Yuqi Sun

Metal halide perovskite semiconductors have demonstrated remarkable potentials in solution-processed blue light-emitting diodes (LEDs). However, the unsatisfied efficiency and spectral stability responsible for trap-mediated non-radiative losses and halide phase segregation remain the primary unsolved challenges for blue perovskite LEDs. In this study, it is reported that a fluorene-based π-conjugated cationic polymer can be blended with the perovskite semiconductor to control film formation and optoelectronic properties. As a result, sky-blue and true-blue perovskite LEDs with Commission Internationale de l'Eclairage coordinates of (0.08, 0.22) and (0.12, 0.13) at the record external quantum efficiencies of 11.2% and 8.0% were achieved. In addition, the mixed halide perovskites with the conjugated cationic polymer exhibit excellent spectral stability under external bias. This result illustrates that π-conjugated cationic polymers have a great potential to realize efficient blue mixed-halide perovskite LEDs with stable electroluminescence.

Flexible photodetectors (PDs) prepared with silicon-based materials have received considerable attention for their use in a wide range of portable and wearable applications. In this study, we present the first free-standing flexible PD based on sulfur-hyperdoped ultrathin silicon, which was fabricated using a femtosecond laser in a SF6 atmosphere. It is found that the fabricated device exhibits excellent performance of broadband photoresponse from 400 to 1200 nm, with a peak responsivity of 63.79 A/W @ 870 nm at a low bias voltage of −2 V, corresponding to an external quantum efficiency reaching 9092%, which surpasses most values reported for silicon-based flexible PDs. In addition, the device shows a fast response speed (rise time τr = 68 μs) and stable detection performance with good mechanical flexibility. The high-performance PD described here suggests a promising way in flexible applications for sensors, imaging systems, and optical communication systems.

Effective bio-recognition element immobilization on the surface of the transducer is significantly important for fabricating an immunosensor. Pithophora. Oedogonia, a green algae, has been employed as the reducing agent in this study to accomplish the biosynthesis of Au nanoparticles. The whole procedure of synthesis occurred rapidly where Au nanoparticles were produced within 1 h after the reaction between Au salt and algal extract. Subsequently, electrochemical impedance myoglobin immunosensor was constructed using the obtained AuNPs. A wide detection range can be achieved from 0.02 to 1μM either in phosphate buffered saline or the whole serum, Furthermore, the as-fabricated immunosensors is potential to be utilised for the detection of myoglobin.