Coaxial Wet Spinning of Boron Nitride Nanosheet‑Based Composite Fibers with Enhanced Thermal Conductivity and Mechanical Strength

Hexagonal boron nitride nanosheets(BNNSs)exhibit remarkable thermal and dielectric properties.However,their self-assembly and alignment in macroscopic forms remain challenging due to the chemical inertness of boron nitride,thereby limiting their performance in applications such as thermal management.In this study,we present a coaxial wet spinning approach for the fabrication of BNNSs/polymer composite fibers with high nanosheet orientation.The composite fibers were prepared using a superacid-based solvent system and showed a layered structure comprising an aramid core and an aramid/BNNSs sheath.Notably,the coaxial fibers exhibited significantly higher BNNSs alignment compared to uniaxial aramid/BNNSs fibers,primarily due to the additional compressive forces exerted at the core-sheath interface during the hot drawing process.With a BNNSs loading of 60 wt%,the resulting coaxial fibers showed exceptional properties,including an ultrahigh Herman orientation parameter of 0.81,thermal conductivity of 17.2 W m^(-1)K^(-1),and tensile strength of 192.5 MPa.These results surpassed those of uniaxial fibers and previously reported BNNSs composite fibers,making them highly suitable for applications such as wearable thermal management textiles.Our findings present a promising strategy for fabricating high-performance composite fibers based on BNNSs.

Rapid, high-efficient and scalable exfoliation of high-quality boron nitride nanosheets and their application in lithium-sulfur batteries

Boron nitride nanosheets(BNNSs)have gained significant attraction in energy and environment fields because of their two-dimensional(2D)nature,large band gap and high thermal/mechanical performance.However,the current low production efficiency of high-quality BNNSs is still a bottleneck limiting their applications.Herein,based on sonication-assisted liquid-phase exfoliation,we demonstrated a rapid,high-efficient and scalable production strategy of BNNSs and documented the effects of a spectrum of exfoliation factors(e.g.,ultrasonic condition,solvent and bulk material feeding)on the yield of BNNSs.A record of yield of 72.5%was achieved while the exfoliated BNNSs have few-layer and defect-free feature.Thanks to the Lewis acid sites of the boron atoms,the BNNSs can interact with the polysulfide anions in liquid electrolyte and also can facilitate the uniform lithium deposition,which finally endow a lithium-sulfur(Li-S)battery with long life.This work provides a facile and rapid strategy for large scale preparation of high-quality BNNSs,also contributes a long-life strategy for dendrite-free Li-S battery,opens new avenues of BNNSs in energy application.

Enhanced adsorption performance for antibiotics by alcohol-solvent mediated boron nitride nanosheets

The development of high-efficient adsorbents for the treatment of antibiotics from contaminated water has been of great concern.This work introduced an alcohol-solvent mediated strategy to increase the specific surface area(SSA)and porosity of hexagonal boron nitride nanosheets(BNNSs)for improving tetracycline(TC)removal efficiency.The BNNSs synthesized with the mediation of n-propanol solvent(BN-P)exhibited the largest pore volume and relatively high SSA(increased by 34%and 64%,respectively,compared with that synthesized under the mediation of water)in its structure,which in turn facilitated the mass transfer of TC molecules onto BN-P framework.The remarkable adsorption performance of BN-P,with 20%increase in equilibrium adsorption capacity and Langmuir maximum adsorption capacity of 556 mg·g^(-1),was achieved for capturing TC within just 3 h,which is mainly through p-p interaction and electrostatic force.Pseudo-second kinetics equation can well illustrate the adsorption process,while Freundlich and Langmuir isotherm models fitted the equilibrium data well.Thermodynamics study demonstrated a spontaneous exothermal adsorption process.Furthermore,the strong environmental suitability and notable recycling performance of BN-P revealed its good application prospect in removing antibiotic TC from wastewater.

The Effect of Polymer-Substrate Interaction on the Nucleation Property:Comparing Study of Graphene and Hexagonal Boron Nitride Nanosheets

Hexagonal boron nitride nanosheets （BNNSs） can work as a more efficient nucleating agent for two polyesters compared to graphene. Studies on the crystallization and dewetting processes of two polyesters, poly（butylene succinate） and poly（butylene adipate）, on the two substrate surfaces prove that the interaction between BNNSs and the polyesters is stronger than that between graphene and the polyesters. This strong interaction induces the pre-ordered conformation of molten PBA which has been identified by the in situ FTIR spectra. Thus BNNSs possess higher nucleation property than graphene. Finally, a new polymer-substrate interaction induced nucleation mechanism was proposed to explain the nucleation efficiency difference between graphene and BNNSs.

