Intrinsic Thermal Conductivity Research Articles

MXene grafted porous carbon cloth with alumina for high thermal conductivity and EMI shielding effect

Thermal interface material (TIM) has a great potential for efficient heat management and safety of electronic devices. However, achieving high performance polymer-based TIM is still challenging because of its intrinsic thermal conductivity and weak mechanical properties. In particular, electromagnetic interference shielding effect (EMI SE) of polymer-based composites has a great attraction according to electronic devices have become ubiquitous, playing integral roles in everyday life in our increasingly interconnected world. Herein, a porous carbon cloth (CC) for use as a continuous thermally and electrically conductive template is prepared via a freeze-casting method, after which mxene (MX) is chemically grafted onto the CC surface. Then, the as-prepared MX-CC is used along with alumina (AO) to fill a poly vinyl alcohol (PVA) matrix in order to fabricate a thermally conductive film with electromagnetic interference (EMI) shielding properties. The resultant composite demonstrates remarkable characteristics, including an excellent EMI shielding effect of 28 dB, substantial tensile strength of 19 MPa, and impressive out of plane thermal conductivity (3.98 W/mK). When applied to a light-emitting diode (LED), the PVA/MX-CC/AO composite effectively manages heat, thereby resulting in a 49 °C reduction in the operating temperature. Therefore, the composites developed herein hold great promise for improving thermal management in electronic devices.

High Thermal Conductive Liquid Crystal Elastomer Nanofibers.

Liquid crystal elastomers (LCEs), consisting of polymer networks and liquid crystal mesogens, show a reversible phase change under thermal stimuli. However, the kinetic performance is limited by the inherently low thermal conductivity of the polymers. Transforming amorphous bulk into a fiber enhances thermal conductivity through the alignment of polymer chains. Challenges are present due to their rigid networks, while cross-links are crucial for deformation. Here, we employ hydrodynamic alignment to orient the LCE domains assisted by controlled in situ cross-linking and to remarkably reduce the diameter to submicrons. We report that the intrinsic thermal conductivity of LCE fibers at room temperature reaches 1.44 ± 0.32 W/m-K with the sub-100 nm diameter close to the upper limit determined in the quasi-1D regime. Combining the outstanding thermal conductivity and thin diameters, we anticipate these fibers to exhibit a rapid response and high force output in thermomechanical systems. The fabrication method is expected to apply to other cross-linked polymers.

Thermal Conductivity of the Graphene/Polydimethylsiloxane Composite by Manipulating the Network Structure.

In this work, a nonequilibrium molecular dynamics simulation is utilized to explore the effect of network structure of graphene (GE) on the thermal conductivity of the GE/polydimethylsiloxane (PDMS) composite. First, the thermal conductivity of composites rises with increasing volume fraction of GE. The heat transfer ability via the GE channel is found to be nearly the same by analyzing the GE-GE interfacial thermal resistance (ITR). More heat energy is transferred via the GE channel at the high volume fraction of GE by calculating the GE heat transfer ratio, which leads to the high thermal conductivity. Then, the thermal conductivity of composites rises with increasing stacking area between GE, which is attributed to both the strong heat transfer ability via the GE channel and the high GE heat transfer ratio. Following it, the thermal conductivity of composites first rises and then drops down with increasing defect density for a single vacancy defect while it continuously increases for a single void defect. The heat transfer ability between GE is enhanced due to the formation of interlayer covalent bonds. However, the intrinsic thermal conductivity of GE is significantly reduced for a single vacancy defect while it remains relatively well for a single void defect. As a result, the GE heat transfer ratio is maximum at the intermediate defect density for a single vacancy defect while it rises monotonically for a single void defect, which can rationalize the thermal conductivity. Meanwhile, the relationship between ITR and the number of covalent bonds can be described by an empirical equation. Finally, the thermal conductivity for the stacked structure is larger than that for the noncontact structure or the intersected structure. In summary, this work provides a clear and novel understanding of how the network structure of GE influences the thermal conductivity of the GE/PDMS composite.

