The rapid development of the information era has led to in-creased power consumption,which generates more heat.This requires more efficient thermal management systems,with the most direct ap-proach being the developme...The rapid development of the information era has led to in-creased power consumption,which generates more heat.This requires more efficient thermal management systems,with the most direct ap-proach being the development of su-perior thermal interface materials(TIMs).Mesocarbon microbeads(MCMBs)have several desirable properties for this purpose,includ-ing high thermal conductivity and excellent thermal stability.Although their thermal conductivity(K)may not be exceptional among all carbon materials,their ease of production and low cost make them ideal filler materials for developing a new generation of carbon-based TIMs.We report the fabrication of high-performance TIMs by incorporating MCMBs in a polyimide(PI)framework,producing highly graphitized PI/MCMB(PM)foams and anisotropic polydimethylsiloxane/PM(PDMS/PM)composites with a high thermal conductivity using directional freezing and high-temperature thermal annealing.The resulting materials had a high through-plane(TP)K of 15.926 W·m^(−1)·K^(−1),4.83 times that of conventional thermally conductive silicone pads and 88.5 times higher than that of pure PDMS.The composites had excellent mechanical properties and thermal stability,meeting the de-mands of modern electronic products for integration,multi-functionality,and miniaturization.展开更多
Phase change thermal interface materials(PC-TIMs)have emerged as a promising solution to address the increasing thermal management challenges in electronic devices.This is attributed to their dual mechanisms of latent...Phase change thermal interface materials(PC-TIMs)have emerged as a promising solution to address the increasing thermal management challenges in electronic devices.This is attributed to their dual mechanisms of latent heat absorption and phase change-induced interfacial wettability.This review explores the fundamental principles,material innovations,and diverse applications of PC-TIMs.The heat transfer enhancement mechanisms are first underlined with key factors such as thermal carrier mismatch at the microscale and contact geometry at the macroscale,emphasizing the importance of material selection and design for optimizing thermal performance.Section 2 focuses on corresponding experimental approaches provided,including intrinsic thermal conductivity improvements and interfacial heat transfer optimization.Section 3 discusses common methods such as physical adsorption via porous materials,chain-crosslinked network designs,and core-shell structures,and their effects on leakage prevention,heat transfer enhancement,and application flexibility.Furthermore,the extended applications of PC-TIMs in thermal energy storage are explored in Section 4,suggesting their potential in diverse technological fields.The current challenges in interfacial heat transfer research and the prospect of PC-TIMs are also discussed.The data-driven machine learning technologies will play an increasingly important role in addressing material development and performance prediction.展开更多
Thermal resistance of low-melting-temperature alloy （LMTA） thermal interface materials （TIMs） was measured by laser flash method before and after different stages of heating. The results showed that the thermal pe...Thermal resistance of low-melting-temperature alloy （LMTA） thermal interface materials （TIMs） was measured by laser flash method before and after different stages of heating. The results showed that the thermal performance of the LMTA TIMs was degraded during the heating process. It is suggested that the degradation may mainly be attributed to the interfacial reaction between the Cu and the molten LMTAs. Due to the fast growth rate of intermetallic compound （IMC） at the solid-liquid interface, a thick brittle IMC is layer formed at the interface, which makes cracks easy to initiate and expand. Otherwise, the losses of indium and tin contents in the LMTA during the interfacial reaction will make the melting point of the TIM layer increase, and so, the TIM layer will not melt at the operating temperature.展开更多
Thermal interface materials(TIMs)play a vital role in the thermal management of electronic devices and can significantly reduce thermal contact resistance(TCR).The TCR between the solid–liquid contact surface is much...Thermal interface materials(TIMs)play a vital role in the thermal management of electronic devices and can significantly reduce thermal contact resistance(TCR).The TCR between the solid–liquid contact surface is much smaller than that of the solid–solid contact surface,but conventional solid–liquid phase change materials are likely to cause serious leakage.Therefore,this work has prepared a new formstable phase change thermal interface material.Through the melt blending of paraffin wax(PW)and low-density polyethylene(LDPE),the stability is improved and it has an excellent coating effect on PW.The addition of aluminum(Al)powder improves the low thermal conductivity of PW/LDPE,and the addition of 15wt%Al powder improves the thermal conductivity of the internal structure of the matrix by 67%.In addition,the influence of the addition of Al powder on the internal structure,thermal properties,and phase change behavior of the PW/LDPE matrix was systematically studied.The results confirmed that the addition of Al powder improved the thermal conductivity of the material without a significant impact on other properties,and the thermal conductivity increased with the increase of Al addition.Therefore,morphologically stable PW/LDPE/Al is an important development direction for TIMs.展开更多
Interface engineering is proved to be the most important strategy to push the device performance of the perovskite solar cell(PSC) to its limit, and numerous works have been conducted to screen efficient materials. He...Interface engineering is proved to be the most important strategy to push the device performance of the perovskite solar cell(PSC) to its limit, and numerous works have been conducted to screen efficient materials. Here, on the basis of the previous studies, we employ machine learning to map the relationship between the interface material and the device performance, leading to intelligently screening interface materials towards minimizing voltage losses in p-i-n type PSCs. To enhance the explainability of the machine learning models, molecular descriptors are used to represent the materials. Furthermore,experimental analysis with different characterization methods and device simulation based on the drift-diffusion physical model are conducted to get physical insights and validate the machine learning models. Accordingly, 3-thiophene ethylamine hydrochloride(Th EACl) is screened as an example, which enables remarkable improvements in VOCand PCE of the PSCs. Our work reveals the critical role of datadriven analysis in the high throughput screening of interface materials, which will significantly accelerate the exploration of new materials for high-efficiency PSCs.展开更多
