An all-weather radiative human body cooling textile

Radiative cooling textiles dissipate human body heat without any energy input, providing a sustainable means for personal thermal management. However, there is still a lack of textile materials to support efficient cooling in varied outdoor and indoor environments. Here we show a polyoxymethylene (POM) nanotextile design that not only achieves selective emission in the atmospheric window (8–13 μm) but also shows transmission in the remaining mid-infrared wavebands and reflection of sunlight (0.3–2.5 μm). As a result, the POM textile achieves efficient radiative human body cooling both outdoors (under sunny and cloudy conditions) and indoors (0.5–8.8 °C lower than typical textiles). Moreover, the textile design shows favourable wearability and outperforms its commercial counterparts when used as protective clothing. The POM material provides both indoor and outdoor human body cooling and introduces new possibilities in the rational design of next-generation smart textiles and other applications supporting sustainability. Radiative cooling textiles provide a sustainable means for personal thermal management. Here the nano-textile design realizes an unprecedented combination of human body cooling in both indoor and outdoor conditions without compromising wearability.

Widely used active cooling systems such as air conditioners consume large amounts of energy, accounting for ~15% of global electricity consumption 1,2 .Passive radiative cooling is an emerging cooling technology that operates by radiative heat transfer into surrounding environments with a lower temperature and even into the cold outer space (nearly 3 K) through the atmospheric window (8-13 μm) [3][4][5] .Radiative cooling technology has shown great potential for personal thermal management because radiative heat transfer is the primary heat dissipation pathway for human bodies, which accounts for 40-60% of the total heat transfer from a human body (Supplementary Fig. 1) 6,7 .
Various radiative cooling textile materials have been developed for human body cooling in different environments, including indoors and outdoors [8][9][10][11][12][13][14][15] .Depending on their cooling mechanism, radiative cooling textiles can be categorized into two groups, namely, transmission-type textiles, which are mainly used in indoor environments, and emission-type textiles, which are usually used outdoors (Supplementary Fig. 2).The former category of textiles, such as nanoporous polyethylene (PE) based textiles, is transparent to human body radiation in the mid-infrared (MIR) waveband (Supplementary Fig. 2a,c) and is opaque to visible light 8,12,16,17 .Thus, human bodies (~34 °C) can be cooled by directly dissipating heat through this textile into the surroundings; the method has thus been proven to be the optimal choice for indoor radiative human body cooling 8,18 .In contrast, the emission-type textiles emit human heat into the cold outer space via the atmospheric window (8-13 μm) (Supplementary Figs.2b,d).The materials used are usually polymers or polymer-dielectric composites containing strong molecular vibrations and hierarchically designed nanostructures 14,15,[19][20][21] .Direct heat exchange with outer space and high solar reflection result in emission-type radiative cooling materials with the possibility of achieving sub-ambient cooling effects under strong direct sunlight [22][23][24][25][26][27][28][29][30][31][32] , making them an ideal choice for outdoor human body cooling.
It would be ideal if radiative cooling textiles allow for effective human body cooling for both outdoor and indoor environments.

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https://doi.org/10.1038/s41893-023-01200-xsteady-state heat transfer models (Supplementary Figs. 3 and 4 and Supplementary Tables 1 and 2).The results showed that in outdoor environments under strong sunlight (800 W m −2 ), the adaptive-type textile enabled a notably lower skin surface temperature than transmission-type (25.7 °C lower) and emission-type (4.2 °C lower) textiles (Fig. 1c,d).This occurs due to the higher solar reflectance of our textile design compared to the transmission-type textile and the additional cooling effect by the non-window MIR transmission compared to the emission-type textile.For indoor environments, the skin surface temperature with the adaptive-type textile was slightly higher (0.8 °C) than that with transmission-type textiles but was notably lower (2.5 °C) than that with emission-type textiles (Fig. 1c,e).This indicates that the current textile has a cooling performance almost as good as that of the transmission-type textile and much better than that of the emission-type textile, benefiting from its high MIR transmission (61%).As a result, the POM textile showed good performance in both outdoor and indoor environments.Similar conclusions are reached at different ambient temperatures (Supplementary Text 2 and Supplementary Fig. 5), high humidity conditions (Supplementary Text 3 and Supplementary Fig. 6) and cloudy outdoor environments (Supplementary Text 4 and Supplementary Fig. 7) or when compared with other types of emission-transmission model (Supplementary Text 5 and Supplementary Figs. 8 and 9).

