Facile, Real‐Time Identification of Blood Components with Self‐Powered Organic–Inorganic Heterostructure Photodetectors

Abstract A rapid and efficient opto‐electrical method for the determination of blood components is demonstrated through a tin oxide (SnO₂) quantum dot (QD) fluorene copolymer heterojunction photodetector (FP‐PD). The photo‐active materials, the device structure, and the sensing system are carefully designed to provide miniaturization at a low cost. SnO₂ QDs are synthesized with a one‐step solvothermal reaction and a photodetector, and then fabricated in a simple sequential spin‐coating process. Under optimal conditions, the SnO₂ QD/FP‐PD shows remarkable responsivity, detectability, fast responses, and stability under self‐powered operation. In this research, optical characteristics of blood components, and interactions between the photodetector and blood components from illuminating two different wavelengths of ultraviolet light, are systemically investigated. Furthermore, three different blood component mixtures are successfully determined by the SnO₂ QD/FP‐PD based on specific absorption phenomena, which provides a simple and efficient technique for emergency medical care and health monitoring systems.