Thermal contact resistance plays a very important role in heat transfer efficiency and thermomechanical coupling response between two materials,and a common method to reduce the thermal contact resistance is to fill a...Thermal contact resistance plays a very important role in heat transfer efficiency and thermomechanical coupling response between two materials,and a common method to reduce the thermal contact resistance is to fill a soft interface material between these two materials.A testing system of high temperature thermal contact resistance based on INSTRON 8874 is established in the present paper,which can achieve 600 C at the interface.Based on this system,the thermal contact resistance between superalloy GH600 material and three-dimensional braid C/C composite material is experimentally investigated,under different interface pressures,interface roughnesses and temperatures,respectively.At the same time,the mechanism of reducing the thermal contact resistance with carbon fiber sheet as interface material is experimentally investigated.Results show that the present testing system is feasible in the experimental research of high temperature thermal contact resistance.展开更多
Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal conductivity.The role of filler surface modificat...Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal conductivity.The role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully understood.This study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based TIMs.Our findings reveal that the variations of SCAs modify both interface binding energy and transition layer thickness.The interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line thickness.On the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and filler.Consequently,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.展开更多
The growing concern about thermal conductivityand electromagnetic shielding inelectronic equipment has promoted the development of interfacial film materials.In this work,polyvinylidene fluoride(PVDF)/graphene composi...The growing concern about thermal conductivityand electromagnetic shielding inelectronic equipment has promoted the development of interfacial film materials.In this work,polyvinylidene fluoride(PVDF)/graphene composite films with different graphene contents were fabricated by high-energy ball milling,cold isostatic pressing,scraping and coating,successively.High-energy ball milling is beneficial to the dispersion of graphene powder,while cold isostatic pressing can greatly enhance thermal conductivity and mechanical strength by reducing the voids in the film and increasing the contact area of graphene sheets.The thermal conductivity,tensile strength and electromagnetic shielding properties of the films were carefully investigated and compared.It was demonstrated that the thermal conductivity increased from 0.19 W·m^(-1).K^(-1) for pure PVDF to 103.9 W·m^(-1).K^(-1)for the composite film with PVDF:graphene=1:3.Meanwhile the electromagnetic shielding efficiency can reach 36.55 dB.The prepared PVDF/graphene composite films exhibit outstanding overall performance and have the potential for practical applications.展开更多
Developing advanced thermal interface materials(TIMs)to bridge heat-generating chip and heat sink for constructing an efficient heat transfer interface is the key technology to solve the thermal management issue of hi...Developing advanced thermal interface materials(TIMs)to bridge heat-generating chip and heat sink for constructing an efficient heat transfer interface is the key technology to solve the thermal management issue of high-power semiconductor devices.Based on the ultra-high basal-plane thermal conductivity,graphene is an ideal candidate for preparing high-performance TIMs,preferably to form a vertically aligned structure so that the basal-plane of graphene is consistent with the heat transfer direction of TIM.However,the actual interfacial heat transfer efficiency of currently reported vertically aligned graphene TIMs is far from satisfactory.In addition to the fact that the thermal conductivity of the vertically aligned TIMs can be further improved,another critical factor is the limited actual contact area leading to relatively high contact thermal resistance(20-30 K mm^(2) W^(−1))of the“solid-solid”mating interface formed by the vertical graphene and the rough chip/heat sink.To solve this common problem faced by vertically aligned graphene,in this work,we combined mechanical orientation and surface modification strategy to construct a three-tiered TIM composed of mainly vertically aligned graphene in the middle and micrometer-thick liquid metal as a cap layer on upper and lower surfaces.Based on rational graphene orientation regulation in the middle tier,the resultant graphene-based TIM exhibited an ultra-high thermal conductivity of 176 W m^(−1) K^(−1).Additionally,we demonstrated that the liquid metal cap layer in contact with the chip/heat sink forms a“liquid-solid”mating interface,significantly increasing the effective heat transfer area and giving a low contact thermal con-ductivity of 4-6 K mm^(2) W^(−1) under packaging conditions.This finding provides valuable guidance for the design of high-performance TIMs based on two-dimensional materials and improves the possibility of their practical application in electronic thermal management.展开更多
Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected...Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.展开更多
Down to the road of miniaturization and high power density,the heat dissipation is becoming one of the critical factors restricting further development of advanced microelectronic devices.Traditional polymer-based the...Down to the road of miniaturization and high power density,the heat dissipation is becoming one of the critical factors restricting further development of advanced microelectronic devices.Traditional polymer-based thermal interface materials(TIMs) are not competitive for the high efficiency thermal management,mainly due to their low intrinsic thermal conductivity and high interface thermal resistance.Solder-based TIM is one of the best candidates for the next generation of thermal interface materials.This paper conducts a perspective review of the state of the art of solder TIM,including low melting alloy solder TIM,composite solder TIM and nanostructured solder TIM.The microstructure,process parameters,thermal performance and reliability of different TIMs are summarized and analyzed.The future trends of advanced TIMs are discussed.展开更多
Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of ...Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of nonfullerene materials,achieving individual cell efficiencies that surpass 19%.Hence,the stability of nonfullerene solar cell production must be scrutinized.The stability of the cathode interface layer significantly impacts the overall stability of OSC devices.PFN-Br,a commonly employed cathode interface material,is susceptible to degradation due to its sensitivity to environmental humidity,consequently compromising the device stability.In this study,we introduce fluorescent dye molecules,rhodamine 101,as cathode interface layers in OSCs to establish device stability and assess their universality.A comparative investigation of rhodamine 101 and PFN-Br devices demonstrates the former’s distinct advantages in terms of thermal stability,photostability,and storage stability even without encapsulation,particularly in an inert environment.By employing the Kelvin probe,we compare the work function of different cathode interface films and reveal that the work function of the rhodamine 101 interface material remains relatively unaffected by environmental factors.As a consequence,the device performance stability is significantly enhanced.The application of such fluorescent dye molecules extends the scope of cathode interface layers,amplifies device stability,and propels industrialization.展开更多