Material design and characterization
Emission and transmission by organic materials in the MIR region (corresponding to the main human radiation waveband) intrinsically depend on their molecular bonds and functional groups, which have varied vibrational absorption and emission characteristics in different waveband ranges 40 .The presence and absence of strong molecular vibrations are necessary prerequisites for achieving high emission and high transmission in the corresponding wavebands, respectively.For the ideal adaptive-type textiles, the vibrational absorption and emission frequencies of their molecular bonds and functional groups should be restricted to the atmospheric window waveband (8-13 μm).Common functional groups of polymers and their wavelength ranges in the MIR region (4-25 μm) are listed in Fig. 2a.Based on the careful screening and analysis of these functional groups, POM, a widely used polymer with a backbone chain consisting only of C-O-C bonds, was hypothesized to combine both working modes of emission and transmission.This was experimentally confirmed by attenuated total reflection (ATR) mode Fourier transform infrared spectroscopy (FTIR; Fig. 2b) 41 .The characteristic peaks of the FTIR-ATR curve show that the wavelengths of the vibrational absorption and emission of POM are mainly distributed in the atmospheric window (Supplementary Table 3), indicating that POM is a promising raw material for developing radiative cooling textiles without reliance on the working environment.
In addition to selective MIR emission and transmission, strong solar reflectance is also necessary for radiative cooling materials for daytime outdoor environments.However, commercial POM products show low solar reflectance (~49.0%;Supplementary Fig. 10).According to the Mie scattering theory 8,33 , a fibre-based textile shows high scattering efficiency when its fibre diameter distribution is close to the waveband (Fig. 2a).Therefore, POM nanofibres with a diameter distribution comparable to sunlight wavelengths are hypothesized to show strong solar reflectance in daytime outdoor environments.Moreover, the fibre size is far from the MIR waveband, which results in a low Mie scattering efficiency in this band, and facilitates high human radiation transmittance in the non-window MIR waveband.
Based on the above analysis, a hierarchical POM nanofibre textile with a thickness of ~260 μm was synthesized through electrospinning (Fig. 2c, Supplementary Texts 6 and 7 and Supplementary Figs.11-14).The synthesized POM nanofibres were randomly stacked and showed a rough surface (Fig. 2d and Supplementary Fig. 15).This rough surface was formed due to the high volatility of the solvent A transmission-type textile with high solar reflectance is the best theoretical choice for this goal.However, the existing transmission-type textiles show poor cooling performance when exposed to outdoor heat due to the massive solar thermal load (from low solar reflectance) caused by the thickness limitation 5,14,33 .While various efforts, including the design of nanoparticle-and microparticle-based textiles, have been made to improve the solar reflectance of such materials 9,11,18 , it remains a challenge to balance human body compatibility (harmlessness and comfortability) and high cooling performance [34][35][36] .In addition, to realize good cooling performance for the emission-type textiles, there should be a clear heat transfer channel to send radiative heat to outer space through the atmospheric window.Therefore, when such materials are used in indoor environments and the channel for radiative heat transfer into outer space does not exist, the cooling performance is largely compromised 8,12 .In addition, even when outdoors, the atmospheric window may be partially or completely blocked during cloudy days, leading to substantially decreased cooling performance [37][38][39] .Therefore, to design a radiative cooling textile that supports high cooling performance in varied outdoor (including sunny and cloudy conditions) and indoor environments, it is crucial to precisely tune the optical properties of the material in multiple wavelength bands (including the atmospheric window, non-window of MIR and solar wavebands) to combine the advantages of both emission and transmission working modes.
Here we show a polyoxymethylene (POM) nanotextile design that embraces an adaptive heat dissipation mechanism between emission and transmission modes, enabling human body cooling independent of the environment (indoors and outdoors).Crucially, the POM textile shows a selective emittance of 75.7% in the 8-13 μm waveband (a high selectivity of 1.67, which is the ratio of the average emittance at 8-13 μm to that at 4-25 μm), a transmittance of 48.5% in the 4-25 μm waveband and a solar reflectance of 94.6% in the 0.3-2.5 μm waveband.As a result, the POM textile shows a notable enhanced radiative human body cooling performance, compared to typical transmission-type, emission-type and commercial cotton textiles in the sunny outdoor (7.8 °C, 2.6 °C and 8.8 °C cooler, respectively), cloudy outdoor (2.9 °C, 0.7 °C and 3.6 °C cooler, respectively) and indoor environments (−0.2 °C, 1.2 °C and 0.5 °C cooler, respectively).Furthermore, the POM textile also shows good breathability, high tensile strength and good performance in high-humidity conditions.Field tests show that our POM textile-based health-hazard-protective clothing showed notably better cooling performance than its commercial counterpart in sunny outdoor (5.4 °C cooler), cloudy outdoor (1.3 °C cooler) and indoor environments (~1.0 °C cooler).

