biostudies-literatureWu JBionic structured materials technology joint laboratory for advanced mateirals between China and Portugalthe National Key Research & Development Program of Chinathe National Natural Science Foundation of China5008https://www.ebi.ac.uk/biostudies/studies/S-EPMC11547708biostudies-literatureUnknown29(21)Photothermal materials often prioritize solar absorption while neglecting thermal radiation losses, which diminishes thermal radiation conversion efficiency. This study addresses this gap by introducing a germanium (Ge) subwavelength structure (SWS) designed to optimize both solar absorption and infrared emissivity. Using a self-masked reactive ion etching (RIE) technique, we achieved a peak absorption of 98.8% within the 300 nm to 1800 nm range, with an infrared emissivity as low as 0.32. Under solar illumination of 1000 W/m², the structure's temperature increased by 50 °C, generating a heating power of 800 W/m². Additionally, it demonstrated good mechanical and thermal stability at high temperatures and possessed a hydrophobic angle of 132°, ensuring effective self-Molecules (Basel, Switzerland)Ideal Photothermal Materials Based on Ge Subwavelength Structure.PMC1154770862375132, 62305164, 5247020620SQ2024YFE01011452022YFA160300Wu JWei CMa JXu HZheng WZhu RWang KfalseIdeal Photothermal Materials Based on Ge Subwavelength Structure.Photothermal materials often prioritize solar absorption while neglecting thermal radiation losses, which diminishes thermal radiation conversion efficiency. This study addresses this gap by introducing a germanium (Ge) subwavelength structure (SWS) designed to optimize both solar absorption and infrared emissivity. Using a self-masked reactive ion etching (RIE) technique, we achieved a peak absorption of 98.8% within the 300 nm to 1800 nm range, with an infrared emissivity as low as 0.32. Under solar illumination of 1000 W/m², the structure's temperature increased by 50 °C, generating a heating power of 800 W/m². Additionally, it demonstrated good mechanical and thermal stability at high temperatures and possessed a hydrophobic angle of 132°, ensuring effective self-2024-01-01T00:00:00Z2024 Oct2025-04-04T00:38:46.279Z2025-04-04T00:38:46.279ZS-EPMC115477083951964910.3390/molecules29215008