Thermal Conductivity Resistance Research Articles

Numerical and thermal resistance analysis on the cryogenic porous medium heat exchanger with liquid channel

The porous medium heat exchanger has been increasingly utilized in cryogenic applications, especially in the milli-Kelvin region. This study focuses on the porous medium heat exchanger with liquid channel commonly used in the dilution refrigerator and proposes a numerical model, which applies the local thermal non-equilibrium (LTNE) model coupled with N–S equations and Brinkman-Forchheimer model. Comparing with literature results validates the numerical model. By analyzing the heat transfer characteristics of the heat exchanger, a thermal resistance network model is developed to capture the heat transfer mechanism. The results show that the total thermal resistance mainly depends on the fluid conductive thermal resistance and Kapitza thermal resistance inside the porous medium. The fluid conductive thermal resistance dominates at higher temperature while the Kapitza thermal resistance dominates at lower temperature. The expression of critical temperature is derived to determine the priority of reducing thermal resistance. At cryogenic temperatures, the porous medium serves to bypass the significant Kapitza thermal resistance by introducing much lower thermal resistances, while at normal temperatures, the porous medium reduces the overall thermal resistance by incorporating a parallel thermal resistance but without magnitude difference.

Strategy for a high thermal conductivity and low thermal resistance under compression of oriented carbon fiber with spherical alumina thermal interface material

Thermal pads prepared with pitch-based carbon fibre (CF) orientation have garnered widespread attention due to their generally higher through-plane thermal conductivity. However, these thermal pads must undergo compression during the assembly process. When the compression exceeds a certain threshold, the orientation degree of the CFs inside the thermal pad can change, leading to a reduction in thermal conductivity. In this study, spherical alumina and CF were utilized to optimize thermal transfer stability under compression. The results demonstrate that the composites can still maintain efficient and stable heat transfer even when compressed by 25 %, which represents a more than 60 % improvement compared to pure CF-oriented composites. Furthermore, the relative motion between spherical alumina and CF, driven by their significant morphological differences, enhances the degree of CF orientation during the orientation process. With only 11.8 wt% CF loading, the composite achieved an impressive through-plane thermal conductivity of up to 20.4 W·m−1·K−1.

Upgrading the dynamic mathematical model of temperature sensors in gaseous media for low Biot number (Bi < 0.1)

A mathematical model incorporating the transient response of NTC thermistors is presented. The internal thermal conduction resistance of the sensor relative to the thermal convection resistance of the medium results in a low Biot number Bi<0.1, yielding a fast dynamic response in gaseous media. This is advantageous in applications requiring minimal fluid interaction. However, negligible energy exchanges occur, introducing measurement uncertainty and ignoring the behavior of the measuring instrument. Therefore, this work proposes an improvement strategy for the mathematical model of these sensors, complementing the conventional model based on the concept of time constant. The strategy considers the heat flow through the thermistor wires in the energy balance, assuming they are semi-infinite solids and applying an approximation to the heat flow formula. Satisfactory improvement results were obtained compared to the conventional model, based on controlled laboratory tests with various gases.

Bioinspired green fabricating design of ultra-breathable and moisture wicking fabric via a sustainable route

Functional textiles with breathability, thermal conductivity and moisture wicking performance are critical to achieving human comfort and reducing energy consumption. However, conventional finishing processes used for fabricating moisture wicking fabrics are usually highly polluting and exhibit poor durability as well as low recyclability, which may be detrimental to environmental sustainability. Inspired by the shorebird's beak with a conical-shaped liquid pathway for transporting liquid drops, a novel biomimetic porous fabric is proposed by using natural cotton fibers through industrial and eco-friendly knitting technology, featuring ultra-breathability, thermal conductivity and moisture wicking properties. Moreover, the effects of the pore size and arrangement on the thermal conductivity and air resistance are investigated. Obvious linearities can be obtained (R2 = 0.99). In addition, the synergistic effects of basic pore and biomimetic pore can create surface energy gradients, which result in the asymmetric pressure and water transport. As a result, when the biomimetic pore distances are 3 mm and 5 mm, respectively, high linearities of 0.99 between biomimetic pore diameter and the wicking height can be found. More importantly, the resultant biomimetic pore fabric exhibits good water absorption rate of 350%, an outstanding water vapor transmission (>10000 g/m2/24 h) and high recyclability. The green fabricating design of biomimetic porous fabric opens up a pathway to develop air, thermal, moisture regulating fabric through a sustainable route for more diverse applications, e.g., athletic apparel, industrial workwear and medical garments.