Adaptive emission-transmission model
The mechanism behind our design for efficient human body cooling in different environments is shown in Fig. 1a.The MIR spectral characteristics are shown in Fig. 1b.The adaptive textile shows emission-type characteristics in the atmospheric window (8-13 μm) and transmission-type characteristics outside the window, rendering it with an optimal emissive cooling effect by fully exploiting the atmospheric window 24,33 while retaining the transmissive cooling capacity for most human body radiation (~61%, inset of Fig. 1b).Its semi-emissive and transparent characteristic overcomes the thickness limitation of transmission-type textiles and is expected to achieve high solar reflectance similar to emission-type textiles through nanostructured regulation.Due to the selective optical design, our textile design can achieve human body cooling through both MIR emission (mainly contributing to sunny outdoor cooling) and MIR transmission (contributing to both outdoor and indoor cooling), according to the mechanism shown in Fig. 1a.
The cooling performances of different types of textile (emission type, transmission type and adaptive type) in outdoor and indoor environments were evaluated and compared numerically by solving Article https://doi.org/10.1038/s41893-023-01200-x(hexafluoro-2-propanol) of POM solution in the electrospinning process 42,43 .The diameter size distribution of these POM nanofibres is close to the main solar waveband of 0.3-1.0μm (Fig. 2e) and away from the MIR waveband, which facilitates high solar reflectance and low MIR reflectance.In addition to the suitable nanofibre diameters, the disordered arrangement and rough surface of the POM nanofibres also contribute to the high solar reflectance of the POM textile (Supplementary Fig. 16) 33 .
Figure 2f shows that the synthesized POM textile shows a high solar reflectance of 94.6% in the waveband of 0.3-2.5 μm, and in the main solar waveband of 0.3-1.5 μm the average reflectance reached 95.2%.In comparison, in the MIR region of 4-25 μm, the POM textile showed an ultralow reflectance of 6.3% (inset of Fig. 2f), indicating that it has a high MIR emittance and transmission and thus is an ideal non-reflective textile.The POM textile shows a high selective emittance of 75.9% in the atmospheric window of 8-13 μm and an average transmittance of 70.0% outside the atmospheric window.Moreover, the average transmittance of the POM textile reaches 48.5% in the entire MIR region of 4-25 μm, indicating that it can transmit nearly half of the radiation energy from a human body.These results show that the synthesized POM textile has the properties of the above adaptive radiative cooling model and can be expected to provide environment-adaptive human body cooling.In the future, it is expected that POM films with similar optical properties can also be prepared by a low-cost solution method (Supplementary Text 8 and Supplementary Figs. 17 and 18), providing another convenient method for scale-up.