Facile and scalable preparation of ultra-large boron nitride nanosheets and their use for highly thermally conductive polymer composites

Due to their excellent physical and chemical properties,boron nitride nanosheets(BNNSs)have shown great application potential in many fields.However,the difficulty in scalable preparation of large-size BNNSs is still the current factor that limits this.Herein,a simple yet efficient microwave-assisted chemical exfoliation strategy is proposed to realize scalable preparation of BNNSs by using perchloric acid as the edge modifier and intercalation agent of h-BN.The as-obtained BNNSs behave a thin-layered structure(average thickness of 3.9 nm)with a high yield of~16%.Noteworthy,the size of BNNSs is maintained to the greatest extent so as to realize the preparation of BNNSs with ultra-large size(up to 7.1μm),which is the largest so far obtained for the top-down exfoliated BNNSs.Benefiting from the large size,it can significantly improve the thermal diffusion coefficient and the thermal conductivity of polyvinyl alcohol by 51 and 62 times respectively,both showing a higher value than the one previously reported.This demonstrates that the prepared BNNSs have great promise in enhancing the thermal conductivity of polymer materials.

Dielectric Properties of Multi-Layers Hexagonal Boron Nitride

A higher value of the dielectric constant of h-BN makes it quite favourable material in energy storing device. The variation in dielectric constant was observed as a function of thickness. In this research work multilayers of Hexagonal Boron Nitride (h-BN) was fabricated by using the Chemical exfoliation method. Two solvents Dimethylformamide (DMF) and Isopropyl Alcohol (IPA) were used for the exfoliation of h-BN. Successful sonication of hexagonal boron nitride led to the formation of Boron Nitride nanosheets (BNNs). The stable dispersibility of h-BN in Dimethylformamide and Isopropyl Alcohol was confirmed by UV Visible Spectroscopy, X-ray diffraction (XRD) and Scanning electron microscopy (SEM) confirm the mono crystallite structure (002) and nanoflakes like morphology of h-BN respectively. This appropriate strategy offered a feasible route to produce multilayer of hexagonal boron nitride. After the successful fabrication of h-BN multilayers its dielectric properties were calculated by using LCR meter. Profilometer revealed the variation in thickness and value of Dielectric constant was calculated by using its formula.

Flexible,Highly Thermally Conductive and Electrically Insulating Phase Change Materials for Advanced Thermal Management of 5G Base Stations and Thermoelectric Generators

Thermal management has become a crucial problem for high-power-density equipment and devices.Phase change materials(PCMs)have great prospects in thermal management applications because of their large capacity of heat storage and isothermal behavior during phase transition.However,low intrinsic thermal conductivity,ease of leakage,and lack of flexibility severely limit their applications.Solving one of these problems often comes at the expense of other performance of the PCMs.In this work,we report core–sheath structured phase change nanocomposites(PCNs)with an aligned and interconnected boron nitride nanosheet network by combining coaxial electrospinning,electrostatic spraying,and hot-pressing.The advanced PCN films exhibit an ultrahigh thermal conductivity of 28.3 W m^(-1)K^(-1)at a low BNNS loading(i.e.,32 wt%),which thereby endows the PCNs with high enthalpy(>101 J g^(-1)),outstanding ductility(>40%)and improved fire retardancy.Therefore,our core–sheath strategies successfully balance the trade-off between thermal conductivity,flexibility,and phase change enthalpy of PCMs.Further,the PCNs provide powerful cooling solutions on 5G base station chips and thermoelectric generators,displaying promising thermal management applications on high-power-density equipment and thermoelectric conversion devices.

