel and binder‐free Ni3V2O8 NSs/CNCs/NF hierarchical composite possesses superior electrochemical active area (ECSA) and exceptional electrochemical efficacy. Amperometric analysis exhibits extremely prompt detection time (0.1 s), elevated sensitivity (5214 µA mM−1 cm−2), and low detection limit (0.04 µM). Developed sensor demonstrates appreciable recoveries (93.3 to 103.3%) regarding glucose concentration in human serum. The appealing analytical results show that deployment of a 3D helical‐shaped hierarchical smart scaffold can be an effective strategy for developing efficient and advanced non‐enzymatic glucose sensors.

Hybrid films constructed by carbon nanotubes and carbon nanocoils as current collectors for lithium-ion batteries

Lithium-ion batteries (LIBs) have attracted extensive attention in many fields but are still limited in application by capacity loss under long cycles. The poor contact between the current collector (CC) and active materials is one of the reasons that cause the energy attenuation of LIBs during long-term use. Herein, hybrid films constructed by mixing carbon nanotubes (CNTs) and carbon nanocoils (CNCs) through a simple vacuum filtration method are used as CCs for LIBs. It is found that the LIB using the film with a mass ratio of CNTs: CNCs = 3:1 shows the best performance, exhibiting a high capacity of 135.7 mAh g−1 at 5C, and stable cycling performance (>99% capacity retention) after 500 charge/discharge cycles at 1C. The excellent contact of active materials with the CNT-CNC hybrid film is achieved by the well-constructed CNC skeleton, making the CNTs more dispersed to form a uniform and interconnected structure. This work certifies that the CNT-CNC hybrid films are a promising candidate as CCs for high-performance LIBs.