Two novel two-dimensional (2D) supramolecular organic frameworks were fabricated in water based on the encapsulation-enhanced donor-acceptor interaction between the methyl viologen (MV) units, methoxy naphthyl (MN) units, and CB [8]. The tetraphenylethylene (TPE) derivatives 1 with four MV units were employed as rigid building blocks and the two MN units modified oligoethylene glycol derivatives 2 and 3 served as flexible edges, respectively. The obtained two SOFs have obvious sheet-like structures and exhibit fluorescence emission at 350–500 ​nm. In addition, these two SOFs were employed for the luminescent detection of Cr(Ⅵ) and Mn(Ⅶ) in aqueous solutions, and the detection limits of CrO₄²⁻, Cr₂O₇²⁻, and MnO₄⁻ were calculated in a very low concentration range, indicating that these two SOFs can serve as a potential sensor for Cr(Ⅵ) and Mn(Ⅶ) detection in water. This work constructs two SOFs in an aqueous solution through a facile method and further enriches the applications of SOFs.

MXenes are emerging transition metal carbides and nitrides-based 2D conductive materials. They have found wide applications in sensors due to their excellent valuable properties. This paper reviews the recent research status of MXene-based electrochemical (bio) sensors for detecting biomarkers, pesticides, and other aspects. The first part of this paper introduced the synthesis strategy and the effect of surface modification on various properties of MXenes. The second part of this paper discussed the application of MXenes as electrode modifiers for detecting pesticides, environmental pollutants, and biomarkers such as glucose, hydrogen peroxide, etc. Hope this review will inspire more efforts toward research on MXene-based sensors to meet the growing requirements.