Applications of two-dimensional layered nanomaterials in photoelectrochemical sensors: A comprehensive review

As an emerging innovative detection technique, photoelectrochemical (PEC) assay has played an important role in the advancement of analytical methods. Up to now, PEC technique has received more attentions owing to the advantages of low background signal, easy operation, inexpensive instrument and high sensitivity. In the construction of PEC sensing platform, an appropriate photoelectrode is essential, where semiconductors are very attractive due to their excellent photoactivity. Among various semiconductors, two-dimensional (2D) layered nanomaterials are of great interest because of the merits of high specific surface area, fast electron transfer rate, good light harvest property, easy preparation and exfoliation, and good biocompatibility. Currently, the impetus for the application of 2D layered nanomaterials in PEC sensing and biosensing has grown rapidly. In this work, the advance of the application of 2D layered nanomaterials in PEC assay field was reviewed, where 2D layered nanomaterials includes graphene and its derivatives, graphite carbon nitride, transition metal dichalcogenides (MoS2, MoSe2, WS2, and WSe2), bismuth oxyhalides (BiOCl, BiOBr and BiOI), hexagonal boron nitride, borocarbonitrides, MXene (Ti3C2 and Ti3C2Tx), Bi2Te3, metal–organic frameworks, covalent organic frameworks, phosphorene, graphdiyne, layered double hydroxides, Xenes and perovskite. The detection performances of these PEC sensor and biosensor based on 2D layered nanomaterials were compared for various targets. The future prospects were also discussed.