The continuous miniaturization and high-power development of electronic devices have given rise to severe interface thermal issues,which urgently demand highly thermally conductive thermal interface materials(TIMs)to ...The continuous miniaturization and high-power development of electronic devices have given rise to severe interface thermal issues,which urgently demand highly thermally conductive thermal interface materials(TIMs)to eliminate excessive heat accumulation and ensure the normal operation of devices[1].展开更多
With the rapid development of artificial intelligence(AI)and big data technologies,electronic devices are evolving toward higher integration and power density,posing severe challenges for thermal dissipation.High-perf...With the rapid development of artificial intelligence(AI)and big data technologies,electronic devices are evolving toward higher integration and power density,posing severe challenges for thermal dissipation.High-performance thermal interface materials(TIMs)used for minimizing the interfacial thermal resistance between the heater and heat sink are key to achieving efficient thermal management of electronic devices.To date,significant progress has been made in achieving high thermal conductivity by constructing oriented structures in TIMs.In this review,we systematically summarize and discuss the preparation methods for the design of TIMs with oriented structure.Furthermore,we particularly review the recent advancements in improving thermal contact resistance in oriented TIMs and emphasize that when the intrinsic thermal conductivity of the TIM is sufficiently high,thermal contact resistance becomes the primary bottleneck in heat dissipation.Finally,we outline the fundamentals of TIMs,the challenges,and potential directions associated with orientation structural design and practical applications,aiming to provide insights into the development of highperformance TIMs.展开更多
Boron nitride nanoflakes(BNNF)are rendered as ideal thermal conductivity fillers for thermal interface materials(TIMs)due to their ultrahigh thermal conductivity(TC)and superior electronic insulation.However,it is dif...Boron nitride nanoflakes(BNNF)are rendered as ideal thermal conductivity fillers for thermal interface materials(TIMs)due to their ultrahigh thermal conductivity(TC)and superior electronic insulation.However,it is difficult to guarantee the high yield of well dispersed BNNF in the polymer matrix for industrial production.Herein,we propose a novel“in-situ exfoliation”strategy to fabricate the thin BNNF via chemical bonding engineering.By enhancing theπ-πstacking between the inclusion and matrix,the average thickness of the BN is efficiently reduced during the three-roll mixing process.The as-prepared BNNF composite presents ultrahigh in-plane TC(10.58 W·m^(−1)·K^(−1))with 49.5%(in mass)BN loading at 100 parts per hundreds of rubber(phr)with simultaneously enhanced flexibility.Notably,the tensile strength,the initial thermal decomposition temperatures(T5%)and elongation at break of the composite can reach 4.94 MPa,470.6℃and 98%,respectively.Our LED chip cooling tests validate the outstanding heat dissipation ability of the composites for TIM applications.Furthermore,this strategy also proves effective in exfoliating the graphite flakes,demonstrating excellent generalization capability.This work opens up a new avenue for developing the high-performance TIMs,showing huge potential in large-scale production.展开更多
As an important component to connect the electron transport layer(ETL)and the cathode electrode,the cathode interface layer(CIL)is key to enhancing electron transport and suppressing metal electrode corrosion in inver...As an important component to connect the electron transport layer(ETL)and the cathode electrode,the cathode interface layer(CIL)is key to enhancing electron transport and suppressing metal electrode corrosion in inverted perovskite solar cells(PSCs).In this work,three D-A-D type cathode interface materials(DPP-PhN,DPP-F3N,and ffBT-F3N)are designed and synthesized employing dimethylamino-benzene or bis(dimethylamino)propyl-fluorene as electron donating(D)unit,and pyrrolo[3,4-c]-pyrrole-1,4-dione(DPP)or benzothiadiazole(BT)as electron accepting(A)unit for efficient inverted PSCs.The impact of variations in the A and D units on the energy levels,conductivity,interfacial dipoles,and carrier interfacial dynamics of CILs were systematically studied.On the one hand,DPP-F3N possesses the highest conductivity and the strongest interfacial dipole.On the other hand,the DPP-F3N is most favorable for forming ohmic contacts between the ETL and the cathode electrode to improve electron transport and prevent carrier recombination.As a result,the inverted PSCs using DPP-F3N as the CIL obtained the highest power conversion efficiency(PCE)of 25.19%.However,in terms of stability,the ffBT-F3N-based inverted PSCs show the best stability due to the strong interaction between the ffBT-F3N and the Ag electrode,which could effectively delay the corrosion of the Ag electrode.展开更多
The past years has observed a significantly boost of the thermoelectric materials in the scale of thermoelectric figure-of-merit,i.e.ZT,because of its promising application to harvest the widely distributed waste heat...The past years has observed a significantly boost of the thermoelectric materials in the scale of thermoelectric figure-of-merit,i.e.ZT,because of its promising application to harvest the widely distributed waste heat.However,the simplified thermoelectric materials'performance scale also shifted the focus of thermoelectric energy conversion technique from devices-related efforts to materials-level works.As a result,the thermoelectric devices-related works didn't get enough attention.The device-level challenges behind were kept unknown until recent years.However,besides the thermoelectric materials properties,the practical energy conversion efficiency and service life of thermoelectric device is highly determined by assembling process and the contact interface.In this perspective,we are trying to shine some light on the device-level challenge,and give a special focus on the thermoelectric interface materials(TEiM)between the thermoelectric elements and electrode,which is also known as the metallization layer or solder barrier layer.We will go through the technique concerns that determine the scope of the TEiM,including bonding strength,interfacial resistance and stability.Some general working principles are summarized before the discussion of some typical examples of searching proper TEiM for a given thermoelectric conversion material.展开更多
