Uniform Carbon Shell Research Articles

Three-dimensional MoS2 nanosheets embeded within NiTe nanorods forming semicoherent heterojunctions achieving high-performance potassium-ion batteries

Three-dimensional MoS2 nanosheets uniformly embedded within NiTe nanorods are synthesized via one-step hydrothermal method and subsequently coated with a carbon layer to form stable NiTe@MoS2@C heterojunctions. The heterojunctions exhibit moderate lattice mismatch (δ =20.0 %), strong electric fields, and uniform carbon shells, resulting in unique electronic configurations and abundant active sites. As an anode for potassium-ion batteries, NiTe@MoS2@C demonstrated an high reversible capacity of 258.4 mAh g−1 after 100 cycles at a rate of 200 mA g−1. Moreover, it showed a stable reversible capacity of 177.5 mAh g−1 at a high rate of 5000 mA g−1, indicating excellent rate performance. Notably, even in the NiTe@MoS2@C//perylene tetracarboxylic dianhydride full battery configuration, a significant reversible capacity of 87.4 mAh g−1 was maintained after 100 cycles at a rate of 200 mA g−1, manifesting its remarkable potential for practical applications in potassium-ion batteries. Theoretical calculations further revealed that the well-designed NiTe@MoS2 heterojunction significantly enhances K+ ion diffusion.

Rational design of a setaria-like NiTe2/MoS2 semi-coherent heterogeneous interface for enhancing diffusion kinetics in potassium-ion batteries

Constructing unique heterostructures is a highly effective approach for enhancing the K+ storage capability of transition metal selenides. Such structures generate internal electric fields that significantly reduce the charge transfer activation energy. However, achieving a flawless interfacial region that maintains the optimal energy level gradient and degree of lattice matching remains a considerable challenge. In this study, we synthesised Setaria-like NiTe2/MoS2@C heterogeneous interfaces at which three-dimensional MoS2 nanosheets are evenly embedded in NiTe2 nanorods to form stabilised heterojunctions. The NiTe2/MoS2 heterojunctions display distinctive electronic configurations and several active sites owing to their low lattice misfits (δ = 13 %), strong electric fields, and uniform carbon shells. A NiTe2/MoS2@C anode in a potassium-ion battery (KIB) exhibited an impressive reversible capacity of 125.8 mAh/g after 1000 cycles at a rate of 500 mA g−1 and a stable reversible capacity of 111.7 mAh/g even after 3000 cycles at 1000 mA g−1. Even the NiTe2/MoS2@C//perylene tetracarboxylic dianhydride full battery configuration maintained a significant reversible capacity of 92.4 mAh/g after 100 cycles at 200 mA g−1, highlighting its considerable potential for application in KIBs. Calculations further revealed that the well-designed NiTe2/MoS2 heterojunction significantly promotes K+ ion diffusion.

Efficient Ionic Conductor Anode Materials with Heterojunction Structure of MnOx/Si@C Utilized in Lithium‐Ion Batteries

AbstractThe rapid development of alternative energy vehicles has raised higher requirements for electrode materials. Silicon, with superhigh specific capacity, is highly anticipated in the field of lithium‐ion batteries (LIBs). Unfortunately, the original drawbacks of serious volumetric effect and poor conductivity have confined its commercial steps severely. Herein, a novel composite, based on submicron silicon flakes embedded into carbon shell, with heterojunction‐bearing MnOx nanoparticles, is designed and synthesized successfully via sanding process and in situ thermal reduction methods. The results of electrochemical performance tests and related fitting data show that the presence of MnOx particles facilitates rapid Li+ transport and reduces the impedance associated with Li+ diffusion from the surface to the inner core of the MnOx/Si@C material. The two‐dimensional (2D) silicon flakes and uniform carbon shell have positive influence on structural stability and electronic conductivity. Benefit from the rational design, the optimized MnOx/Si@C composite delivers an outstanding cycling stability of 1106.59 mAh·g−1 at 1 A·g−1 over 1000 cycles with a capacity retention of 71.09%. Besides, the goal material possesses a lithium‐ion diffusion coefficient of ≈1.04×10−9 cm2·s−1. This work provides a reference for the mass preparation of advanced anode materials for lithium‐ion batteries.