Synergistic enhancement for room and high temperature properties of Ti(C, N)-based cermets by Re and (Cr, La)2(C, N) assistance

Heat resistance played a crucial role in evaluating matrix material to meet the rapid development of molding industry. For the traditional Ti(C, N)-based cermets, softening and heat stocking induced degradation of mechanical properties limited its constant application under high-temperature. Herein, a novel engineering strategy for synergistically improving both room and high temperature properties was proposed by using Rhenium (Re) as additive in a (Cr, La)2(C, N) modified Ti(C, N)-based cermets. Results indicated that Re could effectively adjust the dissolution-precipitation process by dispersing into binder phase, which brought out more even microstructure and enhanced mechanical properties at both room and elevated temperatures. Benefitting from dissolution strengthening and purification effect at the interface by La, the increased thermal conductivity and thermal shocking resistance could also be obtained. With the co-enhancement of mechanical and physical properties, this new strategy could anticipate with significant potential for consideration as matrix materials in manufacturing.

Preparation and properties of fluorosilicone composites with thermal conductivity and chemical resistance through modification of filler and matrix

The improvement of heat dissipation and chemical resistance of encapsulating materials can greatly increase the service life of electronic devices. Fluorosilicone rubber exhibits superior chemical resistance compared to silicone rubber when used for encapsulation, enabling it to effectively handle highly complex application scenarios. In this study, a thermally conductive and chemically resistant composite material (i.e., F-Al2O3/F-AlN@F-ALSR) was prepared by introducing fluorine-modified Al2O3 and AlN into fluorine-added liquid silicone rubber matrix from both filler and matrix fluorination modification perspectives. The effects of the properties of fillers before and after modification, different mixing ratios (i.e., the ratio of F-Al2O3 to F-AlN) and different addition amounts (i.e., the amount of F-Al2O3/F-AlN added in F-ALSR) on the thermal conductivity and chemical medium resistance of the composite material were investigated, and the mechanisms of thermal conductivity and chemical medium resistance were explored. The results showed that when the ratio of F-Al2O3 to F-AlN was 3:7 and the total amount of filling was 300 phr, the material had a thermal conductivity of 1.047 W/mK and a thermal diffusivity of 0.652 mm2/s. The rate of change of mass and volume during 72 h of immersion in acid, alkali, toluene and engine oil was low. This further proves that the addition of F-Al2O3/F-AlN in F-ALSR can effectively create a heat conduction path and protect the composite material from environmental effects, resulting in materials with excellent thermal conductivity and chemical resistance. This study provides new ideas for improving the dispersion of fillers in the matrix and rationalizing the preparation of liquid silicone rubbers for thermally conductive, chemically resistant electronic potting.

Effects by geothermal gradient on thermal response tests for boreholes

A thermal response test (TRT) on a borehole provides information needed in the design of ground heat exchangers for ground source heat pump systems. Conventional analysis of TRT data sets uses the late-time period to estimate the ground thermal conductivity and the effective borehole resistance. During this quasi-steady-state period, the transient average fluid temperature has a logarithmic linear trend, which is consistent with conventional heat transfer models that assume a uniform undisturbed ground temperature. As the depth of the borehole increases the undisturbed ground temperature increases with depth following the geothermal gradient. This paper focuses on how the geothermal gradient affects a TRT. As the geothermal gradient increases, the required time to reach the conventional logarithmic linear trend may increase beyond any practical testing duration in coaxial boreholes. Then, conventional analysis methods based on a quasi-steady-state period incorrectly estimate the ground thermal conductivity. The magnitude of this effect is controlled through a dimensionless parameter |qratio|, which includes the geothermal gradient and other test parameters. In place of conventional models, a transient model that includes the geothermal gradient and fluid thermal storage can estimate the ground thermal conductivity and local borehole resistance within the typical TRT testing duration.

