Thermal Rectification Research Articles

CFD analysis and optimization of thermal stratification in a Thermal Diode Tank (TDT)

Thermal stratification is a common and natural phenomenon in energy storage tanks. This paper presents a Computational Fluid Dynamics (CFD) analysis of thermal stratification within a novel cold energy storage, termed a Thermal Diode Tank (TDT). The TDT is a well-insulated water tank equipped with heat pipes for unidirectional heat transfer from water to the ambient air. When integrated into a Refrigeration and Air-conditioning (RAC) system, it provides cooling water to reduce the condensing temperature. The research problem revolves around the impact of thermal stratification on TDT performance and the identification of the optimal TDT structure when thermal stratification is present. Therefore, this study aims to employ CFD to simulate temperature profiles within a TDT, both with and without an obstacle. With validated models, parametric analysis has been conducted to determine the optimal TDT structure. Several design parameters have been investigated, including tank orientation, heat transfer capacity, the ratio of obstacle axial height to TDT height (ho/H), and the ratio of obstacle hole diameter to TDT diameter (do/D). Key findings reveal that a vertical tank orientation is more conducive to improving the TDT assisted RAC system performance than a horizontal one. Increasing the TDT's heat transfer capacity also positively contributes to the system performance. Parameters of an optimal TDT structure include a ho/H ratio of approximately 0.43 and a do/D ratio of 0.4. It is found that the do/D ratio should be at least 0.15 to obtain positive stratification. Furthermore, the presence of thermal stratification can increase the system's Coefficient of Performance (COP) by up to 10 %.

Nonequilibrium thermal rectification at the junction of harmonic chains.

A thermal diode or rectifier is a system that transmits heat or energy in one direction better than in the opposite direction. We investigate the influence of the distribution of energy among wave numbers on the diode effect for the junction of two dissimilar harmonic chains. An analytical expression for the diode coefficient, characterizing the difference between heat fluxes through the junction in two directions, is derived. It is shown that the diode coefficient depends on the distribution of energy among wave numbers. For an equilibrium energy distribution, the diode effect is absent, while for non-equilibrium energy distributions the diode effect is observed even though the system is harmonic. We show that the diode effect can be maximized by varying the energy distribution and relative position of spectra of the two harmonic chains. Conditions are formulated under which the system acts as an ideal thermal rectifier, i.e., transmits heat only in one direction. The results obtained are important for understanding the heat transfer in heterogeneous low-dimensional nanomaterials.

Competing mechanisms govern the thermal rectification behavior in semi-stochastic polycrystalline graphene with graded grain-size distribution

Thermal rectifiers are devices that have different thermal conductivities in opposing directions of heat flow. The realization of practical thermal rectifiers relies significantly on a sound understanding of the underlying mechanisms of asymmetric heat transport, and two-dimensional materials offer a promising opportunity in this regard owing to their simplistic structures together with a vast possibility of tunable imperfections. However, the in-plane thermal rectification mechanisms in 2D materials like graphene having directional gradients of grain sizes have remained elusive. In fact, understanding the heat transport mechanisms in polycrystalline graphene, which are more practical to synthesize than large-scale single-crystal graphene, could potentially allow a unique opportunity, in principle, to combine with other defects and designs for effective optimization of thermal rectification. In this work, we investigate the thermal rectification behavior in periodic atomistic models of polycrystalline graphene whose grain arrangements were generated semi-stochastically to have different gradient grain-density distributions along the in-plane heat flow direction. We employ the centroidal Voronoi tessellation technique to generate realistic grain boundary structures for graphene, and the non-equilibrium molecular dynamics simulations method is used to calculate the thermal conductivities and rectification values. Additionally, detailed phonon characteristics and propagating phonon spatial energy densities are analyzed based on the fluctuation-dissipation theory to elucidate the competitive interplay between two underlying mechanisms, namely, (1) propagating phonon coupling and (2) temperature-dependence of thermal conductivity that determine the degree of asymmetric heat flow in graded polycrystalline graphene.

