Optical fiber tip integrated photoelectrochemical sensors

In this work, we design and fabricate a compact photoelectrochemical (PEC) sensor by integrating a graphene-MoS2 heterostructure on an optical fiber tip. The graphene serves as a transparent carrier transport layer, and the MoS2 presents a photoelectrical transducer that generates photocarriers and interacts with ascorbic acid (AA) in solution. This device is used to demonstrate a self-powered detection of AA with a concentration range between 1 mM and 50 mM, and a time response of similar to 6 ms. The device downsizes traditional PEC systems to the micrometer scale, benefiting the real-time monitoring of biochemical changes in small areas and opening the pathway for miniaturized PEC sensing applications. (C) 2022 Optica Publishing Group under the terms of the Optica Open Access Publishing Agreement