PDDA coating method on surface of catalyst to form carbon shell for enhancing durability of polymer electrolyte membrane fuel cells

Construction of a physical protective layer on the catalyst surface of platinum-based catalysts in fuel cells to increase their durability has attracted attention of researchers. In particular, the carbon shell is suitable as a coating material because it covers relatively few active sites of Pt compared to other coating materials. However, the conventional carbon shell formation method is complex, time-consuming, and does not form a uniform layer easily. In this study, a new method for attaching a poly(diallyldimethylammonium chloride)(PDDA) polymer to the catalyst surface and forming a carbon shell through heat treatment was proposed. This method can easily forms a thin and uniform carbon shell with a thickness of ≤1 nm, minimizes performance reduction, and maintains superior durability of catalyst. For the 120-h single cell durability test, the current density at 0.6 V and maximum power density of Pt/C without carbon shell decreased by 32.3 % and 26.5 %, respectively, compared to the initial performance, whereas it was confirmed that 5.9 % and 9.0 % were reduced, respectively, in the case of carbon-shelled Pt/C manufactured in this study. This new method of carbon shell formation is expected to be easily applicable to various nanoparticle-based catalysts that require a physical protective layer to ensure durability.

Urchin-like Fe3O4@C hollow spheres with core–shell structure: Controllable synthesis and microwave absorption

The steadily increasing use of microwave stealth materials in aerospace flying vehicles needs the development of lightweight absorbers with low density and high thermal stability for printing or spraying. In that regard, the structural designability of typical microwave absorbers made of Fe3O4 seems to be a significant roadmap. In this work, a hollow spherical structure with a uniform carbon shell around the urchin-like Fe3O4 core (Fe3O4@C) was produced via a two-step hydrothermal method and annealing. The Fe3O4@C absorber exhibited a strong minimum reflection loss (RLmin) of −73.5 dB at the matching thickness of 3.23 mm. The maximum effective absorption bandwidth (EABmax) was 4.78 GHz at 4.55 mm. The proposed urchin-like core–shell structure was shown to provide good impedance matching and electromagnetic loss ability due to the synergistic effect of Fe3O4 and C. In particular, the urchin-like structure increases the heterogeneous interfaces and effectively improves their polarization and relaxation. On the other hand, it reduces the density of the absorber and enhances multiple scattering attenuations of electromagnetic waves (EMWs). Therefore, the findings of the present study open up prospects for the design of high-efficiency lightweight microwave absorbers with specialized structures.

Constructing triple-protected Si/SiOx@ZnO@C anode derived from volatile silicon waste for enhanced lithium storage capacity

Silicon anode is deemed to be one of the most promising anode materials and has attracted wide attention from all walks of life. However, its commercial application is severely limited owing to the high cost, serious volume expansion, and poor electrical conductivity. Herein, Si/SiOx nanoparticles were successfully prepared by sand milling the low-cost volatile deposited silicon waste from electron beam refining polycrystalline silicon. Furthermore, the atomic layer deposited (ALD) zine oxide on Si/SiOx nanoparticles enhances the integrity of the electrode structure and provides a steady solid electrolyte layer (SEI). The outer layer is wrapped by a uniform carbon shell to restrict the volume expansion and boost the conductivity of the electrode during lithiation/delithiation. Impressively, lithium-ion batteries (LIBs) employing the Si/SiOx@ZnO@C anodes display excellent rate performance (up to 844.48 mAh g−1 at 2 A g−1) and cycle stability (912.7 mAh g−1 at 1A g−1 over 50 cycles). Moreover, the Si/SiOx@ZnO@C electrode exhibits high initial coulombic efficiency (76.8 %) and the reversible specific capacity maintains at 846 mAh g−1 over 200 cycles with a current density at 0.5 A g−1. The improvement is ascribed to the synergistic effect of triple-protected layer that effectively enhances the stability of SEI and the conductivity of the electrode. This work not only opens a novel and economic strategy for the manufacture of high-performance silicon-based anode but also furnishes an original approach for recycling and resource utilization of silicon waste.

Two Birds with One Stone: Concurrent Ligand Removal and Carbon Encapsulation Decipher Thickness-Dependent Catalytic Activity.