Thermal measurements
The all-weather radiative human body cooling performance of the synthesized POM textile was investigated with bespoke measurement devices (Fig. 3a,b) in three typical environments during hot summer days in Nanjing, China (118°57′10″ E, 32°07′14″ N), which included sunny outdoor, cloudy outdoor and indoor environments.Bare skin (uncovered skin simulator) and skin with three typical textiles (commercial cotton, emission-type polyvinylidene fluoride (PVDF) and transmission-type nanoporous PE (Nano-PE)) were studied for comparison (Supplementary Figs.19-24).As shown in Fig. 3c, the PVDF and Nano-PE textiles were carefully engineered and selected to match the emission-type and transmission-type radiative cooling models, respectively (see Supplementary Text 9 and Supplementary Figs. 20, 23 and 24 for details).Specifically, the selected PVDF and Nano-PE textiles achieved high emittance (90.0%) and transmittance (96.9%), respectively, in the entire MIR region, while the former also showed a high solar reflectance (95.1%) close to that of the POM textile, in agreement with the emission-type and transmission-type radiative cooling models, respectively.These samples were placed in similar measurement devices, with each device consisting of a textile sample, a skin simulator, surrounding insulating foam and a K-type thermocouple for monitoring the real-time temperature of the skin simulator (as shown in Fig. 3a,b).Constant input power (140 W m −2 ) was applied to the heaters to simulate the metabolic heat production rate of human skin, and the corresponding temperatures reflect the cooling performance of different samples.These skin simulators and thermocouples were carefully calibrated to ensure that the difference between measured temperatures was only caused by the different optical properties of the samples.
Figure 3d-g clearly show that in the outdoor environments (for both sunny and cloudy environments; Supplementary Fig. 25), the POM textile-covered skin simulator had the lowest surface temperature of the five samples.In the sunny scenario under strong direct sunlight (>800 W m −2 , with peak solar irradiance of ~935 W m −2 and a high ambient temperature T amb of 34.1 °C) from 10 a.m. to 1 p.m., the temperature of the POM textile-covered skin simulator was lower than that of the bare skin and the skin covered by cotton, Nano-PE and PVDF by 15.7 °C, https://doi.org/10.1038/s41893-023-01200-x8.8 °C, 7.8 °C and 2.6 °C, respectively (Fig. 3d,e and Supplementary Fig. 26).In a hot cloudy outdoor environment (T amb = 37.4 °C), the surface temperature of the POM textile-covered skin simulator was also much lower than the others, specifically by 5.5 °C, 3.6 °C, 2.9 °C and 0.7 °C, respectively (Fig. 3f,g and Supplementary Fig. 27).These results indicate that the POM textile shows the best outdoor cooling performance for a human body.This occurred due to its higher average solar reflectance than that of bare skin, cotton (~68%; Supplementary Fig. 28) and Nano-PE (~48.4%;Supplementary Fig. 19d), as well as its extra transmission cooling effect when compared with PVDF.The POM textile also showed good cooling performance in indoor environments, which allows a higher air temperature setpoint for active cooling devices to maintain human thermal comfort, which can save energy costs for cooling by ~7% per each 1 °C increase 8,44,45 .As shown in Fig. 3h,i, in a room at 30.4 °C, the temperature of the POM textile-covered skin simulator was lower than that covered with PVDF and commercial cotton by 1.2 °C and 0.5 °C, respectively, while it was only 0.2 °C higher than that covered with Nano-PE (Supplementary Fig. 29).Therefore, the human body cooling performance of the POM textile in an indoor scenario is close to that of the Nano-PE and better than that of both the PVDF and commercial cotton textiles.Our comprehensive consideration of the results in both indoor and outdoor thermal measurements clearly shows that the POM textile has the most effective cooling effect for the human body.Moreover, without a skin simulator (heater), the POM textile can also achieve good sub-ambient daytime cooling performance under strong sunlight owing to radiative sky cooling (Supplementary Figs. 30 and 31), indicating its application potential beyond personal thermal management.