As electronic devices continue to evolve toward miniaturization and integration,traditional thermal interface materials(TIMs)are no longer able to meet the ever-tougher thermal management challenges.Owing to their hig...As electronic devices continue to evolve toward miniaturization and integration,traditional thermal interface materials(TIMs)are no longer able to meet the ever-tougher thermal management challenges.Owing to their high thermal conductivity and excellent conformability within a highly confined space,liquid metals have great potential for advanced thermal management in various cutting-edge devices and have become a key candidate for next-generation high-performance TIMs.In addition to already known materials,such as liquid metal alloy TIMs,particle-filled liquid metal TIMs,and liquid metal-filled TIMs,more TIMs are still being developed.This review presents a systematic classification of the liquid metal TIMs developed thus far,interprets the fundamental mechanisms underlying material innovation and in-situ heat transfer enhancement,and comparatively evaluates their respective advantages and shortcomings.Subsequently,a series of representative theoretical models for characterizing the thermal conductivities of composites are summarized,and the limits of the thermal conductivity of liquid metal TIMs are predicted to guide practical R&D efforts.To address the urgent need for higher-performance TIMs to overcome future thermal management challenges of electronic devices,a roadmap is outlined for the development of high-performance liquid metal TIMs,and a strategy for running these technologies is demonstrated.展开更多
Vertically aligned carbon nanotubes arrays(VACNTs)are a promising candidate for the thermal interface material(TIM)of next-generation electronic devices due to their attractive thermal and mechanical properties.Howeve...Vertically aligned carbon nanotubes arrays(VACNTs)are a promising candidate for the thermal interface material(TIM)of next-generation electronic devices due to their attractive thermal and mechanical properties.However,the environment required for synthesizing VACNTs is harsh and severely incompatible with standard device packaging processes.VACNTs’extremely low in-plane thermal conductivity also limits its performance for cooling hot spots.Here,using a transfer-and-encapsulate strategy,a two-step soldering method is developed to cap both ends of the VACNTs with copper microfoils,forming a standalone Cu-VACNTs-Cu sandwich TIM and avoiding the need to directly grow VACNTs on chip die.This new TIM is fully compatible with standard packaging,with excellent flexibility and high thermal conductivities in both in-plane and through-plane directions.The mechanical compliance behavior and mechanism,which are critical for TIM applications,are investigated in depth using in situ nanoindentation.The thermal performance is further verified in an actual light emitting diode(LED)cooling experiment,demonstrating low thermal resistance,good reliability,and achieving a 17℃ temperature reduction compared with state-of-the-art commercial TIMs.This study provides a viable solution to VACNTs’longstanding problem in device integration and free-end contact resistance,bringing it much closer to application and solving the critical thermal bottleneck in next-generation electronics.展开更多
The emerging applications of composite gels as thermal interface ma-terials(TIMs)for chip heat dissipation in intelligent vehicle and wear-able devices require high thermal conductivity and remarkable damp-ing propert...The emerging applications of composite gels as thermal interface ma-terials(TIMs)for chip heat dissipation in intelligent vehicle and wear-able devices require high thermal conductivity and remarkable damp-ing properties.However,thermal conductivity and damping proper-ties are usually correlated and coupled each other.Here,inspired by Maxwell theory and adhesion mechanism of gecko’s setae,we present a strategy to fabricate polydimethylsiloxane-based composite gels in-tegrating high thermal conductivity and remarkable damping prop-erties over a broad frequency and temperature range.The multiple relaxation modes of dangling chains and the dynamic interaction be-tween the dangling chains and aluminum fillers can efficiently dis-sipate the vibration energy,endowing the composite gels with ultra-high damping property(tanδ>0.3)over a broad frequency(0.01-100 Hz)and temperature range(-50-150°C),which exceeds typi-cal state-of-the-art damping materials.The dangling chains also com-fort to the interfaces between polymer matrix and aluminum via van der Waals interaction,resulting in high thermal conductivity(4.72±0.04 W m-1 K-1).Using the polydimethylsiloxane-based composite gel as TIMs,we demonstrate effective heat dissipation in chip oper-ating under vigorous vibrations.We believe that our strategy could be applied to a wide range of composite gels and lead to the devel-opment of high-performance composite gels as TIMs for chip heat dissipation.展开更多
文摘The rapid development of the information era has led to in-creased power consumption,which generates more heat.This requires more efficient thermal management systems,with the most direct ap-proach being the development of su-perior thermal interface materials(TIMs).Mesocarbon microbeads(MCMBs)have several desirable properties for this purpose,includ-ing high thermal conductivity and excellent thermal stability.Although their thermal conductivity(K)may not be exceptional among all carbon materials,their ease of production and low cost make them ideal filler materials for developing a new generation of carbon-based TIMs.We report the fabrication of high-performance TIMs by incorporating MCMBs in a polyimide(PI)framework,producing highly graphitized PI/MCMB(PM)foams and anisotropic polydimethylsiloxane/PM(PDMS/PM)composites with a high thermal conductivity using directional freezing and high-temperature thermal annealing.The resulting materials had a high through-plane(TP)K of 15.926 W·m^(−1)·K^(−1),4.83 times that of conventional thermally conductive silicone pads and 88.5 times higher than that of pure PDMS.The composites had excellent mechanical properties and thermal stability,meeting the de-mands of modern electronic products for integration,multi-functionality,and miniaturization.
基金funding from the National Natural Science Foundation of China(Grant Nos.52306214,52425601,and 52276074)the Shanghai Chenguang Plan Program(Grant No.22CGA78)the National Key Research and the Development Program of China(Grant No.2023YFB4404104)。
文摘Phase change thermal interface materials(PC-TIMs)have emerged as a promising solution to address the increasing thermal management challenges in electronic devices.This is attributed to their dual mechanisms of latent heat absorption and phase change-induced interfacial wettability.This review explores the fundamental principles,material innovations,and diverse applications of PC-TIMs.The heat transfer enhancement mechanisms are first underlined with key factors such as thermal carrier mismatch at the microscale and contact geometry at the macroscale,emphasizing the importance of material selection and design for optimizing thermal performance.Section 2 focuses on corresponding experimental approaches provided,including intrinsic thermal conductivity improvements and interfacial heat transfer optimization.Section 3 discusses common methods such as physical adsorption via porous materials,chain-crosslinked network designs,and core-shell structures,and their effects on leakage prevention,heat transfer enhancement,and application flexibility.Furthermore,the extended applications of PC-TIMs in thermal energy storage are explored in Section 4,suggesting their potential in diverse technological fields.The current challenges in interfacial heat transfer research and the prospect of PC-TIMs are also discussed.The data-driven machine learning technologies will play an increasingly important role in addressing material development and performance prediction.