A Bilayer High-Temperature Dielectric Film with Superior Breakdown Strength and Energy Storage Density

The further electrification of various fields in production and daily life makes it a topic worthy of exploration to improve the performance of capacitors for a long time,including thin-film capacitors.The discharge energy density of thin-film capacitors that serves as one of the important types directly depends on electric field strength and the dielectric constant of the insulation material.However,it has long been a great challenge to improve the breakdown strength and dielectric constant simultaneously.Considering that boron nitride nanosheets(BNNS)possess superior insulation and thermal conductivity owing to wide band gap and 2-dimensional structure,a bilayer polymer film is prepared via coating BNNS by solution casting on surface of polyethylene terephthalate(PET)films.By revealing the bandgap and insulating behavior with UV absorption spectrum,leakage current,and finite element calculation,it is manifested that nanocoating contributes to enhance the bandgap of polymer films,thereby suppressing the charge injection by redirecting their transport from electrodes.Worthy to note that an ultrahigh breakdown field strength(~736 MV m^(−1)),an excellent discharge energy density(~8.77 J cm^(−3))and a prominent charge-discharge efficiency(~96.51%)are achieved concurrently,which is ascribed to the contribution of BNNS ultrathin layer.In addition,the modified PET films also have superior comprehensive performance at high temperatures(~120°C).The materials and methods here selected are easily accessible and facile,which are suitable for large-scale roll-to-roll process production,and are of certain significance to explore the methods about film modification suitable for commercial promotion.

A Thermochromic, Viscoelastic Nacre-like Nanocomposite for the Smart Thermal Management of Planar Electronics

Cutting-edge heat spreaders for soft and planar electronics require not only high thermal conductivity and a certain degree of flexibility but also remarkable self-adhesion without thermal interface materials, elasticity, arbitrary elongation along with soft devices, and smart properties involving thermal self-healing, thermochromism and so on. Nacre-like composites with excellent in-plane heat dissipation are ideal as heat spreaders for thin and planar electronics. However, the intrinsically poor viscoelasticity, i.e., adhesion and elasticity, prevents them from simultaneous self-adhesion and arbitrary elongation along with current flexible devices as well as incurring high interfacial thermal impedance. In this paper, we propose a soft thermochromic composite(STC) membrane with a layered structure, considerable stretchability, high in-plane thermal conductivity(~30 Wm^(-1) K^(-1)), low thermal contact resistance(~12 mm^2 KW^(-1), 4–5 times lower than that of silver paste), strong yet sustainable adhesion forces(~4607 Jm^(-2), 2220 Jm^(-2) greater than that of epoxy paste) and self-healing efficiency. As a self-adhesive heat spreader, it implements efficient cooling of various soft electronics with a temperature drop of 20℃ than the polyimide case. In addition to its self-healing function, the chameleon-like behavior of STC facilitates temperature monitoring by the naked eye, hence enabling smart thermal management.

Enhancement of in-plane thermal conductivity of flexible boron nitride heat spreaders by micro/nanovoid filling using deformable liquid metal nanoparticles

With the fast development of integrated circuit devices as well as batteries with high energy densities,the thermal management of electronic components is becoming increasingly crucial to maintaining their reliable operations.Boron nitride nanosheets(BNNS),which have superhigh thermal conductivity along the in-plane direction while remaining electrically insulating,were widely regarded as an ideal filler for preparing high-performance polymer composites to address the‘‘thermal failure''issue.However,due to the instinctive rigidity of BNNS,the nanosheets are unable to form a tightly interfacial contact between the adjoining fillers,resulting in some micro-and nanovoids within the heat transfer pathways and severely limiting further thermal conductivity enhancement for BNNS-based composites.Herein,soft and deformable liquid metal(eutectic gallium-indium,EGaIn)nanoparticles were employed to fill the gaps between the adjacent BNNS with a rational design of mass ratios of BNNS and EGaIn,leading to a strongly synergistic effect with BNNS on thermal conductivity improvement.As a result,the composite film(BNNS:63 wt%and EGaIn:7 wt%)employing cellulose nanofibers(CNF:30 wt%)as the polymer matrix achieves superhigh thermal conductivity along the in-plane direction of up to(90.51±6.71)W·m^(-1)·K^(-1),showing the highest value among the BNNSbased composites with a bi-filler system as far as we know.Additionally,the film can work as a heat spreader for the heat dissipation of high-power light emitting diodes,outperforming tin foil in cooling efficiency.