A carbon shell encapsulating a transition metal-based core has emerged as an intriguing type of catalyst structure, but the effect of the shell thickness on the catalytic properties of the buried components is not well known. Here, we present a proof-of-concept study to reveal the thickness effect by carbonizing the isotropic and homogeneous oleylamine (OAm) ligands that cover colloidal MoS2. A thermal treatment turns OAm into a uniform carbon shell, while the size of MoS2 monolayers remains identical. When evaluated toward an acidic hydrogen evolution reaction, the calcined MoS2 catalysts deliver a volcano-type activity trend that depends on the calcination temperature. Rutherford backscattering spectrometry and depth-profiling X-ray photoelectron spectroscopy consistently provide an accurate quantification of the carbon shell thickness. The same variation pattern of catalytic activity and carbon shell thickness, aided by kinetic studies, is then persuasively justified by the respective limitations of electron and proton conductivities on the two branches of the volcano curve.

In situ F doping-induced multilayer FeS2@CoS@C hierarchical heterostructures for ultrafast lithium storage

In this work, via in situ F doping induction, multilayer hierarchical heterostructures of FeS2@CoS encapsulated with carbon shell (F-FeS2@CoS@C) were rationally designed for lithium-ion batteries. Strongly synergistic coupling interactions among the F-FeS2@CoS and CoS@C interface accelerated electron and ion migration throughout the F-FeS2@CoS@C nanorods. The uniform carbon shell relieved volume expansion and maintained structural stability during the lithiation/delithiation process. In addition, the hierarchical heterostructures of FeS2@CoS@C and introduction of F atoms further improved electrical conductivity and provided more active sites to heighten electrochemical reaction kinetics. As a result, the F-FeS2@CoS@C nanorods delivered a good rate performance (633 mAh/g at 5.0 A/g) and stable long-cyclic performance of 597.1 mAh/g at 2.0 A/g after 800 cycles with the capacity retention ratio of 83.6%. The strategy of constructing hierarchical heterostructures via heteroatomic doping will be beneficial to design novel electrode materials for alkali metal ion batteries.

Graphitic carbon-wrapped iron nanoparticles derived from a melamine-modified metal-organic framework as efficient Friedel-Crafts acylation catalysts

Developing efficient heterogeneous catalysts for Friedel-Crafts acylation (FCA) reactions is highly attractive for its wide application in green synthesis and biomass conversion. Herein, a series of graphitic carbon-wrapped iron nanoparticles (Fe/C-x, x refers to the heat temperature ranged from 500 to 800 °C) were prepared through pyrolysis of a metal-organic framework (MOF) precursor of Fe-TPA-Mel, synthesized from iron salt, terephthalic acid (TPA) and melamine (Mel). The resultant Fe/C-600 catalyst exhibited excellent catalytic activity for the acylation of aromatic compounds with acyl chlorides, and better recyclability than the reference catalyst of Fe/C-600-ref derived from the Fe-TPA precursor. Various characterization results demonstrated that introducing melamine in the MOF precursor is beneficial for the formation of graphitic carbon-wrapped Fe nanoparticles at relatively low pyrolysis temperature, although the N species existed in the precursor of Fe-TPA-Mel could be nearly completed removed during the pyrolysis process. The relatively uniform graphitic carbon shell could provide an effective protection for the inside active iron species, finally resulting in the generation of stable and easily recycled heterogeneous FCA catalysts.

Monodisperse core-shell Li4Ti5O12@C submicron particles as high-rate anode materials for lithium-ion batteries

Monodisperse spinel Li4Ti5O12 (LTO) particles coated with a carbon layer (LTO@C) are prepared by using a solid-phase sintering reaction between pre-synthesized carbon-coated TiO2 particles and lithium carbonate. The core-shell structured LTO@C particles have an average size of about 320 nm, and a carbon shell thickness of about 10 nm. While the TiO2 particles that are pre-coated with a carbon layer generate LTO@C particles with monodisperse un-aggregated morphology, the TiO2 particles without carbon coating eventually lead to aggregated LTO particles with an irregular morphology. Much better rate performances are observed for LTO@C particles than the un-coated LTO particles. The discharge specific capacity of the typical LTO@C sample is about 165.5 mAh g−1 at 0.1 C and 147.7 mAh g−1 at 20 C. The discharge specific capacity still keeps at 133.6 mAh g−1 after 200 cycles. The results demonstrate that the presence of carbon shell on the surface of TiO2 particles can prevent the particle agglomeration and limit the growth of lithium titanate grains within the space of carbon shell, and finally generate monodisperse un-aggregated morphology which can increase the contact area between the active material and the electrolyte. Furthermore, the uniform carbon shell can establish a conductive network to improve the overall electronic conductivity, which is beneficial to the improvement of the rate performances of LTO anodes for the applications of lithium-ion batteries.