Simulation of a radiation-enhanced thermal diode tank (RTDT) assisted refrigeration and air-conditioning (RAC) system using TRNSYS

The increasing demands for refrigeration and cooling have led to higher energy consumption and greenhouse gas emissions of Refrigeration and Air-conditioning (RAC) systems. To tackle this global challenge, a Radiation-enhanced Thermal Diode Tank (RTDT) has been proposed as an innovative and sustainable condenser-cooling approach to assist the RAC system to save energy. The RTDT is a passive cooling device that utilises a Radiation-enhanced Heat Pipe (RHP) to discharge heat in one direction, i.e., from the interior of a heat-insulated water tank to the surrounding area. In this paper, TRNSYS simulation was used to conduct a case study comparing the performance of the RTDT assisted RAC (RTDT-RAC) system with a reference Air-cooled RAC system under identical ambient conditions in Adelaide, Australia. The findings show that the RTDT-RAC system can save up to 40 % energy compared with the reference RAC system, with an increased Coefficient of Performance (COP) of 5.34. Moreover, a parametric analysis has also been conducted to study the impacts of weather conditions or regions, room temperature setpoints and RHP radiative surface areas on the RTDT-RAC system's performance. The results of the parametric analysis indicate that the regions with larger day and night ambient temperature differences demonstrate better energy-savings. Both a higher room temperature setpoint and an increased RHP radiative surface area can increase the energy-savings effectively. For a 50 m3 RTDT, to achieve energy-savings, the RHP radiative surface area is found to be at least 2.2 m2, while the optimal value is about 5 m2.

Thermal transport of graphene-C3B superlattices and van der Waals heterostructures: a molecular dynamics study

Two-dimensional (2D) materials have attracted more and more attention due to their excellent properties. In this work, we systematically explore the heat transport properties of Graphene-C3B (GRA-C3B) superlattices and van der Waals (vdW) heterostructures using molecular dynamics method. The effects of interface types and heat flow directions on the in-plane interfacial thermal resistance (ITRip) are analyzed. Obvious thermal rectification is detected in the more energy stable interface, GRA zigzag-C3B zigzag (ZZ) interface, which also has the minimum value of ITRip. The dependence of the superlattices thermal conductivity (k) of the ZZ interface on the period length (l p ) is investigated. The results show that when the l p is 3.5 nm, the k reaches a minimum value of 35.52 W m−1 K−1, indicating a transition stage from coherent phonon transport to incoherent phonon transport. Afterwards, the effects of system size, temperature, coupling strength and vacancy defect on the out-of-plane interfacial thermal resistance (ITRop) are evaluated. With the increase of temperature, coupling strength and vacancy defect, ITRop are found to reduce effectively due to the enhanced Umklapp phonon scattering and increased probability of energy transfer. Phonon density of states and phonon participation ratio is evaluated to reveal phonon behavior during heat transport. This work is expected to provide essential guidance for the thermal management of nanoelectronics based on 2D monolayer GRA and C3B.

Thermoelectric Generator Through Dual-Direction Thermal Regulation by Thermal Diodes for Waste Heat Harvesting.

Thermal energy harvesting provides an opportunity for multi-node systems to achieve self-power autonomy. Thermoelectric generators (TEGs), either by thermocouple arrangement with higher-aspect-ratios or thermoelectric films overlay, are limited by the small temperature difference and its short-duration (less than dozens of minutes), hindering the harvesting efficiency. Here, by introducing thermal diodes with dual-direction thermal regulation ability to optimize the heat flux path, the proposed TEGs exhibit enhanced power-supply capability with unprecedented long-duration (more than hours). In contrast with conventional TEGs with fixed-leg dimensions enabled single output, these compact-TEGs can supply up to fourteen output-channels for selection, the produced power ranges from 1.11 to 921.99µW, open circuit voltage ranges from 8.07 to 51.32mV, when the natural temperature difference is 53.84°C. Compared to the most recent TEGs, the proposed TEGs in this study indicate higher power (more than hundreds times) and much longer output duration (2.4-120 times) in a compact manner.

An advanced Photovoltaic Thermal Collector Storage Solar Water Heating based on planar liquid vapour thermal diode: Model-based design approach for the optimal energy performance assessment