Influence of microscopic ordered arrangement and high-voltage directional molding in epoxy liquid crystal dispersed membranes on intrinsic thermal conductivity

Flexible epoxy liquid crystal dispersed membranes (ELCMs) with high thermal conductivity (TC) were successfully prepared by using high-voltage directional molding. Epoxy liquid crystal monomers (Epoxy-LC1 and Epoxy-LC2) were uniformly dispersed into flexible epoxy polymers cured by pentaerythritol tetra (3-mercaptopropionate). TC of ELCM1 and ELCM2 reached 1.27 W·(m·K)−1 and 2.36 W·(m·K)−1 with 30 wt% content of Epoxy-LC1 and Epoxy-LC2, which were 4.5 times and 8.43 times higher than that of pure epoxy polymer, respectively. Tensile strength and elongation at break of ELCM1 and ELCM2 were up to 8.1 MPa, 23 % and 23.8 MPa, 46.7 %, respectively. On the one hand, the favorable results are attributed to the molecular chains’ microscopic ordered arrangement by using high-voltage directional molding. On the other hand, the more important reason is that the hydrogen-bond interactions between −C=O and –OH of molecular chains in Epoxy-LC2 and epoxy polymer. This work offers a new way to design flexible epoxy resins and intrinsic thermal conductive polymers.

Flexible composite films with ultrahigh through-plane thermal conductivity yet low graphene content

Graphene-based polymeric composites have become one of the promising thermal interface materials (TIMs) for the high integration electronic devices due to the excellent intrinsic thermal conductivity of graphene. However, the challenges still remain, such as ordered alignment of graphene in elastic polymer and regulation of phonon scattering at graphene/graphene interface. In this study, a vertically oriented graphene framework within a flexible silicone rubber matrix was fabricated by non-solvent induced phase separation (NIPs) coupled with an in in-situ welding technique. The as-prepared film exhibits an outstanding through-plane thermal conductivity of 29.5W/mK at low graphene loading of 7.5 wt%, which indicates an exceptionally high thermal conductivity enhancement per 1 wt% graphene content (specific TCE) over 1950 %/wt%. Furthermore, the composite films demonstrate excellent conformability inherited from the silicone rubber matrix and achieves low contact resistance of 40–70 Kmm2W−1 under various pressure and interfacial conditions. This study contributes to a deeper insight into the development of the high-performance graphene-based polymeric TIMs.

Flexible hexagonal boron nitride@liquid metal/polydimethylsiloxane composites with excellent thermal conductivity and superior mechanical properties

AbstractHexagonal boron nitride (h‐BN) has a layered lattice structure, high intrinsic thermal conductivity, and good chemical stability, and it has a promising applications in thermal management materials. However, poor interfacial compatibility and dispersion of BN flakes in the polymer matrix cause thermal contact resistance and gaps, directly impairing the performance of the composites and limiting their thermal conduction applications. Herein, the P‐BN@LM/PDMS thermally conductive composites with superior mechanical properties were fabricated by incorporating dopamine and liquid metal (LM) into BN flakes. The dopamine self‐polymerizes to form polydopamine (PDA) on the BN surface, denoted as P‐BN, which effectively improves interface compatibility and dispersion. The LM attaches to the functionalized P‐BN surface by mechanical grinding, acting as a bridge between adjacent BN flakes to enhance the integrity of the thermal conductive network within the composites. The coordination between P‐BN and LM increases interface strength, effectively improving mechanical performance. Hence, the P‐BN@LM/PDMS composites exhibit excellent thermal conductivity (4.0 W/mK) and an enhancement factor of 1373%, which is 2.22 times that of BN/PDMS composites with the same 30 wt% loading. Additionally, the composite shows superior tensile strength (2.11 MPa) and elongation at break (121%), representing 441% and 203% improvements compared with pure polydimethylsiloxane (PDMS). The P‐BN@LM/PDMS composites, with significant advantages in thermal conductivity and mechanical properties, are promising for future applications as flexible thermal interface materials in thermal management.Highlights The P‐BN@LM/PDMS composites exhibit excellent thermal conductivity (4.0 W/mK) and an enhancement factor of 1373%, making them promising for future applications as flexible thermal interface materials in thermal management. The P‐BN@LM/PDMS composites present a superior tensile strength (2.11 MPa) and elongation at break (121%). PDA formed by the self‐polymerization of dopamine on the BN surface effectively enhances interfacial compatibility and dispersion. LM attaches to the functionalized BN surface through mechanical grinding, acting as a bridge between adjacent BN flakes, thus enhancing the integrity of the thermal conductive network within the composites.