Highly robust, transparent, and conductive films based on AgNW-C nanowires for flexible smart windows

Flexible transparent conductive films (FTCFs) have attracted tremendous concern because it is a key component of next generation electronics and optoelectronic devices. Silver nanowires (AgNWs) random networks have become the most promising candidates for FTCFs, with high transmittance, low sheet resistance, and excellent mechanical flexibility. However, there are many barriers to the application of FTCFs based on AgNWs, such as easy oxidization and weak adhesion to the substrates. Here, we developed a facile approach to fabricate AgNW-C core–shell nanowires derived from the carbonization of glucose by a one-pot solvothermal method. A uniform amorphous carbon shell coating improves the chemical stability of AgNWs and the hydroxyls on the surface of the nanowires enhance the adhesion to the substrate. The AgNW-C/poly(ethylene terephthalate) (PET) transparent conductive film shows excellent robustness when subjected to bending (ΔR/R0 ≈ 2.8% after bending 2000 times). Besides, the conductivity of AgNW-C/PET film remains relatively stable after 100 peeling-off cycles by a 3 M tape test. A flexible electrochromic device (FCD) has also been constructed based on the AgNW-C/PET film, which shows promising stability and mechanical flexibility due to the remarkable electrochemical stability and mechanical strength of the AgNW-C/PET films. The results present the significant potential applications of the flexible transparent device based on AgNW-C/PET film for many fields in the future.

A surface-engineering-assisted method to synthesize recycled silicon-based anodes with a uniform carbon shell-protective layer for lithium-ion batteries

Yolk-shell silicon/carbon composite encapsulated by uniform carbon shell (Si@C) are becoming an effective method to mitigate volume-related issues of Si-based anodes and maintain an excellent performance for lithium-ion batteries (LIBs). However, a uniform carbon shell in Si@C is difficult to guarantee. Herein, a facile surface-engineering-assisted strategy is described to prepare Si@C composite with low-cost modified recycled waste silicon powders (RWSi) as core coated by a uniform carbon shell-protective layer derived from the pyrolysis of poly (methyl methacrylate) (PMMA) as carbon source (m-RWSi@PMMA-C). In this process, surface-engineering is performed with silane coupling agent kh550 to functionalize the RWSi particles via a silanization reaction, guaranteeing a uniform PMMA coating which will be transformed into carbon shell-protective layer after carbonization. The m-RWSi@PMMA-C electrode delivers an optimal discharge capacity of 1083 mAhg−1 at 200 mAg−1 after 200 cycles with an initial capacity of 3176.2 mAhg−1 and a high initial Coulombic efficiency (ICE) of 75.6%. Based on these results, the recycled silicon-based anode with a uniform carbon shell-protective layer displays great application potential and it also brings a new perspective on silicon-based anodes via surface-engineering method for LIBs.

Construction of CoP@C embedded into N/S-co-doped porous carbon sheets for superior lithium and sodium storage

To improve the electrical conductivity and relief the large volume variation, carbon coated CoP particles were designed to homogeneously embed into porous carbon sheets, which were synthesized though a simultaneous carbonization and phosphorization method. Notably, the uniform carbon shells and porous carbon sheets constructed a tough conductive matrix to enhance the electron transfer and structural stability during charging/discharging processes. Moreover, the heteroatom doping of nitrogen and sulfur could not only introduce more active sites and defects on the carbon sheets, but also increased electrical conductivity. Owing to the unique structure, the obtained material displayed good electrochemical performance for lithium storage (638.8 mA h g−1 at 0.2 A g−1 after 500 cycles and 334.9 mA h g−1 at 10 A g−1) and sodium storage (329.4 mA h g−1 at 0.2 A g−1 after 150 cycles and 162.4 mA h g−1 at 5 A g−1). More importantly, the reaction mechanism and the ion diffusion coefficient were explored by ex-situ XRD and EIS for both LIBs and SIBs. This versatile approach may avail to predigest the tedious phosphating process to obtain high-performance TMPs-based hybrids (such as Ni2P/C) by employing other metal salts.