The building sector is responsible for the highest portion of energy consumption and carbon dioxide emissions. To partly address this issue, the scientific community is placing greater emphasis on the utilization of Building Integrated Solar Systems (BISS) as a means of improving building thermophysics and decreasing primary energy demand. Within this framework, Integrated Collector Storage Solar Water Heaters (ICSSWH) have the potential to significantly decrease the costs associated with the installation and maintenance of building-integrated solar systems (BISS), all while optimizing the utilization of solar power. Nevertheless, ICSSWHs exhibit certain limitations in their capacity to retain thermal energy, particularly during nocturnal periods. One potential approach for enhancing the efficiency of ICSSWH collectors involves the integration of Thermal Diodes (TD), which have the capability to optimize heat absorption while minimizing heat retention. In this context, to advance the state-of-the-art in the field, this paper presents a novel dynamic simulation tool conceived to assess the performance of an innovative Hybrid Photovoltaic Thermal ICSSWH (the HyPVT), incorporating a cutting-edge Planar Liquid Vapour Thermal Diode (PLVTD), and purposely designed to be integrated into buildings’ envelope. By using the developed simulation tool, the performance of the proposed HyPVT collector concept is investigated with the aim of assessing its collection and retention efficiencies under different boundary and operating conditions. Furthermore, to show the effect of the Planar Liquid Vapour Thermal Diode (PLVTD) adoption, a comparative analysis is conducted between the proposed ICSSWH and a conventional one (without a thermal diode). Finally, the developed tool will be utilized in forthcoming research to determine the optimal device configuration through the utilization of a model-based design methodology.

Energy-Mass and Thermoelectric Characteristics of the Current Convertor, Made on the Devices of Plasma Electric Power Industry

In space power propulsion systems (SPPS) based on a low-voltage power source and high-voltage electric rocket thrusters, a current conversion system (CCS) is required. As one of the elements of promising high–temperature CCS, high-temperature plasma thermal emission valves (HPTV) of plasma electric power industry are considered – grid key elements (GKE) and high-voltage plasma thermal emission diodes (HVPTD). In the work, the modeling of the energy-mass characteristics of the CCS built on the GKE and HVPTD using heat pipes (HP) for cooling is carried out, the temperature conditions in which the minimum specific mass of the current converter is achieved are determined. The specific gravity values are determined. The results of the work can be used in the development of new high-temperature CCS space power propulsion systems for electrical power from tens to thousands of kilowatts.

Phonon Scattering Engineered Unconventional Thermal Radiation at the Nanoscale.

We show that engineering phonon scattering, such as through isotope enrichment and temperature modulation, offers the potential to achieve unconventional radiative heat transfer between two boron arsenide bulks at the nanoscale, which holds promise in applications for nonlinear thermal circuit components. A heat flux regulator is proposed, where the temperature window for stabilized heat flux exhibits a wide tunability through phonon scattering engineering. Additionally, we propose several other nonlinear thermal radiative devices, including a negative differential thermal conductance device, a temperature regulator, and a thermal diode, all benefiting from the design space enabled by isotope and temperature engineering of the phonon linewidth. Our work highlights the capability of temperature and isotope engineering in designing and optimizing nonlinear radiative thermal devices and demonstrates the potential of phonon engineering in thermal radiative transport.

Thermal boundary resistance and thermal rectification in VACNT arrays integrated with SnZn alloys

Thermal rectification (TR) phenomena in carbon nanotubes (CNTs) have been previously foreseen through theoretical predictions; however, its experimental realization in bulk CNT arrays remains relatively unexplored. Herein, we have synthesized vertically aligned carbon nanotube (VACNT) arrays of ∼ 4.5 mm in length on a 4-inch silicon wafer by a combined bubble-assisted chemical vapor deposition method. By integrating these VACNT arrays with SnZn alloys, we have successfully developed devices capable of functioning across a wide temperature range spanning from 200 °C to 400 °C. Notably, the thermal boundary resistances (TBR) between the VACNTs and SnZn alloy exhibit pronounced dependence on the alloy's composition, exhibiting variations ranging from 0.12 cm2KW−1 to 1.12 cm2KW−1. Of particular significance, the TBRs of Sn50Zn50/VACNT compounds in the forward direction were found to fall within the range of 0.63–0.98 cm2KW−1 in the temperature range from120 °C to 180 °C, while in the backward direction, they exhibited values in the range of 0.13–0.34 cm2KW−1. These contrasting TBR values highlight a marked thermal rectification performance with a substantial TR coefficient between 0.49 and 0.66. Our comprehensive investigation sheds valuable insights into the TR effects within VACNTs and metal/alloy interfaces, presenting a promising avenue for the development of future thermal logic circuits and thermal transistors.