Improving thermoelectric properties in double half-Heusler M8FexNi8−xSb8 (M = TiZrHfNb)-InSb compounds via synergistic multiscale defects and high-mobility carrier injection

In this study, the modulation doping strategy combined with atomic-scale engineering is applied to the Double half-Heusler (DHH) system. Thermoelectric properties of multi-principal-element alloy Ti2Zr2Hf2Nb2FexNi8−xSb8 are first improved through composition optimization and then modulation doping with nano-InSb. First-principles calculations indicate that strong phonon anharmonicity results in low intrinsic lattice thermal conductivity (κL). Synergistic high-mobility carrier injection and multiscale defects caused by lattice distortion, sluggish diffusion effect, and inhomogeneous doping decouple electron and phonon transport that extrinsically intensified phonon scattering and optimized carrier transport. Consequently, the ZTmax values of nano-InSb doped p-type (x = 5.6) and n-type (x = 2.4) samples are 0.6 and 0.36, respectively, which increased by 663 % and 350 %, compared with the InSb-free x = 5 sample. The corresponding κL near room temperature are as low as ∼2.7 and ∼2.3 W m−1 K−1, respectively. Furthermore, the p-type composition exhibits a relatively high power factor (∼2 mW m−1 K−2), and the n-type samples show negligible bipolar effects at high temperatures. This work provides a novel strategy for the optimization of thermoelectric properties in DHH compounds.

Enhanced intrinsic thermal conductivity of liquid crystalline polyester dispersed films through hydrogen bond interaction

Polymer-dispersed liquid crystal (MHxFy) films comprising liquid crystal polymer (LCPH and LCPF) were successfully obtained by the method of solution casting & thermal compressing. At a LCPH mass fraction of 67 %, thermal conductivity (λ) value in through-plane (λ⊥) and in-plane (λ∥) direction of MH2F1 films reach up to 0.305 W/(m·K) and 2.879 W/(m·K), respectively. In comparison to pure LCPF, the thermal conductivity of MH2F1 exhibited an increase of 4.42 times, which is 14.4 times than that of conventional thermoplastics. Meanwhile, the crystallinity of MHxFy films around 50 % which is indicate the crystal phase become more integrated and regular. The FTIR spectra reveals a significant blue shift (3432 cm−1 to 3421 cm−1) in the absorption peak of the –OH group in MH2F1, suggesting a robust interaction between LCPF and LCPH. The primary cause of elevated thermal conduction in these films was determined to be the consistent presence of “thermal bridges” and a high degree of crystallinity. Furthermore, the T5%, Tmax and residual carbon at 800 °C of MH2F1 were 347.8 °C, 409.4 °C and 8 %, respectively. This is attributed to the ordered distribution of LCPH in LCPF matrix through hydrogen bonding interaction, forming an interpenetrating network of LCPF-LCPH. The result show that MHxFy films demonstrating superior intrinsic thermal conductivities, thermal stabilities, and mechanical properties.

First-principles calculations of structural and bonding properties of Li-doped tetrahedrite thermoelectrics

Tetrahedrite (copper antimony sulfosalt) is a promising p-type thermoelectric material due to its very low intrinsic thermal conductivity and moderately-high power factor, with one of the limitations being the lack of n-type variant to create a thermoelectric generator. In this paper, DFT calculations have been carried out to study tetrahedrite doped with Li into structural voids, LixCu12Sb4S13 (0≤x≤3). Enthalpies of formation show that the introduction of Li into both 6b and 24 g sites is energetically favorable. Dopants in those positions differently affect the rattling Cu(12e) behavior, as well as vary in the magnitude of induced local disorder. Topological analysis of charge density classifies tetrahedrite as a closed-shell, ionic system of interactions with some degree of covalency. The addition of Li increases bond strain and decreases structural stability. Electronic band structure shows that for x>2.0, material becomes n-type; however, results are not precisely conclusive on whether structure will be synthesizable, which should be determined experimentally.

Anisotropic thermally conductive films based on two‐dimensional nanomaterials

AbstractThe significant advancement of high‐power densification and miniaturization in modern electronic devices has attracted increasing attention to effective thermal management. The primary objective of thermal management is to transfer excess heat from electronics to the outside environment through the use of thermal conductive materials. The anisotropic thermally conductive films (TCFs) based on two‐dimensional (2D) nanomaterials exhibit outstanding controlled heat transfer capability, which effectively removes hotspots along the in‐plane direction and provides thermal insulation along the cross‐plane direction. However, a comprehensive review of anisotropic TCFs is rarely reported. Herein, we first discuss the intrinsic anisotropic thermal conductivity of 2D nanomaterials for preparing TCFs. Then, the preparation methods and anisotropic thermal conductivity of TCFs have been summarized and discussed. Furthermore, we conclude with the practical applications of TCFs for anisotropy thermal management. Finally, a conclusion of the challenges and outlook of TCFs is provided to promote their development in future scientific research.

