Shenzhen Advanced Institute developed the first black phosphorus fiber chemical sensor for ultra-sensitive detection of heavy metal ions

Recently, Lv Jiancheng and Yu Xuefeng, researchers of the Shenzhen Institute of Advanced Technology of the Chinese Academy of Sciences, and Chen Xianfeng, a professor at the University of Bangor in the United Kingdom, have successfully developed the first black phosphorus-based optical fiber chemical sensor to achieve ultra-sensitive detection of heavy metal ions.

The research team combined the black phosphorus and the tilted fiber grating to reveal the unique optical modulation of the black phosphorus nano-layer. With the unique optical structure of the tilted grating, a new ultra-sensitive chemical sensor was constructed. In this study, an in-situ lamination modification technique was developed to efficiently attach black phosphorus nanosheets to the surface of fiber optic devices. Different thicknesses of black phosphorus nanolayers exhibited unique modulation of optical signals. Through this feature, the black phosphorus fiber sensor can detect heavy metal lead ions at the sub-ppb concentration level, with ultra-high sensitivity, ultra-low detection limit, and a wide concentration detection range. The successful development of the new black phosphorus fiber sensor will provide a superior optical detection platform for chemical and biological sensing, thus promoting the application research process of black phosphorus chemical biosensor.

Figure a): Black phosphorus tilted fiber grating device and its optical modulation diagram, b): experimental steps for heavy metal ion detection,

c): Spectral diagram of TM mode resonance at different heavy metal ion concentrations, d): Resonance intensity of the spectrum at different heavy metal ion concentrations

Currently, relevant research results have been published in Sensors and Actuators B: Chemical. The research was funded by the National Natural Science Foundation of China and the EU's Seventh Framework Programme.