基金supported by the National Basic Research Program of China (No.2010CB631006)the National Natural Science Foundation of China (No.51171191)
文摘Thermal resistance of low-melting-temperature alloy （LMTA） thermal interface materials （TIMs） was measured by laser flash method before and after different stages of heating. The results showed that the thermal performance of the LMTA TIMs was degraded during the heating process. It is suggested that the degradation may mainly be attributed to the interfacial reaction between the Cu and the molten LMTAs. Due to the fast growth rate of intermetallic compound （IMC） at the solid-liquid interface, a thick brittle IMC is layer formed at the interface, which makes cracks easy to initiate and expand. Otherwise, the losses of indium and tin contents in the LMTA during the interfacial reaction will make the melting point of the TIM layer increase, and so, the TIM layer will not melt at the operating temperature.
基金supported by the National Natural Science Foundation of China,China(No.51874047)the Key Science and Technology Project of Changsha City,China(No.kq2102005)+1 种基金the Special Fund for the Construction of Innovative Province in Hunan Province,China(No.2020RC3038)the Changsha City Fund for Distinguished and Innovative Young Scholars,China(No.kq1802007)。
文摘Thermal interface materials(TIMs)play a vital role in the thermal management of electronic devices and can significantly reduce thermal contact resistance(TCR).The TCR between the solid–liquid contact surface is much smaller than that of the solid–solid contact surface,but conventional solid–liquid phase change materials are likely to cause serious leakage.Therefore,this work has prepared a new formstable phase change thermal interface material.Through the melt blending of paraffin wax(PW)and low-density polyethylene(LDPE),the stability is improved and it has an excellent coating effect on PW.The addition of aluminum(Al)powder improves the low thermal conductivity of PW/LDPE,and the addition of 15wt%Al powder improves the thermal conductivity of the internal structure of the matrix by 67%.In addition,the influence of the addition of Al powder on the internal structure,thermal properties,and phase change behavior of the PW/LDPE matrix was systematically studied.The results confirmed that the addition of Al powder improved the thermal conductivity of the material without a significant impact on other properties,and the thermal conductivity increased with the increase of Al addition.Therefore,morphologically stable PW/LDPE/Al is an important development direction for TIMs.
基金supported by the National Natural Science Foundation of China (62075006)the National Key R&D Program of China (2018YFB1500200)。
文摘Interface engineering is proved to be the most important strategy to push the device performance of the perovskite solar cell(PSC) to its limit, and numerous works have been conducted to screen efficient materials. Here, on the basis of the previous studies, we employ machine learning to map the relationship between the interface material and the device performance, leading to intelligently screening interface materials towards minimizing voltage losses in p-i-n type PSCs. To enhance the explainability of the machine learning models, molecular descriptors are used to represent the materials. Furthermore,experimental analysis with different characterization methods and device simulation based on the drift-diffusion physical model are conducted to get physical insights and validate the machine learning models. Accordingly, 3-thiophene ethylamine hydrochloride(Th EACl) is screened as an example, which enables remarkable improvements in VOCand PCE of the PSCs. Our work reveals the critical role of datadriven analysis in the high throughput screening of interface materials, which will significantly accelerate the exploration of new materials for high-efficiency PSCs.
基金supported by the Fundamental Research Funds for the Central Universities (FRF-BR-10-007A and FRF-AS-09-001A)the National Natural Science Foundation of China (10872104)
文摘Thermal contact resistance plays a very important role in heat transfer efficiency and thermomechanical coupling response between two materials,and a common method to reduce the thermal contact resistance is to fill a soft interface material between these two materials.A testing system of high temperature thermal contact resistance based on INSTRON 8874 is established in the present paper,which can achieve 600 C at the interface.Based on this system,the thermal contact resistance between superalloy GH600 material and three-dimensional braid C/C composite material is experimentally investigated,under different interface pressures,interface roughnesses and temperatures,respectively.At the same time,the mechanism of reducing the thermal contact resistance with carbon fiber sheet as interface material is experimentally investigated.Results show that the present testing system is feasible in the experimental research of high temperature thermal contact resistance.
基金financially supported by the National Natural Science Foundation of China(Nos.52373042 and 52103091)the National Key Research and Development Project of China(No.2022YFB3806900)the International Visiting Program for Excellent Young Scholars of SCU。
文摘Effective thermal transport across solid-solid interfaces which is essential in thermal interface materials(TIMs),necessitates both optimal thixotropy and high thermal conductivity.The role of filler surface modification,a fundamental aspect of TIM fabrication,in the influence of these properties is not fully understood.This study employs the use of a silane coupling agent(SCA)to modify alumina,integrating experimental approaches with molecular dynamics simulations,to elucidate the interface effects on thixotropy and thermal conductivity in polydimethylsiloxane(PDMS)-based TIMs.Our findings reveal that the variations of SCAs modify both interface binding energy and transition layer thickness.The interface binding energy restricts macromolecular segmental relaxation near the interface,hindering desirable thixotropy and bond line thickness.On the contrary,the thickness of the transition layer at the interface positively influences thermal conductivity,facilitating the transport of phonons between the polymer and filler.Consequently,selecting an optimal SCA allows a balance between traditionally conflicting goals of high thermal conductivity and minimal bond line thickness,achieving an impressively low interface thermal resistance of just 2.45-4.29 K·mm^(2)·W^(-1)at275.8 kPa.