3D printing path method for multi-tow continuous carbon fiber

Carbon fiber composite materials have many excellent characteristics such as high temperature resistance, friction resistance, thermal conductivity and corrosion resistance, so carbon fiber composite materials have become the first choice for printing materials. In order to improve the printing efficiency of carbon fiber 3D printing technology, it has been expanded to four side-by-side nozzles based on traditional single nozzles, and four nozzles are bound to print side by side. The four-nozzle side-by-side printing path has the problem of coordinating the motion planning of each nozzle, controlling the squeezing difference of each nozzle, and adjusting the angle of the print head, so it is necessary to reasonably control the squeezing amount of each nozzle and the angle of the print head. After the slicing processing based on the existing model, the Gcode code of the model is obtained. The Gcode code of the model is processed through the multi-tow continuous carbon fiber 3D printing path planning algorithm. The movement trajectory of each nozzle of the printer is reasonably planned based on the outer wall coordinates and the extrusion amount of each nozzle is controlled. Finally, the snipping instruction is executed after a circle of trajectory to print the next layer of motion trajectory, which ultimately improves the 3D printing while ensuring the accuracy of multi-beam model 3D printing.

The Relevance of Surface Resistances on the Conductive Thermal Resistance of Lightweight Steel-Framed Walls: A Numerical Simulation Study

The accurate evaluation of the thermal performance of building envelope components (e.g., facade walls) is crucial for the reliable evaluation of their energy efficiency. There are several methods available to quantify their thermal resistance, such as analytical formulations (e.g., ISO 6946 simplified calculation method), numerical simulations (e.g., using finite element method), experimental measurements under lab-controlled conditions or in situ. Regarding measurements, when using the heat flow meter (HFM) method, very often, the measured value is based on surface conditions (e.g., temperature and heat flux), achieving in this way the so-called surface-to-surface or conductive thermal resistance (Rcond). When the building components are made of homogeneous layers, their Rcond values are constant, regardless of their internal and external surface boundary conditions. However, whenever this element is composed of inhomogeneous layers, such as in lightweight steel-framed (LSF) walls, their Rcond values are no longer constant, depending on their thermal surface resistance. In the literature, such systematic research into how these Rcond values vary is not available. In this study, the values of four LSF walls were computed, with different levels of thermal conductivity inhomogeneity, making use of four finite elements’ numerical simulation tools. Six external thermal surface resistances (Rse) were modelled, ranging from 0.00 up to 0.20 m2·K/W. The average temperature of the partition LSF walls is 15 °C, while for the facade LSF walls it is 10 °C. It was found that the accuracy values of all evaluated numerical software are very high and similar, the Rcond values being nearly constant for walls with homogeneous layers, as expected. However, the variation in the Rcond value depends on the level of inhomogeneity in the LSF wall layers, increasing up to 8%, i.e., +0.123 m2·K/W, for the evaluated Rse values.

Development of hBN/natural fibres reinforced polymer composites using grey relation grade analysis for thermal and electrical applications

The objective of this work is to enhance the thermal conductivity and electrical properties of polymer hybrid composites through a systematic novel grey relation grade analysis (GRGA) optimization approach. This involves reinforcing the hybrid composites with hexagonal boron nitride (hBN) and various kinds of natural fibers or fillers. The development of a unique technology to produce multiphase composites using 2% of natural fibers or fillers such as coir fiber, rice husk filler, wood filler (WF), banana fiber (BF) and sugarcane fiber along with hBN (1, 3, 5 wt.%) particulates as reinforcements in epoxy matrix. The Taguchi L15 matrix array is utilized to fabricate interlaced composite samples via hand layup molding. Ultrasonic waves are used to ensure the uniform distribution of hBN filler into the matrix. Analysis of variance and GRGA reveal the significant results. It shows that the multiphase hybrid composites exhibit good thermal conductivity when higher content of hBN (5 wt.%) particulate for all the micro particulate polymer (MPP) composites. Multi-response optimization shows that the micro BF (2 wt.%) interlaces with hBN (5 wt.%) composite exhibits the higher thermal conductivity and electrical resistance compared to all other natural fiber interlaced composites. The aforementioned MPP composite has thermal conductivity of 1.03 W (m·K)−1 and electrical resistance of 279.88 Giga Ohms. Besides, the WF interlaced hBN (5 wt.%) composite shows the minimum dielectric constant compared to all other natural fiber composites. This desirable result is caused by the proper dispersion of hBN with the matrix which encourages interlocking with the fiber and the matrix. Maximum electrical resistance is observed for composite containing 5 wt.% of h-BN and 2 wt.% of BF. The developed MPP composite could be used in heat shields, electrical insulation components, and interior automotive components like dashboards, luggage compartments and interior walls.