Thermal rectification in mass-asymmetric one-dimensional anharmonic oscillator lattices with and without a ballistic spacer

In this work we perform a systematic analysis of various structural parameters that have influence on the thermal rectification effect, i.e. asymmetrical heat flow, and the negative differential thermal resistance —reduction of the heat flux as the applied thermal bias is increased— present in a one-dimensional, segmented mass-graded system consisting of a coupled nearest-neighbor harmonic oscillator lattice (ballistic spacer) and two diffusive leads (modeled by a substrate potential) attached to the lattice at both boundaries. At variance with previous works, we consider the size of the spacer as smaller than that of the leads. Also considered is the case where the leads are connected along the whole length of the oscillator lattice; that is, in the absence of the ballistic spacer. Upon variation of the system’s parameters it was determined that the performance of the device, as quantified by the spectral properties, is largely enhanced in the absence of the ballistic spacer for the small system-size limit herein considered.

PT‐Symmetry Enabled Spintronic Thermal Diodes and Logic Gates

AbstractDevices for performing computation and logic operations with low‐energy consumption are of key importance for environmentally friendly data processing and information technology. Here, a design for magnetic elements that use excess heat to perform logic operations is presented. The basic information channel is coupled non‐conductive magnetic stripes with a normal metal spacer. The thermal information signal is embodied in magnetic excitations and it can be transported, locally enhanced, and controllably steered by virtue of charge current pulses in the spacer. Functionality of essential thermal logic gates is demonstrated by material‐specific simulations. The operation principle takes advantage of the special material architecture with a balanced gain/loss mechanism for magnetic excitation which renders the circuit parity‐time symmetric with exceptional points tunable by the current strength in the spacer. Heat flow at these points can be enhanced, be non‐reciprocal, or may oscillate between the information channels enabling controlled thermal diode and thermal gate operations. The findings point to a new route for exploiting heat for useful work on the nanoscale.

Solid state thermal rectification by chemical pressure tuning of magnetic properties in perovskites

From an efficiency framework, waste heat generation and accumulation place significant limitations on how systems ultimately perform. Particularly, heat buildup leads to a significant loss of efficiency and subsequently system failure. In addition, current insulation and heat removal elements for supporting reliability and efficiency are robust and high power consumption systems that are based entirely on linear thermal elements instead of non-linear elements that would allow a unidirectional heat regulation process, thereby avoiding heat accumulation. In this sense, thermal rectifiers have recently attracted considerable interest due to their ability to manage heat unidirectionally. In this work, with the aim of exploring the potential of perovskites in thermal rectification, the magnon mediated thermal transport in the system La0.7Sr0.3Mn1–xCoxO3 (0 < x < 0.1) obtained by the solid-state ceramic route is investigated. Interestingly, results shows that thermal conductivity and Curie temperature substantially decreases with increasing of Co contents, which is attributed to the fact that positive chemical pressure is created due to smaller Co atoms take the place of some of the Mn atoms in the perovskite, shrinking the crystal structure. Taking advantage of those granted features, two-segment thermal diodes based on La0.7Sr0.3Mn1–xCoxO3/SiO2 have been implemented as a proof of concept devices. Experimental thermal transfer characteristics reveal that thermal diodes have markedly a nonlinear heat transport with rectification factors up to 2.3, meaning that devices control the heat flow via the deactivation of magnons through the Curie temperature; which in turn, controls accurately the on state of the device.

Low-frequency heat waves transport in graded Si–Ge alloys

In this work, we consider a rigid heat conductor graded material subjected to an oscillating thermal signal applied on its boundary. We use a recently proposed novel concept, the so-called spectral diffusivity, to characterize the response of the material to an externally applied variable temperature difference. The spectral diffusivity has the physical meaning of an effective transport coefficient. We found a frequency window between 10−2 and 102 Hz wherein the spectral diffusivity increases, showing a maximum. The transport equation was numerically solved to calculate the average heat flowing through the material. We found that it also increased having a maximum in the mentioned range of frequencies. We then investigated the thermal rectification of the material finding a maximum in the same frequency range. The thermal rectification, as well as the spectral diffusivity, improved as the inhomogeneity of the heat conductivity of the material was higher. The spectral diffusivity enables a more in-depth analysis of heat wave transfer, and it contributes to a better understanding of the material response in front of periodic thermal disturbances.

Far-Field Radiative Thermal Rectification Based on Asymmetric Emissivity.