基金This work was supported by the National Natural ScienceFoundationofChina(No.U22B2066,No.12064044)the Major Science and Technology Projects of Anhui Province(No.202103a05020016)+1 种基金the open competition project to select the best candidates to undertake major science and key research projectsofTonglingcity,AnhuiProvince(No.202101JB002)A proportion of this work was supported by the High Magnetic Field Laboratory of Anhui Province and Academician workstation of Hangzhou Xingyu Carbon Environmental Tech Co.,Ltd.,and the Hefei Institutes of Physical Science Director's Fund(No.YZJJ-GGZX-2022-01).
文摘The growing concern about thermal conductivityand electromagnetic shielding inelectronic equipment has promoted the development of interfacial film materials.In this work,polyvinylidene fluoride(PVDF)/graphene composite films with different graphene contents were fabricated by high-energy ball milling,cold isostatic pressing,scraping and coating,successively.High-energy ball milling is beneficial to the dispersion of graphene powder,while cold isostatic pressing can greatly enhance thermal conductivity and mechanical strength by reducing the voids in the film and increasing the contact area of graphene sheets.The thermal conductivity,tensile strength and electromagnetic shielding properties of the films were carefully investigated and compared.It was demonstrated that the thermal conductivity increased from 0.19 W·m^(-1).K^(-1) for pure PVDF to 103.9 W·m^(-1).K^(-1)for the composite film with PVDF:graphene=1:3.Meanwhile the electromagnetic shielding efficiency can reach 36.55 dB.The prepared PVDF/graphene composite films exhibit outstanding overall performance and have the potential for practical applications.
基金flnancial support by the National Natural Science Foundation of China (52102055, 5227020331, 52075527)National Key R&D Program of China (2017YFB0406000 and 2017YFE0128600)+8 种基金the Project of the Chinese Academy of Sciences (XDC07030100, XDA22020602, ZDKYYQ20200001 and ZDRW-CN-2019-3)CAS Youth Innovation Promotion Association (2020301)Science and Technology Major Project of Ningbo (2021Z120, 2021Z115, 2022Z084, 2018B10046 and 2016S1002)the Natural Science Foundation of Ningbo (2017A610010)Foundation of State Key Laboratory of Solid lubrication (LSL-1912)China Postdoctoral Science Foundation (2020M681965, 2022M713243)National Key Laboratory of Science and Technology on Advanced Composites in Special Environments (6142905192806)K.C. Wong Education Foundation (GJTD-2019-13)the 3315 Program of Ningbo for financial support
文摘Developing advanced thermal interface materials(TIMs)to bridge heat-generating chip and heat sink for constructing an efficient heat transfer interface is the key technology to solve the thermal management issue of high-power semiconductor devices.Based on the ultra-high basal-plane thermal conductivity,graphene is an ideal candidate for preparing high-performance TIMs,preferably to form a vertically aligned structure so that the basal-plane of graphene is consistent with the heat transfer direction of TIM.However,the actual interfacial heat transfer efficiency of currently reported vertically aligned graphene TIMs is far from satisfactory.In addition to the fact that the thermal conductivity of the vertically aligned TIMs can be further improved,another critical factor is the limited actual contact area leading to relatively high contact thermal resistance(20-30 K mm^(2) W^(−1))of the“solid-solid”mating interface formed by the vertical graphene and the rough chip/heat sink.To solve this common problem faced by vertically aligned graphene,in this work,we combined mechanical orientation and surface modification strategy to construct a three-tiered TIM composed of mainly vertically aligned graphene in the middle and micrometer-thick liquid metal as a cap layer on upper and lower surfaces.Based on rational graphene orientation regulation in the middle tier,the resultant graphene-based TIM exhibited an ultra-high thermal conductivity of 176 W m^(−1) K^(−1).Additionally,we demonstrated that the liquid metal cap layer in contact with the chip/heat sink forms a“liquid-solid”mating interface,significantly increasing the effective heat transfer area and giving a low contact thermal con-ductivity of 4-6 K mm^(2) W^(−1) under packaging conditions.This finding provides valuable guidance for the design of high-performance TIMs based on two-dimensional materials and improves the possibility of their practical application in electronic thermal management.
基金financially supported by Sichuan Science and Technology Program (No.2022YFH0090)the Fundamental Research Funds for the Central Universities。
文摘Silicone rubber(SR) composites are most widely used as thermal interface materials(TIMs) for electronics heat dissipation. Thermal impedance as the main bottleneck limiting the performance of TIMs is usually neglected. Herein, the thermal impedance of SR composites loaded with different levels of hexagonal boron nitride(h-BN) as TIMs was elaborated for the first time by the ASTM D 5470 standard test and finite element analysis. It was found that elastic modulus and surface roughness of SR composites increased with the increase of h-BN content, indicating that the conformity was reduced. When the assembly pressure was 0.69 MPa, there existed an optimal h-BN content at which the contact resistance was minimum(0.39 K·cm^(2)·W^(-1)). Although the decreased bond line thickness(BLT) by increasing the assembly pressure was beneficial to reduce the thermal impedance, the proper assembly pressure should be selected to prevent the warpage of the contact surfaces and the increase in contact resistance, according to the compression properties of the SR composites. This study provides valuable insights into fabrication of high-performance TIMs for modern electronic device applications.
基金supported by the National Natural Science Foundation of China (Grant No. 51775299, 52075287)。
文摘Down to the road of miniaturization and high power density,the heat dissipation is becoming one of the critical factors restricting further development of advanced microelectronic devices.Traditional polymer-based thermal interface materials(TIMs) are not competitive for the high efficiency thermal management,mainly due to their low intrinsic thermal conductivity and high interface thermal resistance.Solder-based TIM is one of the best candidates for the next generation of thermal interface materials.This paper conducts a perspective review of the state of the art of solder TIM,including low melting alloy solder TIM,composite solder TIM and nanostructured solder TIM.The microstructure,process parameters,thermal performance and reliability of different TIMs are summarized and analyzed.The future trends of advanced TIMs are discussed.