Superinsulating BNNS/PVA Composite Aerogels with High Solar Reflectance for Energy-Efficient Buildings

With the mandate of worldwide carbon neutralization,pursuing comfortable living environment while consuming less energy is an enticing and unavoidable choice.Novel composite aerogels with super thermal insulation and high sunlight reflection are developed for energy-efficient buildings.A solvent-assisted freeze-casting strategy is used to produce boron nitride nanosheet/polyvinyl alcohol(BNNS/PVA)composite aerogels with a tailored alignment channel structure.The effects of acetone and BNNS fillers on microstructures and multifunctional properties of aerogels are investigated.The acetone in the PVA suspension enlarges the cell walls to suppress the shrinkage,giving rise to a lower density and a higher porosity,accompanied with much diminished heat conduction throughout the whole product.The addition of BNNS fillers creates whiskers in place of disconnected transverse ligaments between adjacent cell walls,further ameliorating the thermal insulation transverse to the cell wall direction.The resultant BNNS/PVA aerogel delivers an ultralow thermal conductivity of 23.5 mW m^(−1) K^(−1) in the transverse direction.The superinsulating aerogel presents both an infrared stealthy capability and a high solar reflectance of 93.8%over the whole sunlight wave-length,far outperforming commercial expanded polystyrene foams with reflective coatings.The anisotropic BNNS/PVA composite aerogel presents great potential for application in energy-saving buildings.

High Conduction Band Inorganic Layers for Distinct Enhancement of Electrical Energy Storage in Polymer Nanocomposites

Dielectric polymer nanocomposites are considered as one of the most promising candidates for high-power-density electrical energy storage applications.Inorganic nanofillers with high insulation property are frequently introduced into fluoropolymer to improve its breakdown strength and energy storage capability.Normally,inorganic nanofillers are thought to introducing traps into polymer matrix to suppress leakage current.However,how these nanofillers effect the leakage current is still unclear.Meanwhile,high dopant(>5 vol%)is prerequisite for distinctly improved energy storage performance,which severely deteriorates the processing and mechanical property of polymer nanocomposites,hence brings high technical complication and cost.Herein,boron nitride nanosheet(BNNS)layers are utilized for substantially improving the electrical energy storage capability of polyvinylidene fluoride(PVDF)nanocomposite.Results reveal that the high conduction band minimum of BNNS produces energy barrier at the interface of adjacent layers,preventing the electron in PVDF from passing through inorganic layers,leading to suppressed leakage current and superior breakdown strength.Accompanied by improved Young’s modulus(from 1.2 GPa of PVDF to 1.6 GPa of nanocomposite),significantly boosted discharged energy density(14.3 J cm^(-3)) and charge-discharge efficiency(75%)are realized in multilayered nanocomposites,which are 340 and 300% of PVDF(4.2 J cm^(-3),25%).More importantly,thus remarkably boosted energy storage performance is accomplished by marginal BNNS.This work offers a new paradigm for developing dielectric nanocomposites with advanced energy storage performance.

Defect‐rich BN‐supported Cu with superior dispersion for ethanol conversion to aldehyde and hydrogen

Copper‐based heterogeneous catalysts commonly exhibit uncontrolled growth of copper species under reaction conditions because of the low Hüttig temperature(surface mobility of atoms)and Tamman temperature(bulk mobility)for copper at just 134 and 405°C,respectively.Herein,we report the use of defect‐enriched hexagonal boron nitride nanosheets(BNSs)as a support to anchor the Cu species,which resulted in superior dispersion of the Cu species.The obtained Cu/BNS catalyst was highly stable for ethanol dehydrogenation,with a high selectivity of 98%for producing acetaldehyde and an exceptionally high acetaldehyde productivity of 7.33 g_(AcH) g_(cat)^(‒1) h^(‒1) under a weight hourly space velocity of 9.6 g_(EtOH) g_(cat)^(‒1) h^(‒1).The overall performance of our designed catalyst far exceeded that of most reported heterogeneous catalysts in terms of the stability of the Cu species and the yield of acetaldehyde in this reaction.The hydroxyl groups at the defect edges of BNS were responsible for the stabilization of the copper species,and the metal‐support interaction was reinforced through charge transfer,as evidenced by coupling atomic resolution images with probe molecule infrared spectroscopy and X‐ray photoelectron spectroscopy.A designed in situ diffuse reflectance infrared Fourier transform spectroscopy study of ethanol/acetaldehyde adsorption further revealed that Cu/BNS favored ethanol adsorption while suppressing acetaldehyde adsorption and further side reactions.This study demonstrates a new method for designing highly dispersed Cu‐based catalysts with high durability.