Development of High Performance Thermoelectric Polymers via Doping or Dedoping Engineering.

It is of great significance to develop high-performance thermoelectric (TE) materials, because they can be used to harvest waste heat into electricity and there is abundant waste heat on earth. The conventional TE materials are inorganic semimetals or semiconductors like Bi2Te3 and its derivatives. However, they have problems of high cost, scarce/toxic elements, high thermal conductivity, and poor mechanical flexibility. Organic TE materials emerged as the next-generation TE materials because of their merits including solution processability, low cost, abundant element, low intrinsic thermal conductivity, and high mechanical flexibility. Organic TE materials are mainly conducting polymers because of their high conductivity. Both the conductivity and Seebeck coefficient depend on the doping level, and they are interdependent. Hence, the TE properties of polymers can be improved through doping/dedoping engineering. There are three types of doping forms, oxidative (or reductive) doping, protonic acid doping, and charge transfer doping. Accordingly, they can be dedoped by different approaches. In this article, we review the methods to dope and dedope p-type and n-type TE polymers and the combination of doping and dedoping to optimize their TE properties. Secondary doping is also covered, since it can significantly enhance the conductivity of some TE polymers.

Magnetically assembled flexible phase change composites with vertically aligned structures for thermal management and electromagnetic interference shielding

Phase change material (PCM) is promising in achieving zero-energy thermal management because of its prominent thermal storage capacity and steady phase-change temperature. However, low intrinsic thermal conductivity (TC), liquid leak, and solid rigidity are long-standing bottlenecks for heat-related applications. Here, we report an innovative dual-encapsulation strategy to develop multifunctional phase change composite (FMP) with vertically aligned NdFeB@Ag arrays and styrene-ethylene-propylene-styrene (SEPS) crosslinked network in paraffin (PA). The NdFeB@Ag arrays induced by magnetic-field driven procedure can offer the consecutive/oriented highways for efficient heat-transfer, and an electric/magnetic heterostructure for electromagnetic interference shielding efficiency (EMI SE). The flexible SEPS block copolymer not only ensures the high flexibility of PCM, but also combines with oriented NdFeB@Ag arrays for dual encapsulating PA. This multifunctional FMP can achieve high TC of 2.59 W m−1 K−1, attractive EMI SE of 35.42 dB, prominent enthalpy density of 120 J g−1, and impressive Joule heating performance, together with leakage-proof, dynamic assembly, and salient charging/discharging durability. Furthermore, the FMP-supported device is demonstrated for thermal energy harvesting and utilization. This dual-encapsulation design opens a new avenue for exploiting multifunctional PCMs for thermal management, anti-EM radiation, and low-grade exhaust heat utilization.

Modulating cross-linked network structure of epoxy resin blends towards concurrently high intrinsic thermal conductivity and dielectric properties

Modulating cross-linked network structure of epoxy resin blends towards concurrently high intrinsic thermal conductivity and dielectric properties

Mechanically strong, healable, and recyclable supramolecular solid–solid phase change materials with high thermal conductivity for thermal energy storage

Conventional polymeric solid–solid phase change materials (SSPCMs) have garnered significant attention in the development of state-of-the-art latent heat storage (LHS) systems. However, the industrial application of polymeric SSPCMs is compromised by inferior mechanical properties and intrinsic low thermal conductivity. In addition, they are unable to be recycled and self-healed due to permanently cross-linked structures. In this study, a series of healable and recyclable supramolecular SSPCMs (PEG4K-Bx-PEG6K), possessing robust tensile strength (∼22.90 MPa), excellent strain-at-break (∼733.62 %), and high toughness (∼120.05 MJ/m3), are designed and developed by incorporating dynamic boroxines and hydrogen bonds. Because of the reversibility of dynamic boroxines and hydrogen bonds, the PEG4K-Bx-PEG6K was able to be healable and conveniently processed into packaging bag. More importantly, the PEG4K-Bx-PEG6K also possessed high thermal storage capacity (98.03 J/g), and excellent thermal shape memory capability. To achieve efficient heat transfer, an orientated solar thermal composite with high thermal conductivity was fabricated by compression-induced repetitive stacking of oriented graphene nanosheets (GNs) layers in PEG4K-Bx-PEG6K. Thanks to the efficient heat conduction of oriented GNs layers in the composite, the directional thermal conductivity of composite was up to 3.639 W/mK at 5 wt% loading of GNs. Combining the above excellent heat conduction, the solar thermal composite developed in this work offered efficient solar thermal conversion, fast transportation and storage of the harvested thermal energy.