Stabilizing conversion reaction electrodes by MOF derived N-doped carbon shell for highly reversible lithium storage

Surface engineering has been applied to resolve the problem of cycling instability in conversion/alloying reaction electrodes which can have high capacity but suffer from large volumetric change and pulverization in electrochemical cycles. However, due to structural instability, most of the surface coatings are still fragile and unstable in electrochemical cycles. Here, a facile low-temperature melting method has been developed to fabricate a uniform and ultrathin metal-organic framework (MOF) shell on various oxides electrode materials, followed by a gradient heat treatment process. A uniform and ultrathin N-doped carbon (NC) shell is formed as a robust coating to keep the integrity of materials and provide a highly conductive pathway for both electron and ions. This carbon confinement strategy can be easily applied to diverse ternary metal oxides with high bonding energy, such as Zn 2 SiO 4 , Zn 2 WO 4 and Zn 2 TiO 4. The obtained carbon-confined Zn 2 SiO 4 (Zn 2 SiO 4 @NC) nanowires have achieved enhanced lithium storage performances compared to pure Zn 2 SiO 4 nanowires. As revealed by in situ transmission electron microscopy, in the process of lithiation the Zn 2 SiO 4 @NC nanowires have lower radical expansion and faster kinetics than pure Zn 2 SiO 4 nanowires, and the N-doped carbon shell remains stable. This work provides a new approach for the design and construction of carbon-based nanostructures which have great potential in energy-related applications. A general method for fabricating a strong coating layer of N-doped-carbon to confine target nanostructures has been developed via a facile and efficient low temperature melting method of forming metal-organic framework (MOF) and subsequent controlled pyrolysis, to boost the cycling stability of electrode materials run on conversion/alloying reactions for lithium-ion battery. • A low-temperature melting method is developed to fabricate a robust MOF derived N-doped carbon shell as a uniform coating for oxides. • The carbon-confined Zn2SiO4 nanowires exhibit enhanced lithium storage performance compared to pure Zn2SiO4 nanowires. • In situ transmission electron microscopy has revealed that the N-doped carbon shell remains intact in lithiation. • The carbon-confined Zn2SiO4 nanowires have lower radical expansion and faster kinetics than pure Zn2SiO4 nanowires.

Synthesis of Bi2S3/C yolk-shell composite based on sulfur impregnation for efficient sodium storage

Bismuth sulfide (Bi2S3) is considered as an attractive anode material for sodium-ion battery (SIB) systems owing to its high theoretical capacity (625 mAh g−1) and laminar structure for storing host ions. However, capacity fading due to the large volume change during long term cycling is a serious problem preventing the practical application of this material to SIBs. Also, its electrical conductivity is still unsatisfactory. To solve those problems, the design of a Bi2S3/C composite with a yolk-shell type structure is proposed. The synthesis method of Bi2S3/C yolk-shell composite includes the fabrication of Bi/C yolk-shell platforms followed by a simple sulfur-impregnation step to obtain Bi2S3/C yolk-shell composites. This sulfur-impregnation step does not result in any degradation of the particle structure and preserves the uniform carbon shell. Furthermore, the Bi2S3/C yolks-shell composite displays enhanced electrochemical performance as an SIB anode material and exhibits high stability during long-term cycling (282.4 mAh g−1 after 300 cycles at 0.2C) and improved rate capability (413.0 mAh g−1 at 10C). These improvements are mainly attributed to the conductive electron pathway provided by the carbon shell and the suppression of large volume changes due to the presence of voids in the yolk-shell structure.

A facile synthesis of carbon-encapsulated ZnFe2O4 nanocrystals as anode for lithium-ion batteries

An explosive reaction between zinc nitrate hexahydrate and ferrocene taking place below 200∘C is discovered, which is employed for the one-step preparation of carbon-encapsulated ZnFe2O4 nanocrystals (ZnFe2O4@C) with core–shell structure in an autoclave. The small-sized equiaxed ZnFe2O4 nanocrystals have a median diameter of 22.1[Formula: see text]nm. The uniform carbon shell of about 5[Formula: see text]nm in thickness is amorphous, and its content is 32.6[Formula: see text]wt.% in the nanocomposite. After 50 cycles, the ZnFe2O4@C anode still maintains a high specific capacity of 551[Formula: see text]mAh[Formula: see text]g[Formula: see text] at a current density of 50[Formula: see text]mA[Formula: see text]g[Formula: see text]. The efficient, energy-saving and environment-friendly method will be very attractive for preparing different kinds of carbon-encapsulated nanocrystals.