Numerical investigation of the saturation effect on wick dry-out in a capillary driven evaporative cooling system

The influence of gravity in vertically oriented capillary-driven evaporative cooling systems utilizing porous structures in devices such as heat pipes, vapour chambers and direct wick-based cooling is nontrivial. This can impede the rise of liquid through the structure, diminishing wick saturation. Here we developed a model to quantify the variation of saturation in a vertically oriented porous structure operating at low heat fluxes, with a focus in their use in evaporative cooling of batteries. The model was validated within 15% of the experimental data, and a parametric study was conducted to assess the impact of wick parameters on saturation. Dry-out height and dry-out heat flux were also determined across a range of heat fluxes and wick thicknesses, considering various porosities. Findings indicate that saturation increases with increasing porosity and wick thickness, while decreasing with increasing particle diameter. Furthermore, as porosity and wick thickness increase, the thermal conductive resistance of the wick experiences a substantial increase. Wick porosity has the most significant influence on dry-out height, saturation, and thermal conductive resistance. These insights are valuable for designing capillary-driven evaporative cooling systems operating under gravity.

Hydrogen evolution and thermal treatments for removal of plating induced impurities from Ni to extend life of solder joints

As operating temperatures and times continue to increase for solder joints with Ni pads, large voids inevitably form at the intermetallic compound (IMC) – solder interface when the IMC thickness nears 5 μm. This leads to a significant reduction of strength, thermal conductivity, and fatigue resistance, and in small joints, also to electromigration life degradation. We have identified the voiding root cause as the breakdown and subsequent outgassing of deposition-related Ni-oxo-hydroxide impurities, impractical to avoid during Ni commercial electroplating. This work takes as the starting point a successful post-deposition voiding-mitigation treatment with 24-hour annealing at 450 °C. It then explores the possibility of rendering this routine more practical by lowering the annealing temperature down to 250 °C. While that approach shows relatively limited success, an alternative strategy, involving treatment with hydrogen evolution reaction for one hour at room temperature, alone or in combination with thermal, leads to a substantial reduction in the voiding propensity.

Mechanical and Thermal Properties of an Energy-Efficient Cement Composite Incorporating Silica Aerogel

The thermal performance of the building envelope is significant in energy-efficient construction. Because concrete is widely used in civil engineering, options to reduce its R-value should be considered. This study explores the thermal and structural properties of aerogel-enhanced concrete. Silica aerogel powder was mixed with fine-grained concrete at 15 vol.%. Two series of samples were prepared to identify the preferred technology. The first series of samples were mixed without isopropyl alcohol; for the second series, the alcohol was mixed with silica aerogel before mixing into the dry mix. The thermal conductivity, compressive strength, and bending resistance of the specimens were measured. The presence of silica aerogel admix resulted in a decrease in the compressive strength of the specimens by 30% compared with that of the reference samples and a reduction in the bending strength of the samples by 9% compared with that of the reference samples. For the first and second series of samples, the K-values of the aerogel-enhanced specimens varied in the range from 0.83 W/(m·K) to 1.13 W/(m·K), respectively. To further decrease the thermal conductivity, gypsum putty was then added to the specimens, resulting in the K-values further decreasing to 0.64 W/(m·K) and 0.84 W/(m·K), respectively. The calculation of heat losses through 1 m2 of the aerogel-enhanced concrete wall was performed. It has been shown that energy expenses for heating can be lowered by 30%. The calculation of the greenhouse gas emissions from the combustion of fuel required for heating was also considered. The emissions decreased by 30.2% compared with the reference sample. Microscopic examination of the face and section surfaces of the sample revealed a significant number of pores compared with conventional fine-grain concrete.

Innovative Cellular Insulation Barrier on the Basis of Voronoi Tessellation-Influence of Internal Structure Optimization on Thermal Performance.

The optimization of structure and thermal properties in 3D-printed insulation materials remains an underexplored area in the literature. This study aims to address this gap by investigating the impact of 3D printing on the thermal properties of manufactured cellular composites. The materials studied were closed-cell foams with a complex cell structure based on the Voronoi cell model, manufactured using incremental technology (3D printing). The influence of the cellular structure of the composite, the type of material used, and the number of layers in the composite structure on its thermal properties, i.e., thermal conductivity coefficient, thermal resistance, and coefficient of heat transfer, was analyzed. Samples of different types of thermosetting resins, characterized by different values of emissivity coefficient, were analyzed. It was shown that both the type of material, the number of layers of the composite, and the number of pores in its structure significantly affect its thermal insulating properties. Thermal conductivity and permeability depended on the number of layers and decreased up to 30% as the number of layers increased from one to four, while thermal resistance increased to 35%. The results indicate that material structure is key in regulating thermal conduction. Controlling the number of cells in a given volume of composite (and thus the size of the air cells) and the number of layers in the composite can be an effective tool in designing materials with high insulation performance. Among the prototype composites produced, the best thermal performance was that of the metalized four-layer cellular composites (λ = 0.035 ± 0.002 W/m·K, Rc = 1.15 ± 0.02 K·m2/W, U = 0.76 ± 0.01 W/m2·K).