Advanced rare earth tantalate RETaO4 (RE=Dy, Gd and Sm) with excellent oxygen/thermal barrier performance

Thermal barrier coatings (TBCs) materials with lowered thermal and oxygen ion conductivity can provide thermal and oxidative protection for high temperature hot-end components in aeronautical engines and gas turbines. The rare-earth tantalate RETaO4 (RE = Dy, Gd and Sm) ceramics with monoclinic (m) phase were successfully synthesized via spark plasma sintering. Oxygen vacancies responsible for the thermal and oxygen ion conductivities of RETaO4 were demonstrated by atomic-resolution energy dispersive X-ray and X-ray photoelectron spectroscopy. Among the three samples, DyTaO4 has excellent oxygen/thermal barrier performance. Compared to the current service thermal barrier coating material ZrO2-8 wt% Y2O3 (8 YSZ), DyTaO4 has an ultra-low oxygen ion conductivity benefiting from low oxygen vacancy concentration and strong stretching force constants. The intrinsic thermal conductivity of DyTaO4 is 68.2% less than that of 8 YSZ. Additionally, the thermal expansion rate curves indicate that the phase transformation does not happen from room temperature to 1200 °C. The above results demonstrate that high-growth rate thermally grown oxide can be retarded by creating dense DyTaO4 coating with lowered thermal and oxygen ion conductivity.

Directional thermal transport feature in binary filler-based SiR composites with horizontally oriented h-BN

Efficiently thermal management in electronic devices calls for creating polymer composites that have superior thermal transport abilities. Compared with single-filler composites, hybrid-filler composites have gained significant attention as they not only utilize the advantages of each filler individually but also allow for the potential cooperation in constructing filler networks between them. Differing from the previous research on hybrid-filler size, geometry, composition, and content and their impact on thermal conductivity (TC) in composites, this study aims to examine the spatial distribution effects of hybrid-fillers. A binary-filler strategy comprising of anisotropic 2D h-BN and 0D isotropic S–Al2O3 has been proposed, with the primary h-BN filler aligned to filly utilize its anisotropy and intrinsic TC properties. Furthermore, positioning a small quantity of S–Al2O3 between adjacent parallel h-BN considerably improves TC in the non-oriented direction of silicon rubber (SiR) composites. A special focus is given to the influence of the interstitial S–Al2O3 filler on the individual through-plane TC (λ⊥) and in-plane TC (λ⫽) variation of the binary-filler hybrid SiR composites, which are perpendicular and parallel to the oriented h-BN. When incorporating 40 vol% h-BN and 5 vol% S–Al2O3, the binary SiR composites exhibit the highest concurrent λ⫽ and λ⊥ values of 14.581 and 2.132 W/m·K, respectively. The corresponding effects on the ductility, hardness, and dielectric properties of the SiR composites were explained. Moreover, the use of commercially available TC fillers, along with the effortless preparation method, enables the potential to produce h-BN based TIMs materials on a large scale for thermal management usage.

Enhancing thermal conductance between graphene and epoxy interfaces through non-covalent cation-π interactions

Although graphene has high thermal conductivity, its application in thermal management remains challenging because of the large interfacial thermal resistance between graphene and adjacent materials. This work demonstrates that non-covalent cationic-π interaction can significantly improve the thermal conductance between graphene and substrate interfaces. Cationic polyacrylamide (CPAM) bridges substrate and graphene with hydrogen bonding and cation-π interaction, respectively. The cation-π interaction between graphene and CPAM is confirmed by Raman, UV–Vis and NMR spectroscopy. The results show that CPAM increases the interfacial adhesion of graphene/epoxy from 18.7 ± 2.2 mN to 37.4 ± 7.6 mN (100.0 % improvement) and improves the interfacial thermal conductivity (ITC) from 22 ± 2 MW/m2K to 51 ± 5 MW/m2K (131.8 % improvement). Enhancing the ITC of graphene/epoxy by introducing CPAM assembled layer has advantages over covalent modifications because it provides a similar level of ITC improvement rate, but has little effect on the intrinsic thermal conductivity of graphene. Finally, it is demonstrated that the sample with graphene/cationic polyelectrolyte/substrate structure exhibits great potential for applications in the area of thermal management and printed circuit boards.