Chemical adsorption on 2D dielectric nanosheets for matrix free nanocomposites with ultrahigh electrical energy storage

Relaxor ferroelectric polymers display great potential in capacitor dielectric applications because of their excellent flexibility,light weight,and high dielectric constant.However,their electrical energy storage capacity is limited by their high conduction losses and low dielectric strength,which primarily originates from the impact-ionization-induced electron multiplication,low mechanical modulus,and low thermal conductivity of the dielectric polymers.Here a matrix free strategy is developed to effectively suppress electron multiplication effects and to enhance mechanical modulus and thermal conductivity of a dielectric polymer,which involves the chemical adsorption of an electron barrier layer on boron nitride nanosheet surfaces by chemically adsorbing an amino-containing polymer.A dramatic decrease of leakage current(from 2.4×10^(-6)to 1.1×10^(-7)A cm^(-2)at 100 MV m^(-1))and a substantial increase of breakdown strength(from 340 to 742 MV m^(-1))were achieved in the nanocompostes,which result in a remarkable increase of discharge energy density(from 5.2 to 31.8 J cm^(-3)).Moreover,the dielectric strength of the nanocomposites suffering an electrical breakdown could be restored to 88%of the original value.This study demonstrates a rational design for fabricating dielectric polymer nanocomposites with greatly enhanced electric energy storage capacity.

Design of B/N Co-doped micro/meso porous carbon electrodes from CNF/BNNS/ZIF-8 nanocomposites for advanced supercapacitors

Boron(B)and nitrogen(N)co-doped 3D hierarchical micro/meso porous carbon(BNPC)were successfully fabricated from cellulose nanofiber(CNF)/boron nitride nanosheets(BNNS)/zinc-methylimidazolate framework-8(ZIF-8)nanocomposites prepared by 2D BNNS,ZIF-8 nanoparticles,and wheat straw based CNFs.Herein,CNF/ZIF-8 acts as versatile skeleton and imparts partial N dopant into porous carbon structure,while the introduced BNNS can help strengthen the hierarchical porous superstructure and endow abundant B/N co-dopants within BNPC matrix.The obtained BNPC electrode possesses a high specific surface area of 505.4 m2/g,high B/N co-doping content,and desirable hydrophilicity.Supercapacitors assembled with BNPC-2(B/N co-doped porous carbon with a CNF/BNNS mass ratio of 1꞉2)electrodes exhibited exceptional electrochemical performance,demonstrating high capacitance stability even after 5000 charge-discharge cycles.The devices exhibited outstanding energy density and power density,as well as the highest specific capacitance of 433.4 F/g at 1.0 A/g,when compared with other similar reports.This study proposes a facile and sustainable strategy for efficiently fabrication of rich B/N co-doped hierarchical micro/meso porous carbon electrodes from agricultural waste biomass for advanced supercapacitor performance.

Nacre-bionic nanocomposite membrane for efficient in-plane dissipation heat harvest under high temperature

Waste heat management holds great promise to create a sustainable and energy-efficient society as well as contributes to the alleviation of global warming.Harvesting and converting this waste heat in order to improve the efficiency is a major challenge.Here we report biomimetic nacre-like hydroxyl-functionalized boron nitride(BN)-polyimide(PI)nanocomposite membranes as efficient 2D in-plane heat conductor to dissipate and convert waste heat at high temperature.The hierarchically layered nanostructured membrane with oriented BN nanosheets gives rise to a very large anisotropy in heat transport properties,with a high in-plane thermal conductivity(TC)of 51 Wm^(-1) K^(-1) at a temperature of~300 C,7314%higher than that of the pure polymer.The membrane also exhibits superior thermal stability and fire resistance,enabling its workability in a hot environment.In addition to cooling conventional exothermic electronics,the large TC enables the membrane as a thin and 2D anisotropic heat sink to generate a large temperature gradient in a thermoelectric module(△T=23 ℃)through effective heat diffusion on the cold side under 220 C heating.The waste heat under high temperature is therefore efficiently harvested and converted to power electronics,thus saving more thermal energy by largely decreasing consumption.