This experimental study investigates thermal rectification via asymmetric far-field thermal radiation on a fused silica slab. An asymmetrical distribution of surface emissivity is created over the device by partially covering the fused silica with a 100 nm thick aluminum film. The slab is subjected to a thermal bias, and when this bias is reversed, a small temperature difference is observed between the different configurations. This temperature difference arises from the difference in emissivity between the aluminum layer and fused silica, resulting in the transfer of thermal energy to the surrounding environment through radiation. Experimental findings are supported by finite element simulations, which not only confirm the measured values but also provide valuable insights into the rectification efficiency of the system. The rectification efficiency is found to be approximately 50% at room temperature for a thermal bias of 140 K. Simulations, which are performed by considering different environmental conditions experienced by the radiation and free convection processes, provide further insight into the underlying thermal rectification mechanism. These simulations consider an environmental temperature of 4 K for thermal radiation and an ambient temperature of 294 K for free convection and reveal an enhanced rectification effect with a rectification efficiency up to 600% when a thermal bias of 195 K is applied. This result emphasizes the significance of considering both convection and radiation in the thermal management and rectification of asymmetric systems. The outcomes of this study further our understanding of the thermal rectification phenomenon. They also show the importance of system asymmetry, emissivity disparities, environmental conditions, and the interplay between convection and radiation. Furthermore, the findings have implications for heat transfer and rectification in asymmetric systems, offering potential applications in areas such as energy harvesting, thermal management, and heat transfer optimization in electronic devices.

Thermal rectification through the topological states of asymmetrical length armchair graphene nanoribbons heterostructures with vacancies

We present a theoretical investigation of electron heat current in asymmetrical length armchair graphene nanoribbon (AGNR) heterostructures with vacancies, focusing on the topological states (TSs). In particular, we examine the 9-7-9 AGNR heterostructures where the TSs are well-isolated from the conduction and valence subbands. This isolation effectively mitigates thermal noise of subbands arising from temperature fluctuations during charge transport. Moreover, when the TSs exhibit an orbital off-set, intriguing electron heat rectification phenomena are observed, primarily attributed to inter-TS electron Coulomb interactions. To enhance the heat rectification ratio (η Q ), we manipulate the coupling strengths between the heat sources and the TSs by introducing asymmetrical lengths in the 9-AGNRs. This approach offers control over the rectification properties, enabling significant enhancements. Additionally, we introduce vacancies strategically positioned between the heat sources and the TSs to suppress phonon heat current. This arrangement effectively reduces the overall phonon heat current, while leaving the TSs unaffected. Our findings provide valuable insights into the behavior of electron heat current in AGNR heterostructures, highlighting the role of topological states, inter-TS electron Coulomb interactions, and the impact of structural modifications such as asymmetrical lengths and vacancy positioning. These results pave the way for the design and optimization of graphene-based devices with improved thermal management and efficient control of electron heat transport.

Dirac semimetal-assisted near-field radiative thermal rectifier and thermostat based on phase transition of vanadium dioxide.

The near-field thermal radiation has broad application prospects in micro-nano-scale thermal management technology. In this paper, we report the Dirac semimetal-assisted (AlCuFe quasicrystal) near-field radiative thermal rectifier (DSTR) and thermostat (DST), respectively. The DSTR is made of a Dirac semimetal-covered vanadium dioxide (VO2) plate and silicon dioxide (SiO2) plate separated by a vacuum gap. The left and right sides of DST are consisted of the SiO2 covered with Dirac semimetal, and the intermediate plate is the VO2. The strong coupling of the surface electromagnetic modes between the Dirac semimetal, SiO2, and insulating VO2 leads to enhance near-field radiative transfer. In the DSTR, the net radiative heat flux of VO2 in the insulating state is much larger than that in metallic state. When the vacuum gap distance d=100 nm, Fermi level EF=0.20 eV, and film thickness t=12 nm, the global rectification factor of DSTR is 3.5, which is 50% higher than that of structure without Dirac semimetal. In the DST, the equilibrium temperature of the VO2 can be controlled accurately to achieve the switching between the metallic and insulating state of VO2. When the vacuum gap distance d=60 nm, intermediate plate thickness δ=30 nm, and film thickness t=2 nm, with the modulation of Fermi level between 0.05-0.15 eV, the equilibrium temperature of VO2 can be controlled between 325-371 K. In brief, when the crystalline state of VO2 changes between the insulating and metallic state with temperature, the active regulation of near-field thermal radiation can be realized in both two-body and three-body parallel plate structure. This work will pave a way to further improve performance of near-field radiative thermal management and modulation.

