1：Experimental Design and Method Selection:

The study involves designing a trilayer Janus membrane using hydrothermal synthesis and vacuum filtration methods to achieve asymmetric radiation properties. The rationale is to combine materials with high solar reflectivity/high infrared emissivity (ZnO-NRs@cellulose) and high solar absorptivity/low infrared emissivity (Ag-NWs) for thermal management.

2：Sample Selection and Data Sources:

Materials include zinc nitrate hexahydrate, zinc acetate dihydrate, isopropyl alcohol, triethylamine, anhydrous ethanol, hexamethylenetetramine, potassium sulfate, nitric acid, potassium persulfate, manganese sulfate monohydrate, silver nitrate, polyvinylpyrrolidone, ethylene glycol, and qualitative filter paper. All reagents were purchased from Sinopharm Chemical Reagent Co., Ltd., and deionized water was used.

3：List of Experimental Equipment and Materials:

Equipment includes a Teflon-lined stainless steel autoclave, vacuum-filtration setup, field emission scanning electron microscopy (SEM, JEOL JSM-6010), transmission electron microscopy (TEM, JEM-2010), X-ray diffractometer (XRD, Shimadzu XRD-6100), tensile testing equipment (SHIMAZDU AGS-J), infrared camera (FLIR ONE Gen 3), UV–vis–NIR spectrophotometer (Agilent Cary 6000i), and Thermo ESCALAB 250XI instrument. Materials are as listed in section 2.

4：Experimental Procedures and Operational Workflow:

1. 4. Experimental Procedures and Operational Workflow: Preparation of Ag nanowires via one-pot synthesis in autoclave at 130°C for 8h. Preparation of Janus membrane by vacuum filtrating UL-MnO2-NWs and Ag-NWs sequentially onto ZnO-NRs@cellulose fiber membrane at 0.05 MPa, followed by incubation at 60°C under pressure. Characterization involves SEM, TEM, XRD, mechanical testing, thermal imaging, UV–vis–NIR spectra, and infrared emissivity measurements. Radiation property evaluation using a model house and solar simulator.

5：8h. Preparation of Janus membrane by vacuum filtrating UL-MnO2-NWs and Ag-NWs sequentially onto ZnO-NRs@cellulose fiber membrane at 05 MPa, followed by incubation at 60°C under pressure. Characterization involves SEM, TEM, XRD, mechanical testing, thermal imaging, UV–vis–NIR spectra, and infrared emissivity measurements. Radiation property evaluation using a model house and solar simulator. Data Analysis Methods:

5. Data Analysis Methods: Data analysis includes morphological observation, phase structure identification, mechanical strength testing, spectral analysis, and temperature measurements using specified instruments and software.