Avoiding heating interference and guided thermal conduction in stretchable devices using thermal conductive composite islands

The miniaturization and high integration of devices demand significant thermal management materials.Current technologies for the thermal management of electronics show some limitations in the case of multiple chip arrays.A device in multiple chip array is affected by heat from adjacent devices,along with thermal conductive composite.To address this problem,we present a nano composite of aligned boron nitride(BN)nanosheet islands with porous polydimethylsiloxane(PDMS)foam to have mechanical stability and non-thermal interference.The islands of tetrahedrally-structured BN in the composite have a high thermal conductivity of 1.219 W·m^(-1)·K^(-1) in the through-plane direction(11.234W·m^(-1)·K^(-1)in the in-plane direction)with 16 wt.%loading of BN.On the other hand,porous PDMS foam has a low thermal conductivity of 0.0328W·m^(-1)·K^(-1) in the through-plane direction at 70%porosity.Heat pathways are then formed only in the structured BN islands of the composite.The porous PDMS foam can be applied as a thermal barrier between structured BN islands to inhibit thermal interference in multiple device arrays.Furthermore,this composite can maintain selective thermal dissipation performance with 70%tensile strain.Another beauty of the work is that it could have guided heat dissipation by assembling of multiple layers which have high vertical thermal conductive islands,while inhibiting thermal interference.The selective heat dissipating composite can be applied as a heatsink for multiple chip arrays electronics.

Flexible, high sensitive and radiation-resistant pressure-sensing hydrogel

Excellent radiation resistance is a prerequisite for pressure-sensitive hydrogels to be used in high-energy radiation environments. In this work, tannic acid-modified boron nitride nanosheet(BNNS-TA) is first prepared as the radiation-resistant additive by a facile one-step ball milling of hexagonal boron nitride and tannic acid. Then, polyacrylamide(PAAm)-based pressure-sensitive hydrogel doped with BNNS-TA and Fe^(3+)ions is fabricated. The ternary BNNS-TA/Fe^(3+)/PAAm hydrogel exhibits excellent compressive strength(at least four times the compressive strength of unfilled pure PAAm hydrogel), pressure-sensitive performance(gauge factor is up to 1.4), and performance recovery due to the combination of multiple intermolecular interactions, such as covalent crosslinking, hydrogen bonds, and ion coordination interactions.The BNNS-TA/Fe^(3+)/PAAm hydrogel can be made as a pressure sensor installed in the control circuit or attached on the human body to detect human activities accurately. More importantly, the compressive strength and the pressure-sensitive performance of the BNNS-TA/Fe^(3+)/PAAm hydrogel can be maintained after the hydrogel is irradiated by^(60)Co gamma-ray at an absorbed dose of 15 k Gy. As a comparison, the compressive strength of the unfilled PAAm hydrogel is only a quarter of that before irradiation. This work not only reveals a facile method to achieve the preparation of chemically modified BNNS as a promising radiation-resistant additive but also provides a novel strategy for the development of pressure-sensitive hydrogel devices in radiation environments.

One-step exfoliation and deprotonation of ANF/BNNS suspension for constructing 3D vertically aligned skeleton in epoxy-based thermal management composites

Two-dimensional(2D)boron nitride nanosheet(BNNS)is promising in polymer-based thermal management materials(TMMs)by pre-constructing three-dimensional(3D)thermally conductive skeleton,but it yet suffers from the challenges of higheffective exfoliation and affinitive compatibility with matrix.In this work,we developed a one-step exfoliation and deprotonation approach by the high-effective ball milling technique to prepare aramid nanofiber(ANF)/BNNS suspension.Under the strong collision/shear effect of ball-milling,micron-level h BN sheets were exfoliated into smaller and thinner BNNS with edge functional groups,meanwhile,poly-p-phenylene terephthalamide(PPTA)fibers were split into ANF by dissociating the intermolecular hydrogen bonds.More importantly,both the exfoliation and deprotonation could be accelerated by each other to achieve a 100%yield of ANF/BNNS suspension with strong hydrogen/covalent bonding interactions between them.Subsequently,the prepared ANF/BNNS suspension was used to construct 3D vertically aligned ANF/BNNS skeleton by the unidirectional freezing method.The obtained epoxy-based composite(EP/ANF/BNNS)revealed excellent thermal conductivity of 2.41 W m^(-1)K^(-1) at 14.9 vol%BNNS loading due to the vertically oriented heat conduction paths and low interfacial thermal resistance in the skeleton.Moreover,EP/ANF/BNNS composite showed high thermal stability and extraordinary fire retardancy with dramatically decreased heat release rate(265 W g^(-1)) and total heat release(20.6 kJ g^(-1)).Therefore,this work demonstrates a high-efficient one-step ball-milling exfoliation and deprotonation technique for preparing ANF/BNNS suspension,which reveals an enormous potential in preparing advanced TMMs by constructing 3D thermally conductive skeletons.