Metal‐Based Flexible Optoelectronic Materials: From Structural Foundation to Biomedical Sensor Application

Abstract Metal‐based flexible optoelectronic materials have demonstrated considerable potential in the construction of high‐performance biosensing platforms, a feat attributable to their unique combination of mechanical flexibility and exceptional electrical properties. In recent years, significant advancements have been made in enhancing electrical conductivity, signal enhancement capability, and material stability through structural modulation and metallization modification of flexible substrates. These developments have effectively promoted the development of flexible sensors toward real‐time, wearable, and noninvasive applications. Here, a systematic overview of the key properties of common flexible substrate materials is provided and focus is on how the current mainstream metallization strategies, including vapor deposition, chemical reduction deposition, and in situ reduction growth pathways, modulate the metal layer structure to enhance the sensing performance. A thorough examination of the conventional applications of these materials in mechanical, optical, and electrochemical sensing of biological signals is conducted. Finally, the remaining challenges and the perspective of metal‐based flexible optoelectronic materials are discussed.