基金financially supported by the Central Guidance on Local Science and Technology Develop-ment Fund Project of Hebei Province(Grant No.226Z4306G)the Natural Science Foundation of Hebei Province(Grant No.F2023201005)+4 种基金the National Key Research and Development Program of China(Grant No.2017YFA0206600)the National Natural Science Foundation of China(Grant Nos.21922505,21773045)the CAS Instrument Develop-ment Project(Grant No.YJKYYQ20190010)the Strategic Priority Research Program of Chinese Academy of Sciences(Grant No.XDB36000000)CAS-NST Joint Research Projects(Grant No.163GJHZ2023017MI).
文摘Organic solar cells(OSCs)have attracted attention due to their lightweight nature,flexibility,and facile preparation using solution-based methods.Their efficiency has been further elevated by the rapid advancement of nonfullerene materials,achieving individual cell efficiencies that surpass 19%.Hence,the stability of nonfullerene solar cell production must be scrutinized.The stability of the cathode interface layer significantly impacts the overall stability of OSC devices.PFN-Br,a commonly employed cathode interface material,is susceptible to degradation due to its sensitivity to environmental humidity,consequently compromising the device stability.In this study,we introduce fluorescent dye molecules,rhodamine 101,as cathode interface layers in OSCs to establish device stability and assess their universality.A comparative investigation of rhodamine 101 and PFN-Br devices demonstrates the former’s distinct advantages in terms of thermal stability,photostability,and storage stability even without encapsulation,particularly in an inert environment.By employing the Kelvin probe,we compare the work function of different cathode interface films and reveal that the work function of the rhodamine 101 interface material remains relatively unaffected by environmental factors.As a consequence,the device performance stability is significantly enhanced.The application of such fluorescent dye molecules extends the scope of cathode interface layers,amplifies device stability,and propels industrialization.
文摘The continuous miniaturization and high-power development of electronic devices have given rise to severe interface thermal issues,which urgently demand highly thermally conductive thermal interface materials(TIMs)to eliminate excessive heat accumulation and ensure the normal operation of devices[1].
基金supported by the National Natural Science Foundation of China(grant no.62304082)the National Key Research and Development Program of China(grant no.2020YFA0715000)the Natural Science Foundation of Hubei Province,China(grant no.2023AFB087).
文摘With the rapid development of artificial intelligence(AI)and big data technologies,electronic devices are evolving toward higher integration and power density,posing severe challenges for thermal dissipation.High-performance thermal interface materials(TIMs)used for minimizing the interfacial thermal resistance between the heater and heat sink are key to achieving efficient thermal management of electronic devices.To date,significant progress has been made in achieving high thermal conductivity by constructing oriented structures in TIMs.In this review,we systematically summarize and discuss the preparation methods for the design of TIMs with oriented structure.Furthermore,we particularly review the recent advancements in improving thermal contact resistance in oriented TIMs and emphasize that when the intrinsic thermal conductivity of the TIM is sufficiently high,thermal contact resistance becomes the primary bottleneck in heat dissipation.Finally,we outline the fundamentals of TIMs,the challenges,and potential directions associated with orientation structural design and practical applications,aiming to provide insights into the development of highperformance TIMs.
基金supported by the Shandong Provincial Natural Science Foundation(Grant No.ZR2020LFG007)Shandong Province Funds for Local Scientific and Technological Development under the Guidance of the Central Government(Grant No.YDZX2023037).
文摘Boron nitride nanoflakes(BNNF)are rendered as ideal thermal conductivity fillers for thermal interface materials(TIMs)due to their ultrahigh thermal conductivity(TC)and superior electronic insulation.However,it is difficult to guarantee the high yield of well dispersed BNNF in the polymer matrix for industrial production.Herein,we propose a novel“in-situ exfoliation”strategy to fabricate the thin BNNF via chemical bonding engineering.By enhancing theπ-πstacking between the inclusion and matrix,the average thickness of the BN is efficiently reduced during the three-roll mixing process.The as-prepared BNNF composite presents ultrahigh in-plane TC(10.58 W·m^(−1)·K^(−1))with 49.5%(in mass)BN loading at 100 parts per hundreds of rubber(phr)with simultaneously enhanced flexibility.Notably,the tensile strength,the initial thermal decomposition temperatures(T5%)and elongation at break of the composite can reach 4.94 MPa,470.6℃and 98%,respectively.Our LED chip cooling tests validate the outstanding heat dissipation ability of the composites for TIM applications.Furthermore,this strategy also proves effective in exfoliating the graphite flakes,demonstrating excellent generalization capability.This work opens up a new avenue for developing the high-performance TIMs,showing huge potential in large-scale production.
基金supported by the National Natural Science Foundation of China(22109142,52102142,52403253)the Natural Science Foundation of Henan Province(232300421360).
文摘As an important component to connect the electron transport layer(ETL)and the cathode electrode,the cathode interface layer(CIL)is key to enhancing electron transport and suppressing metal electrode corrosion in inverted perovskite solar cells(PSCs).In this work,three D-A-D type cathode interface materials(DPP-PhN,DPP-F3N,and ffBT-F3N)are designed and synthesized employing dimethylamino-benzene or bis(dimethylamino)propyl-fluorene as electron donating(D)unit,and pyrrolo[3,4-c]-pyrrole-1,4-dione(DPP)or benzothiadiazole(BT)as electron accepting(A)unit for efficient inverted PSCs.The impact of variations in the A and D units on the energy levels,conductivity,interfacial dipoles,and carrier interfacial dynamics of CILs were systematically studied.On the one hand,DPP-F3N possesses the highest conductivity and the strongest interfacial dipole.On the other hand,the DPP-F3N is most favorable for forming ohmic contacts between the ETL and the cathode electrode to improve electron transport and prevent carrier recombination.As a result,the inverted PSCs using DPP-F3N as the CIL obtained the highest power conversion efficiency(PCE)of 25.19%.However,in terms of stability,the ffBT-F3N-based inverted PSCs show the best stability due to the strong interaction between the ffBT-F3N and the Ag electrode,which could effectively delay the corrosion of the Ag electrode.
