Flexibility and power supply needless are two demands of the emerging electronics, including sensor, processer and so on. Wearable infrared sensor is an important part of intelligent and medical sensing. In this work, a self-powered flexible infrared sensor with photo-thermo-electric energy conversion is designed based on the composite film of polyvinyl alcohol (PVA)/poly-(3,4-ethylene dioxythiophene): polystyrene sulfonate (PEDOT: PSS)/Ti₃C₂T_x. Appropriate content of Ti₃C₂T_x nanoflakes improves the Seebeck coefficient and greatly enhances light absorption simultaneously. Bionic micro-dome structure is employed to the surface of the film to further enhance the light absorption for better photo-thermal conversion. As results, the composite film with 5 mg Ti₃C₂T_x shows a Seebeck coefficient up to 37.57 μV K⁻¹, a response time <0.75 s and great stretchability (up to 200 %). At 2 mW cm⁻² power density of an 850 nm laser, the film generates 220 μV thermal voltage, which is 44 times of that of the film without Ti₃C₂T_x. An infrared sensor array based on this composite film is designed for the successful imaging of a human palm. This self-powered infrared sensor shows great application prospects in the fields of wearable non-visual perception and intelligent sensing.