Three-dimensional, hetero-structured, Cu3P@C nanosheets with excellent cycling stability as Na-ion battery anode material

A novel flower-like superstructure consisting of single-crystalline Cu3P porous nanosheets wrapped by a uniform carbon shell exhibits excellent electrochemical performance for sodium storage.

One-pot co-precipitation synthesis of Fe3O4 nanoparticles embedded in 3D carbonaceous matrix as anode for lithium ion batteries

Fe3O4@C nanoparticles with a 3D net-like structure were synthesized via a facile and scalable one-pot co-precipitation followed by a subsequent carbonization in an Ar atmosphere. Verified by scanning and transmission electron microscopy characterization, it can be seen that Fe3O4 nanoparticles with the size of 10–15 nm were embedded in a uniform carbon shell with a thickness of around 2 nm. Furthermore, the corresponding XRD and EDS analysis combined with TEM images also proved that the thin carbon layer on the nano-scale Fe3O4 was amorphous. The charge/discharge tests showed that Fe3O4@C composite delivered an excellent reversible capacity of 980 mAh g−1 after 100 cycles at a current density of 92.4 mA g−1, which was much higher than that of the pure Fe3O4 (170 mAh g−1) synthesized by the same method. The outstanding reversible capacity is attributed to the small size of Fe3O4 particles and the high conductivity and mechanical strength of the amorphous carbon layer, which accelerates the electron transfer and relieves structure collapse caused by mechanical stress, thus maintaining a superior electrochemical stability.

One-step fabrication of in situ carbon-coated NiCo2O4@C bilayered hybrid nanostructural arrays as free-standing anode for high-performance lithium-ion batteries

Rapid developments in revolutionary electric vehicles have led to an increase in the energy-density and cycling-life requirements for Li-ion batteries (LIBs). The binary transition metal oxide NiCo2O4 is attracting considerable attention due to its much larger specific capacity than graphite. However, NiCo2O4 suffers from poor cycling performance owing to a large volume change during cycling. To address this problem, we proposed an easy strategy to fabricate in situ carbon-coated NiCo2O4 bilayered hybrid nanostructural arrays supported on Ni foam (denoted as NiCo2O4@C BHNAs–NF) as free-standing anodes for LIBs through a sucrose-assisted hydrothermal method. The in situ-synthesized uniform carbon shell can simultaneously buffer the volume change during cycling and increase the conductivity. The micro/nano-structure also possessed outstanding structural advantages, such as large surface area and hierarchical porous characters, enabling NiCo2O4@C BHNAs–NF to have excellent electrochemical performance. Its capacity can reach 1298 mAh/g at a current density of 100 mA/g, and 86% of the initial capacity can be retained after 100 cycles. All these results revealed that NiCo2O4@C BHNAs–NF was a promising candidate anode for next-generation LIBs.

Largely enhanced dielectric constant of PVDF nanocomposites through a core-shell strategy.

Core-shell structured TiO2@carbon nanowire (TiO2@C NW) hybrids with different carbon shell thicknesses were synthesized by a combination of a hydrothermal reaction and the chemical vapor deposition (CVD) method. Pristine TiO2 NWs with a high aspect ratio were obtained by a hydrothermal reaction and the as-synthesized TiO2 NWs were subsequently employed as the template for carbon shell deposition during the CVD procedure. The obtained TiO2@C NW hybrids have a uniform carbon shell and the thickness of the carbon shell could be precisely designed from 4 nm to 40 nm by controlling the deposition time. With the help of solution and melt blending methods, the TiO2@C NW hybrids were subsequently incorporated into the PVDF matrix to fabricate TiO2@C NWs/PVDF nanocomposites, which exhibit a similar percolative dielectric behavior to that reported in other percolative nanocomposites. Moreover, the dielectric properties of the TiO2@C NWs/PVDF nanocomposites could be accurately adjusted by tuning the carbon shell thickness of the TiO2@C NW hybrids. The highest dielectric constant (2171) of the TiO2@C NWs/PVDF nanocomposites is 80 times larger than those of the pristine TiO2-filled ones at the same filler loading, and 241 times higher than that of the pure PVDF matrix. The enhanced dielectric performance could be attributed to the improved interfacial polarizations of TiO2/C and C/PVDF interfaces. This approach provides an interesting alternative to fabricate high-performance dielectric nanocomposites for practical applications in the electronic industry.