A ratiometric fluorescent probe based on water-soluble CsPbX (Br/I) perovskite nanocrystals for sensitive detection of tetracycline.

A dual supersaturation recrystallization method was employed to synthesize water-stable, highly sensitive cesium-lead halide perovskite nanocrystals (CsPbBr PNCs). The PNCs exhibited excellent water stability, a significant photoluminescence quantum efficiency of 83.03%, along with a narrow full width at half maximum (FWHM) of 20 nm.

A room-temperature ultrasonic hydrogen sensor based on a sensitive layer of reduced graphene oxide.

It is challenging to increase the sensitivity of a hydrogen sensor operating at room temperature due to weak sorption and tiny mass of hydrogen. In this work, an ultrasonic sensor is presented for detecting hydrogen, which is composed of a 128° YX-LiNbO substrate and a reduced graphene oxide (RGO) sensitive layer with a platinum catalyzer. By optimizing the depositing parameters of RGO and platinum, a considerably high sensitivity is achieved at room temperature.