One Stone Two Birds: Anomalously Enhancing the Cross‐Plane and In‐Plane Heat Transfer in 2D/3D Heterostructures by Defects Engineering

AbstractThis study addresses a crucial challenge in two‐dimensional (2D) material‐based electronic devices—inefficient heat dissipation across the van der Waals (vdW) interface connecting the 2D material to its three‐dimensional (3D) substrate. The objective is to enhance the interfacial thermal conductance (ITC) of 2D/3D heterostructures without compromising the intrinsic thermal conductivities (κ) of 2D materials. Using 2D‐MoS2/3D‐GaN as an example, a novel strategy to enhance both the ITC across 2D/3D interface and κ of 2D material is proposed by introducing a controlled concentration (ρ) of vacancy defects to substrate's bottom surface. Molecular dynamics simulations demonstrate a notable 2.1‐fold higher ITC of MoS2/GaN at ρ = 4% compared to the no‐defective counterpart, along with an impressive 56% enhancement in κ of MoS2 compared to the conventional upper surface modification approaches. Phonon dynamics analysis attributes the ITC enhancement to increased phonon coupling between MoS2 and GaN, resulting from polarization conversion and hybridization of phonons at the defective surface. Spectral energy density analysis affirms that the improved κ of MoS2 directly results from the proposed strategy, effectively reducing phonon scattering at the interface. This work provides an effective approach for enhancing heat transfer in 2D/3D vdW heterostructures, promisingly advancing electronics’ heat dissipation.

Thermophysical characterization and reliability analysis of binary composite nano doping on stearic acid-acetamide eutectic PCM

Organic phase change materials (PCM) have been extensively studied and employed for thermal energy storage applications, especially in the last decade. Wide range of melting temperature with high latent heat of fusion and absence of super cooling have made them highly desirable for energy storage applications, yet their intrinsic low thermal conductivity has been a major drawback in practical implementation. This study intends to address this and study the thermophysical characteristics of an organic PCM through composite nano doping. Stearic acid-acetamide eutectic PCM with a melting temperature of 65.73 °C and a latent heat of 203.72 J/g, was incorporated with a binary blend of Aluminum Oxide nanoparticles and multi-walled carbon nanotubes (MWCNT). The addition of metallic oxide and carbonaceous nanoparticles increased the melting temperature of the eutectic mixture by 2.9 °C and a highly advantageous increment in latent heat of fusion by 10% was observed, due to the improved molecular interaction introduced by the nanoparticles. Composite nano doping enhanced the thermal conductivity of the eutectic PCM by a 132.7% and also resulted in high optical absorption properties. The prepared eutectic mixtures were chemically stable and the eutectic PCM showed an improved final degradation temperature and thermal stability, with composite nano doping. Thermal reliability was analyzed through accelerated thermal cycling test and the eutectic mixtures could retain their thermal characteristics and chemical stability even after 500 thermal cycles. Composite nano doping proved to be a reliable thermophysical characteristics enhancement technique for organic eutectic PCM.

Simultaneous measurement of thermal conductivity and emissivity of micro/nanomaterials

Although thermal conductivity of micro/nano scale material has been readily measured, the high specific surface area leads to non-negligible radiative heat transfer. Here, a method for simultaneous measurement of intrinsic thermal conductivity and emissivity of micro/nano materials was developed and verified. The physical model of this measurement principle consisted of two parallel platinum wires, which serve as both heaters and heat flux meters. Thermal conductivity and emissivity can be derived by comparing the changes in the average temperature rise of the heater and sensor platinum wires before and after attaching the test sample. The thermal conductivity and emissivity of an individual platinum wire were determined to 71.7 W/(m·K) and 0.14, which are consistent with the reference values. Subsequently, the thermal conductivity and emissivity of the polymer composite fiber were measured to be 1.45 W/(m·K), 0.73 and 1.87 W/(m·K), 0.8 at different composite filler concentrations. In principle, this method is applicable for accurately measuring the thermal transport properties of any micro/nano wires using appropriate sensors.