Iron phosphorus trichalcogenide ultrathin nanosheets: enhanced photoelectrochemical activity under visible-light irradiation

Exploiting novel visible-light sensitive materials for the photoelectrochemical (PEC) technique is deeply meaningful for energy conversion and analytic detection. Owing to the tunable bandgap structure and strong absorption of visible light, the rising-star two-dimensional (2D) metal phosphorus trichalcogenide (MPX₃) nanomaterials are expected to be promising photochemical sensitizers toward PEC biosensors. Moreover, guided by DFT calculations, the FePS₃ nanosheets possessed a narrower bandgap than the bulk form, thereby enabling high availability of visible-light absorption for the FePS₃ nanosheets. In this work, 2D FePS₃ nanosheets were successfully synthesized by a facile salt-templated method. By tuning the proportion of the salt template, the thickness of the FePS₃ nanosheets could be manipulated. As a result, the FePS₃ nanosheets exhibited an obviously enhanced photoelectrochemical behavior with visible light and sensitive detection towards glucose. Being the first experimental report regarding the MPS₃ nanosheets toward PEC activity, our finding can be an essential stepping stone in the pursuit of the further exploration of other 2D materials for the PEC technology.