Wearability of POM textile
In addition to the superior radiative cooling performance, the synthesized POM textile also shows many metrics required for wearability, namely, good breathability, mechanical strength, waterproofness and anti-humidity capability.First, we measured the POM textile's breathability, which refers to its ability to carry human body heat away from the textile by airflow under a pressure difference; this metric is important for human comfort.As shown in Supplementary Fig. 32, when sandwiching the POM textile between water and air, continuous bubble penetration (Supplementary Videos 1 and 2) without any textile breakage clearly indicates good breathability.As shown in Fig. 4a, quantitative air Article https://doi.org/10.1038/s41893-023-01200-xpermeability tests further showed that the POM textile shows similarly good breathability as commercial cotton, which occurs due to its fluffy fibrous structure and specially designed pores (that were punched by a commonly used microneedling technique 8 ; Supplementary Fig. 33).In addition, the water vapour transmission rate (WVTR) was also measured, which represents the ability of a textile to transfer water  vapour produced from perspiration evaporation.As shown in Fig. 4b and Supplementary Fig. 34, in the performance attributable to the existence of countless nanopore and micropore channels for water vapour permeation (Supplementary Figs. 15 and 35), the POM textile shows a high WVTR (0.011 g cm −2 h −1 ), which is similar to commercial cotton (0.010-0.012 g cm −2 h −1 ).
In addition, the POM textile also showed a high tensile strength of 13.3 MPa, which is comparable to that of commercial cotton (14.7 MPa) (Fig. 4c).The high mechanical strength is attributed to the high crystallinity of POM (Supplementary Fig. 36), which has a high inherent strength (70 MPa) 43 .The elongation of the POM textile is the highest (~300%) among these different textiles (Fig. 4c and Supplementary Fig. 37), indicating its high flexibility for comfortable interactions with skin.The anti-humidity capabilities, which are important for keeping a textile dry and clean in humid environments, of these samples were also compared.The water contact angle of the POM textile reached 138° and remained at 122° after half an hour, which was much higher than that of the other three textiles (Fig. 4d and Supplementary Fig. 38), indicating that the POM textile shows the highest waterproofness and anti-humidity capability.Moreover, the POM textile also showed high intense ultraviolet resistance (Supplementary Text 11 and Supplementary Fig. 39), high outdoor exposure stability (Supplementary Fig. 40), high abrasion resistance (Supplementary Fig. 41) and high colour compatibility (Supplementary Text 12 and Supplementary Figs.42-44) and can be modified to achieve good washability (Supplementary Text 13 and Supplementary Figs.45-47).
We also tested the real performance of the POM textile on a protective clothing by sewing a piece of POM cloth onto one side of the chest of a commercial protective clothing (where the commercial cloth at the corresponding position was previously cut and removed) while Sunny Cloudy Indoor

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https://doi.org/10.1038/s41893-023-01200-xretaining the other side for comparison (Fig. 4e,f and Supplementary Fig. 48).The thermal properties of a subject wearing the modified protective clothing were recorded in three typical environments (sunny outdoor, cloudy outdoor and indoor environments).The clothing surface temperature was captured and visually presented using an infrared camera (Testo, 8-14 μm).As shown in Fig. 4g, in the outdoor environments (both sunny and cloudy), the clothing temperature on the POM textile section was lower than that on the counterpart section during the continuous test.In the sunny outdoor scenario under strong direct sunlight (>800 W m −2 ), the surface temperature difference between the two parts of the clothing reached nearly 3.0 °C (Supplementary Video 3).In the cloudy outdoor environment with a solar irradiation of ~200 W m −2 , the temperature difference between the two parts of the clothing also reached 1.5 °C (Fig. 4g and Supplementary Video 4).
In addition, the corresponding skin temperatures under the clothing were also monitored in real time by bead-probe thermocouples (Fig. 4h-k).In a sunny outdoor environment (Fig. 4h,i), the skin temperature difference tested by thermocouples reached 5.4 °C, and the maximum difference even exceeded 6.0 °C (Fig. 4i).Clearly, the POM textile shows high potential in improving human thermal comfort under strong sunlight.The skin temperature difference was 1.3 °C in a cloudy outdoor environment (Fig. 4h,j).These results collectively show a notably enhanced radiative cooling performance of the POM textile over that of commercial protective clothing in various outdoor environments.Moreover, in the indoor environment, although the surface temperatures of the clothing on both parts were similar to each other (Fig. 4g and Supplementary Video 5), the skin temperature under the POM cloth was nearly 1.0 °C lower than that under the commercial counterpart (Fig. 4h,k).Thus, the POM textile also showed better indoor cooling performance.Therefore, the POM textile showed superior cooling performance over that of commercial protective clothing in both outdoor and indoor environments and should have high commercialization potential.The same conclusion can be drawn from the thermal measurement of another protective clothing based on a larger POM textile (~20 × 40 cm 2 ) in similar environments (Supplementary Fig. 49 and Supplementary Videos 6-8).