The energy saving performance of the thermal diode composite wall in different climate regions

The effective management of energy consumption during building operations continues to be of utmost importance. The role of a building's envelope in regulating energy consumption is critical. However, traditional building insulation systems often struggle to maintain optimal indoor temperatures in the face of fluctuating external temperatures. Solar energy, for instance, can easily penetrate a room through windows during the cooling season, leading to increased energy consumption. Similarly, heat dissipates easily during the heating season. To address these challenges, thermal diode composite walls with unidirectional heat transfer offer a groundbreaking approach to simplifying the design of thermal management systems. The thermal diode composite wall effectively controls heat conduction, convection, and radiation through the implementation of different functional layers. By regulating the heat flux through the building envelope, this technology significantly reduces energy consumption during building operations while maintaining a stable indoor temperature. To evaluate the performance of an adaptable thermal diode composite wall, we designed, implemented, and conducted tests on a thermal diode composite wall building. The results of the study demonstrate substantial energy savings, ranging from 3.5% to 69.3% for annual operation in various regions, with better performance observed in colder regions. In the forward heat conduction mode, the temperature difference between the inside and outside wall surfaces reached a maximum of 20.99 K, while in the reverse mode, it reached −35.67 K. These findings highlight the remarkable potential of thermal diode composite walls in significantly improving the energy efficiency and comfort of buildings. Consequently, the adoption of thermal diode composite walls presents numerous opportunities for the development of low-carbon buildings.

Performance Simulation Model of a Radiation-Enhanced Thermal Diode Tank-Assisted Refrigeration and Air-Conditioning (RTDT-RAC) System: A Novel Cooling System

This paper presents a novel technology to improve the energy efficiency of refrigeration and air-conditioning (RAC) systems by applying a condenser cooling approach. The approach is based on the integration of an innovative radiation-enhanced thermal diode tank (RTDT) with a RAC system. The thermal diode tank (TDT), consisting of heat pipes and an insulated water tank, is a passive device to generate cooling water at a minimum night ambient temperature. When the radiation-enhanced heat pipe (RHP) is equipped with the TDT, it becomes an RTDT, which could theoretically lower the water temperature below the ambient temperature. In this study, a radiation-enhanced thermal diode tank (RTDT) is proposed to supply cooling water to the RAC system. Simulation models for the proposed RTDT-assisted RAC (RTDT-RAC) system are developed in order to investigate the impacts of the tank size to cooling capacity (TS/Qc) ratio, day/night ambient temperature fluctuations on the system’s coefficient of performance (COP) and the energy saving percentage (ESP). The results show that a greater day/night ambient temperature difference and a larger TS/Qc value can both enhance the COP and ESP of the RTDT-RAC system. The optimal and threshold TS/Qc values were 1 m3/kW and 0.18 m3/kW, respectively. These findings demonstrate the potential of the RTDT-RAC system to achieve significant energy savings and provide valuable insights for the design and optimization of an RTDT-RAC system.

A cellulose-based membrane with temperature regulation and water transportation for thermal management applications

Thermal management materials are widely employed in the construction and textile industries due to their non-energy input and the ability to precisely adjust the temperature. However, the application of thermal management technique toward sustainable agriculture is still challenging due to the complex environment. Herein, a coupled insulation system with highly asymmetric thermal conductivity and unidirectional water penetration is developed by using the integration of thermal management and water diodes technologies. The hierarchical membrane shows asymmetric thermal conductivity of carbonized cellulose layer (CCL, 0.64 W m−1 K−1) and Al2O3/cellulose layer (ACL, 0.16 W m−1 K−1), and good moisture permeability owing to the anisotropic wettability of the material and hierarchical structure design. Thermal management performance revealed that compared with PET and cellulose membrane, the membrane temperature increased by 4.1 °C and 1.3 °C, respectively, resulting in a decrease in greenhouse heat dissipation. Besides, benefitting from the efficient photothermal conversion performance of carbonized cellulose, the outside can rapidly warm up to 42 °C under 120 W/m2 sun radiation, providing a suitable growth temperature for crops. Meanwhile, unidirectional water penetration achieved in the 60 s not only enables the membrane to maintain long-term and effective insulation, but also ensures the demand of crops for water during drought conditions. Furthermore, the anti-flaming property broadens the range of applications, reducing damage in an emergency such as a fire. The demonstrated membrane can potentially replace the commercial plastic-based greenhouse materials, and the gradient and bilayer design open a new avenue for sustainable thermal management application.