Deep Potential fitting and mechanical properties study of MgAlSi alloy

MgAlSi alloy materials have the main properties of light weight and high strength, good electrical and thermal conductivity and corrosion resistance, and have various applications in the industrial field, making an important contribution to the realization of lightweight and high performance needs. In order to be able to predict the material properties of MgAlSi alloys with a high degree of accuracy, this paper develops for the first time an interatomic potential function for MgAlSi alloys based on a neural network machine learning approach. The effectiveness of the developed machine learning potentials is verified by analyzing the problems encountered during the training process and the errors of the finally obtained potential functions, and comparing some of the radial distribution functions, coordination numbers, and predictions of properties such as the equation of state, lattice constants, shear modulus and bulk modulus with those of AIMD. It is found that the performance error of the deep potential model is basically kept in the same order of magnitude as that of DFT calculations, the computational speed can be up to nearly a thousand times that of DFT, and the computational cost is linearly related to the atomic number, which is well suited for large-scale molecular dynamics simulations, and it will provide a promising solution for accurate large-scale molecular dynamics simulations.

Effect of segment structure of monotrimethoxysilylethyl-terminated asymmetric polysiloxanes on the thermal management performance of AlN-filled silicone pastes

Three kinds of α-triethylsiloxyl-ω-trimethoxysilyethyl-terminated oligomers (TES-PDMS-TMOS, TES-PTFPMS-TMOS, and TES-PDES-TMOS) were synthesized through an anion catalyzed non-equilibrium ring-opening polymerization reaction of cyclotrisiloxanes and subsequent hydrosilylation reaction with vinyltrimethoxysilane. As the in situ surface modification agent for mixed-size AlN inorganic fillers (1, 20 and 50 μm blended in a mass ratio of 3:5:9), these oligomers have been mixed with Vi-PDMS in a mass ratio of 1:2. Relative to that of silicone pastes using Vi-PDMS as the polymer matrix, the thermal conductivity of silicone pastes made from AlN particles treated with these oligomers is enhanced, while their thermal resistances decreased. With the change of the repeating unit structure in the oligomers, the silicone pastes prepared from these oligomer-treated AlN fillers differ significantly in filler content, thermal conductivity, and thermal resistance. When TES-PTFPMS-TMOS is used and filled with 800 parts (70.3 vol%) of hybrid AlN powders, a silicone paste with a thermal conductivity of 4.56 W/(m. K) could be achieved, which was 37.8% higher than that silicone paste using pure Vi-PDMS as the matrix. When TES-PDES-TMOS is used and filled with 900 parts (72.7 vol%) of hybrid AlN powders, the thermal conductivity of the silicone paste reaches 4.13 W/(m. K). Despite its thermal conductivity being only 3.5% higher relative to the silicone paste using only Vi-PDMS as the polymer matrix, its thermal resistance decreased by 20.3%. When TES-PDMS-TMOS is used and filled with 1200 parts (78.0 vol%) of hybrid AlN powders, the thermal conductivity of the silicone paste could reach up to 4.59 W/(m. K), together with a thermal resistance 29.6% lower than that of silicone paste where 1000 parts (74.7 vol%) of hybrid AlN particles filled in the Vi-PDMS. The heat dissipation of the 30 W high-brightness LED chip also illustrated the excellent thermal conductivities of these silicone pastes. The effect of another terminal group on the monotrimethoxysilylethyl-terminated asymmetric polysiloxanes on the thermal resistance of thermal interface materials was also discussed in detail.

Correlations among physical properties of pervious concrete with different aggregate sizes and mix proportions

Permeable pavement material can benefit urban environment. Here in this work, different aggregate sizes and mix proportions were used to manufacture pervious pavement concrete and investigate correlations among its properties. The porosity, permeability, compressive strength, inner structure, thermal conductivity, and abrasion resistance of the specimens were obtained. Results showed lower aggregate-to-cement ratios and higher water-to-cement ratios led to porosity reduction, which decreased the permeability coefficient but increased the compressive strength, thermal conductivity, and abrasion resistance of the pervious concrete. Compared to the mixes, the aggregate sizes affected the physical properties of pervious concrete less. However, the sizes of pores and cement in the pervious concrete were more affected by aggregate sizes than by mixes. Moreover, the porosity, permeability coefficient, and compressive strength of the pervious concrete can be correlated by the power law, whereas the correlation between the porosity and abrasion resistance index can be fitted by a linear law.