Discussion
We designed a hybrid radiative cooling model for environment-adaptive radiative human body cooling and fabricated a POM textile that showed a selective emittance of 75.7% in the atmospheric window (8-13 μm), a high human radiation transmittance of 48.5% (4-25 μm) and a high solar reflectance of 94.6% (0.3-2.5 μm).The POM textile showed superior human body cooling performance when compared with existing typical radiative cooling textiles and a commercial cotton textile in both outdoor and indoor environments (0.5-8.8 °C cooler).The POM textile also shows good wearability, such as high breathability, good tensile strength and high anti-humidity capability.A POM textile-based protective clothing demonstrated superior practical cooling effect (nearly 1-6 °C cooler) over a commercial counterpart in both outdoor and indoor environments.This work provides a solution to the incompatible designs for outdoor and indoor human body cooling, contributing to the next generation of sustainable personal thermal management.

Fabrication of POM and PVDF textiles
Some 5 wt% POM solution was prepared by adding POM powder (commercial grade, Aladdin) into 1,1,1,3,3,3-hexafluoro-2-propanol (99%, Aladdin) while stirring.The mixture was continuously stirred at 40 °C for 2 h.The resulting homogeneous solution was electrospun using a 20-gauge needle tip with a voltage of 18 kV and a feed rate of 2 ml h −1 .The spinning distance, relative humidity and temperature during spinning were 18 cm, 40% and 25 °C, respectively.The PVDF textile was obtained using the same method.Some 13 wt% PVDF (Mv ~370000, Kynar) solution in a dimethylformamide (99%, Aladdin) and acetone (AR, Tongguang) mixed solvent (4:1, v/v) was prepared.The mixture was continuously stirred at 50 °C for 5 h.The resulting solution was electrospun using a 19-gauge needle tip with a voltage of 12 kV, a feed rate of 0.5 ml h −1 and a spinning distance of 20 cm.The relative humidity and temperature were ~40% and 32 °C, respectively.Nano-PE (~15 μm, Asahi-KASEI) and commercial cotton (~300 μm) were obtained commercially.

Spectral characterization
The spectral properties of the POM textile were characterized separately in the solar spectrum (0.3-2.5 μm) and MIR (2.5-25 μm) wavebands.In the first range, the solar reflection and transmission spectra were recorded using an ultraviolet-visible-near-infrared spectrophotometer (Cary 7000, Agilent) equipped with an integrating sphere model (Internal DRA-2500, Agilent) that used barium sulfate as the baseline material.For the second range, a FTIR spectrometer (INVENIO, Bruker) equipped with a gold integrating sphere (A562, Bruker) was used to measure the absorption-emission and transmission spectra (gold was used as the baseline material).

Morphology characterization
Optical images of the samples were taken by a digital camera (Nikon DSLR D5100).The microstructure of the POM textile was characterized by a scanning electron microscope ( JSM7900F).

Thermal measurements
The cooling effects of the different textiles were measured using the devices shown in Fig. 3a (schematic) and Fig. 3b (photograph).Human skin was simulated by a layered structure of Kapton heater, thermally conductive silicone grease, Cu plate and paint.The Kapton heater was connected to a direct current power source that provided ~140 W m −2 heating power, which is the heat flux from a body's metabolic heat generation.The thermally conductive silicone grease and Cu plate with a thickness of 5 mm served as thermal connection and heat diffuser, respectively, for a uniform temperature distribution.The paint was blended to have a skin-like spectrum in both the solar waveband and MIR wavebands.Aluminium foil and foam in the test device were utilized to minimize the thermal impact from the surroundings, as in a method used in previous works.K-type thermocouples connected to a recorder (MIK-R6000C, Asmik) were used to monitor the sample's temperature in real time.The thermocouples were carefully calibrated with a test error of 0.4 °C for the outdoor tests and 0.1 °C for the indoor measurements.The ambient conditions (including input sunlight power, ambient temperature and relative humidity) during the outdoor tests were measured and recorded by a weather station (TS-G1, Tuolaisi) adjacent to the test devices.

Wearability tests
In the WVTR test, the WVTRs of the POM textile, emission-type PVDF, transmission-type PE, commercial cotton and normal PE sealing film were measured by the methods previously reported.Bottles (50 ml) filled with distilled water were sealed by the textile sample with rubber bands.These sealed bottles were kept in an environment with constant temperature (30 °C) and relative humidity (40%).The weight of the sealed bottles was recorded every 6 h for 72 h.The WVTRs were obtained by dividing the reduction in mass due to water evaporation by the exposed area of the textile.