基金the support of National Key Project of Research and Development Plan No.2018YFB0703600NSFC program No.51872133 and 51572282Guangdong Innovative and Entrepreneurial Research Team Program,No.2016ZT06G578.
文摘The past years has observed a significantly boost of the thermoelectric materials in the scale of thermoelectric figure-of-merit,i.e.ZT,because of its promising application to harvest the widely distributed waste heat.However,the simplified thermoelectric materials'performance scale also shifted the focus of thermoelectric energy conversion technique from devices-related efforts to materials-level works.As a result,the thermoelectric devices-related works didn't get enough attention.The device-level challenges behind were kept unknown until recent years.However,besides the thermoelectric materials properties,the practical energy conversion efficiency and service life of thermoelectric device is highly determined by assembling process and the contact interface.In this perspective,we are trying to shine some light on the device-level challenge,and give a special focus on the thermoelectric interface materials(TEiM)between the thermoelectric elements and electrode,which is also known as the metallization layer or solder barrier layer.We will go through the technique concerns that determine the scope of the TEiM,including bonding strength,interfacial resistance and stability.Some general working principles are summarized before the discussion of some typical examples of searching proper TEiM for a given thermoelectric conversion material.
文摘As electronic devices continue to evolve toward miniaturization and integration,traditional thermal interface materials(TIMs)are no longer able to meet the ever-tougher thermal management challenges.Owing to their high thermal conductivity and excellent conformability within a highly confined space,liquid metals have great potential for advanced thermal management in various cutting-edge devices and have become a key candidate for next-generation high-performance TIMs.In addition to already known materials,such as liquid metal alloy TIMs,particle-filled liquid metal TIMs,and liquid metal-filled TIMs,more TIMs are still being developed.This review presents a systematic classification of the liquid metal TIMs developed thus far,interprets the fundamental mechanisms underlying material innovation and in-situ heat transfer enhancement,and comparatively evaluates their respective advantages and shortcomings.Subsequently,a series of representative theoretical models for characterizing the thermal conductivities of composites are summarized,and the limits of the thermal conductivity of liquid metal TIMs are predicted to guide practical R&D efforts.To address the urgent need for higher-performance TIMs to overcome future thermal management challenges of electronic devices,a roadmap is outlined for the development of high-performance liquid metal TIMs,and a strategy for running these technologies is demonstrated.
基金supported by the National Natural Science Foundation of China(No.52076041)the Natural Science Foundation of Jiangsu Province(No.BK20200371)the Nanjing Carbon Peak and Carbon Neutrality Science and Technology Innovation Project(No.202211009)。
文摘Vertically aligned carbon nanotubes arrays(VACNTs)are a promising candidate for the thermal interface material(TIM)of next-generation electronic devices due to their attractive thermal and mechanical properties.However,the environment required for synthesizing VACNTs is harsh and severely incompatible with standard device packaging processes.VACNTs’extremely low in-plane thermal conductivity also limits its performance for cooling hot spots.Here,using a transfer-and-encapsulate strategy,a two-step soldering method is developed to cap both ends of the VACNTs with copper microfoils,forming a standalone Cu-VACNTs-Cu sandwich TIM and avoiding the need to directly grow VACNTs on chip die.This new TIM is fully compatible with standard packaging,with excellent flexibility and high thermal conductivities in both in-plane and through-plane directions.The mechanical compliance behavior and mechanism,which are critical for TIM applications,are investigated in depth using in situ nanoindentation.The thermal performance is further verified in an actual light emitting diode(LED)cooling experiment,demonstrating low thermal resistance,good reliability,and achieving a 17℃ temperature reduction compared with state-of-the-art commercial TIMs.This study provides a viable solution to VACNTs’longstanding problem in device integration and free-end contact resistance,bringing it much closer to application and solving the critical thermal bottleneck in next-generation electronics.
基金This work was supported by the National Key Research and Development Program of China(No.2020YFB040176)National Natural Science Foundation of China(No.52073300 and 62104161)+3 种基金the Youth Innovation Promotion Association of the Chinese Academy of Sciences(2019354)Guangdong Province Key Field R&D Program Project(No.2020B010190004),Shenzhen Science and Technology Research Funding(No.JCYJ20200109114401708)Key Project of Science and Technol-ogy of Changsha(kq2102005)Guangdong Provincial Key Laboratory(2014B030301014).
文摘The emerging applications of composite gels as thermal interface ma-terials(TIMs)for chip heat dissipation in intelligent vehicle and wear-able devices require high thermal conductivity and remarkable damp-ing properties.However,thermal conductivity and damping proper-ties are usually correlated and coupled each other.Here,inspired by Maxwell theory and adhesion mechanism of gecko’s setae,we present a strategy to fabricate polydimethylsiloxane-based composite gels in-tegrating high thermal conductivity and remarkable damping prop-erties over a broad frequency and temperature range.The multiple relaxation modes of dangling chains and the dynamic interaction be-tween the dangling chains and aluminum fillers can efficiently dis-sipate the vibration energy,endowing the composite gels with ultra-high damping property(tanδ>0.3)over a broad frequency(0.01-100 Hz)and temperature range(-50-150°C),which exceeds typi-cal state-of-the-art damping materials.The dangling chains also com-fort to the interfaces between polymer matrix and aluminum via van der Waals interaction,resulting in high thermal conductivity(4.72±0.04 W m-1 K-1).Using the polydimethylsiloxane-based composite gel as TIMs,we demonstrate effective heat dissipation in chip oper-ating under vigorous vibrations.We believe that our strategy could be applied to a wide range of composite gels and lead to the devel-opment of high-performance composite gels as TIMs for chip heat dissipation.