Irradiation resistance of thermo-optical properties of zirconium diboride by 3 MeV electrons

Due to good thermal conductivity and thermal shock resistance, ultra-high temperature ceramics such as zirconium diboride (ZrB2) have been investigated as promising materials to be used in reusable thermal protection systems TPSs are vital to the heat balance of a spacecraft during atmospheric reentry and subsequent operation in space. Hence, the thermal and optical properties are especially critical for such applications. Meanwhile, radiation exposure in space can pose risks of degrading such material properties, especially over a prolonged mission duration. The interaction of electron radiation-which can be found in the outer Van Allen belt, with ZrB2 has not been studied previously and was chosen as the main scope of this study. An electron source of 3 MeV with different radiation exposure time was used. The response of thermo-optical properties of ZrB2 to increasing electron radiation fluences was investigated. ZrB2 samples were made through spark plasma sintering into sintered pellets and then exposed to 3 MeV electron irradiation. These ZrB2 samples were characterized by their microstructure, thermal conductivity, coefficient of thermal expansion (CTE), emittance, absorptivity, and surface roughness before and after irradiation. It was found that ZrB2’s thermo-optical properties showed high radiation resistance at these fluences, and no apparent microstructural change was observed after irradiation. However, the irradiated samples had, on average, a 29% lower surface roughness than the unirradiated samples, possibly originating from electron sputtering.

BN green gel thermal interface material with high thermal conductivity and low thermal contact resistance for efficiently thermal management

As an important component of electronic devices, thermal interface materials (TIMs) provide a fast heat dissipation channel, which will significantly improve the reliability and long-term stability of electronic devices. Gel TIMs with good flexibility is a development direction for thermal management in the future. However, the green and environmental issues in the preparation of gel TIMs with good stability are also important problems that must be considered. Here, combining the advantages of green deep eutectics solvents and high thermal conductivity boron nitride, a boron nitride polymerizable deep eutectics solvents gel composite TIMs with high thermal conductivity, good stability and low thermal contact resistance (TCR) has been developed. The thermal conductivity of composite TIMs achieved 1.18 W/m·K at a boron nitride loading of 20 wt%. Under pressure gradient testing (10 Psi-50 Psi), the TCR of composite TIMs decreased to 0.76 K·cm2/W. In the temperature gradient test (30 °C-70 °C), the TCR of the composite TIMs dropped to 0.143 K·cm2/W. Furthermore, in the TCR cycling test, the composites showed better cycling stability. In addition, composite TIMs also show better thermal performance in practical applications. This work provides a green way for the fabrication of gel TIMs with high thermal conductivity, good stability and low TCR.

Modulation and optimisation of the properties of n-decanoic acid-tetradecanol phase change materials by nanocomposite carbon materials prepared by atomic layer deposition methods

Phase change materials limit practical applications due to their relatively weak thermal conductivity and leakage resistance. The present work focuses on the development of a novel composite PCM (CA-TD/ZnO/EG), which was prepared by adsorbing a binary mixture of n-decanoic acid-tetradecanol (CA-TD) based on the combination of expanded graphite (EG) and zinc oxide (ZnO) nanoparticles. A new support material, ZnO/EG, was assembled by depositing specially shaped ZnO onto the surface of an expanded graphite substrate using an atomic deposition method. In addition to maintaining the porous structure of EG and preventing the leakage of CA-TD, the ZnO/EG reduces the interfacial thermal resistance between the substrate and the PCM molecules, which leads to the maximisation of the thermal conductivity. The prepared CA-TD/ZnO/EG-10 composite has a phase transition temperature of 19.5 °C, a heat of 157.3 J/g, and a thermal conductivity of (6.131 W·m−1·K−1) improved by 351.7% compared to the CA-TD material. Its faster heat transfer rate is directly reflected in the infrared image, with a small enthalpy change of 1.2% during 200 cycles of heating-cooling, as well as some photothermal conversion capability. The results of this paper can provide prospects for the functional design, modification, and enhancement of composite PCM.