Air permeability tests
The POM textile was sealed between two pipes that were open above and sealed below.The exposed area of the textile was ~20 cm 2 .The bottom pipe was connected to a compressed air source and the top pipe was filled with water and open to air.The gas permeability of the sample was qualitatively assessed by observing the air bubbles and membrane integrity after a constant flow rate of gas (20 standard cubic centimeters per minute) was introduced.The quantitative testing Article https://doi.org/10.1038/s41893-023-01200-xprocedure was based on GB/T 24218.15-2018(Chinese standard; GB/T stands for recommended national standard).The textile sample was sealed between two pipes.The exposed area of textile was 20 cm 2 .One pipe was connected to a compressed air source, and the other one was exposed to open air.A differential pressure gauge was connected to the two pipes to measure the pressure drop across the textile sample at different air flow rates.The air permeability of electrospun films decreases with increasing thickness, which made our POM textile slightly less breathable than commercial cotton (Supplementary Fig. 32a).To represent the breathability of the POM textile in commercial applications, the above POM textile was punched with ~100 μm holes every 1 mm (invisible to the naked eye; Supplementary Fig. 32b,c) using the microneedling technique commonly used in the textile industry.

Mechanical test
The tensile strength tests of the POM textile, emissive-type PVDF, transmissive-type PE and commercial cotton were measured by a Servo tensile testing machine (HZ-1004A).The samples had the same size (2 cm wide, 10 cm long) and a gauge distance 6 cm long.The displacement rate was 10 mm min −1 .

Anti-humidity test (contact angle versus time)
The water contact angle of the textile sample was measured using a contact angle analyser (XG-CAMA1) at a room temperature of ~25 °C and an ambient relative humidity of ~40%.The contact angle for each sample was recorded continuously for half an hour.

Washing test
The washing test was undertaken using a household mini washing machine (Nanjiren, XP10) according to ISO 6330 standard with domestic washing and drying.The POM textile and anti-bacterial detergent (ARIEL, Procter & Gamble) were added to the washing machine to form a 2.3 kg load, followed by a standard washing and drying cycle (40 °C, 50 min).Spectral characterization was performed after every 10 washing cycles.

Ultraviolet exposure test
The ultraviolet exposure test was conducted by exposing the POM textile to intense ultraviolet irradiation (125 W m −2 , 60 °C).Spectral characterization was performed after every 20 h of continuous ultraviolet exposure.

Outdoor exposure test
The outdoor exposure test was conducted by continuously exposing the POM textile on an outdoor open roof (Beijing, China) with direct sky exposure for 2 months (60 days, 16 September 2022 to 15 November 2022).

Friction test
The friction test was conducted using a Martindale Abrasion and Pilling Tester (658Q0018, SDL Atlas) according to ISO 12947 standard.First, the sample was placed in the test room with a constant environment (temperature 25 °C, humidity 45%) for 24 h.Then the sample was cut into circular discs of the same size (diameter, 3.5 cm) that were fixed on the apparatus for different cycles of friction.The abrasion resistance of the POM textile was evaluated by textile appearance, mass loss rate and spectral characteristics before and after the friction test.

Protective clothing test
A commercial medical protective clothing (50% polypropylene non-woven fabric + 50% PE) was used.The modified protective clothing was obtained by sewing a piece of POM cloth (~20 × 20 cm 2 ) onto one side of the chest of the commercial protective clothing after removing the commercial cloth there (Supplementary Fig. 48).The commercial cloth on the other side was retained for comparison.The surface temperatures of the clothing and human body were monitored using an infrared camera (Testo 890, 8-14 μm) and K-type thermocouples, respectively.The solar irradiation was recorded with a solar power meter (TES-1333, TES).The tests were performed in sunny outdoor, cloudy outdoor and indoor environments in Beijing, China (May 2022, 40°0′33″ N, 116°20′0.6″E).To further verify the effectiveness of the POM textile as protective clothing, another protective clothing based on a larger size POM textile (~20 × 40 cm 2 ; Supplementary Fig. 49) was made and tested in similar sunny (outdoor), cloudy (outdoor) and indoor environments in Beijing, China.

Statistics
For all statistical analyses, confirm that the following items are present in the figure legend, table legend, main text, or Methods section.

