• • The Sb2S3/HgS heterojunction photodetector achieves a detectivity of 1.7 × 10^11 Jones and an ultrafast response time of 2.47 ms, enabling high-sensitivity, high-speed optical signal acquisition for real-time healthcare monitoring.
• • The device operates self-powered across a broadband spectral range of 642–1550 nm, covering both visible and near-infrared biological transparency windows, which is critical for non-invasive diagnostics such as photoplethysmography.
• • The photodetector maintains nearly constant photocurrent over 5000 continuous on-off switching cycles and prolonged air exposure, demonstrating operational stability essential for long-term wearable or implantable medical devices.
• • The bioinspired bidirectional bonding strategy (Sb–O and Sb–S/Hg–S bonds) simultaneously enhances interfacial adhesion and passivates defects, providing a generalizable route to stabilize solution-processed chalcogenide optoelectronics for scalable manufacturing.