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A description of all covariates tested
A description of any assumptions or corrections, such as tests of normality and adjustment for multiple comparisons A full description of the statistical parameters including central tendency (e.g.means) or other basic estimates (e.g.regression coefficient) AND variation (e.g. standard deviation) or associated estimates of uncertainty (e.g.confidence intervals) For null hypothesis testing, the test statistic (e.g.F, t, r) with confidence intervals, effect sizes, degrees of freedom and P value noted Give P values as exact values whenever suitable.
For Bayesian analysis, information on the choice of priors and Markov chain Monte Carlo settings For hierarchical and complex designs, identification of the appropriate level for tests and full reporting of outcomes Estimates of effect sizes (e.g.Cohen's d, Pearson's r), indicating how they were calculated Our web collection on statistics for biologists contains articles on many of the points above.

Software and code
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Data analysis
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Fig. 1 |
Fig. 1 | Design and model calculations of a textile taking an adaptive radiative cooling mode.a, Schematic of the textile design that features adaptive human body radiative cooling.b, Spectral features in the MIR region of the adaptive emission-transmission radiative cooling model.Inset: selective emission (39%) and partial transparency (transmission, 61%) to human body radiation of the adaptive-type radiative cooling textile.c, Simulated skin surface temperature as a function of MIR emissivity of the textile at constant ambient temperature and human metabolic generation rate (140 W m −2 ).d,e, Comparison of the calculated skin surface temperature of the three radiative cooling models in sunny outdoors (d) and indoors (e).

Fig. 2 |
Fig. 2 | Design, preparation and spectral analysis of the POM textile.a, Nanostructure regulation of adaptive-type textiles in the solar irradiation region (left) and the POM functional group selection in the MIR region (right).AM1.5 solar spectum is the standard solar spectra at air mass 1.5.b, FTIR-ATR spectrum of POM.The main absorption-emission characteristic peaks of the C-O-C vibrational bonding are in the atmospheric window, and the other region is dominated by transmission.Inset: schematic of the POM molecular chain.The red and blue boxes indicate the atmospheric window and non-window

Fig. 3 |
Fig. 3 | Human body cooling measurements of the POM textile, by comparing it with bare skin and skin covered by commercial cotton, transmission-type PE and emission-type PVDF.a, Schematic of the thermal measurement device to characterize radiative human body cooling both outdoors and indoors.b, Photograph of the devices.Scale bar, 30 cm. c, Comparison of solar reflectance (0.3-2.5 μm), MIR emittance (4-20 μm) and MIR transmittance (4-20 μm) between POM, transmission-type PE and emission-type PVDF textiles.The MIR emittance Article https://doi.org/10.1038/s41893-023-01200-x

Fig. 4 |
Fig. 4 | Wearability testing of the POM textile.a-d, Comparison of the wearability of POM, commercial cotton, emission-type PVDF and transmissiontype PE textiles (denoted as POM, Cotton, Emissive PVDF and Transmissive PE, respectively), including an air permeability test (a), WVTR versus time (b), mechanical strength test (c) and water contact angle versus time (d).e,f, Schematic (e) and photograph (f) of a person wearing the POM-textile-based protective clothing.The yellow (left) and blue (right) boxes in e indicate the indoor and outdoor environments, respectively.Scale bar, 20 cm.g, Infrared images of the person wearing the protective clothing in sunny outdoor (16 May Corresponding author(s): Jia Zhu; Rufan Zhang Last updated by author(s):Jun 11, 2023   Reporting Summary Nature Portfolio wishes to improve the reproducibility of the work that we publish.This form provides structure for consistency and transparency in reporting.For further information on Nature Portfolio policies, see our Editorial Policies and the Editorial Policy Checklist.
Cloudy day (25 May 2022) with a ambient temperature of ~37 °C, a relative humidity of 25%-40%, a wind speed of ~0.5 m s-1, and a solar radiation of 200-300 W m-2; Location Nanjing, Jiangsu province, ChinaAccess & import/export There are no local limitations for accessing the aforementioned locations & importing/exporting our samplesDisturbanceThe extra thermal radiation from surrounding buildings can affect the test results and to avoid this effect, an open and unobstructed test site is requiredReporting for specific materials, systems and methodsWe require information from authors about some types of materials, experimental systems and methods used in many studies.Here, indicate whether each material, system or method listed is relevant to your study.If you are not sure if a list item applies to your research, read the appropriate section before selecting a response.