Herein, facile room-temperature self-assembly and high-temperature pyrolysis strategy was successively conducted for in situ synthesizing novel TiO2/ TiN@N-C heterostructure by using typical sandwich-like precursors (MXene/ZIF-8). Zerodimensional (0D) TiO2, TiN and N-doped carbon nanoparticles were in situ formed and randomly anchored on the twodimensional (2D) N-doped carbon substrate surface, making TiO2/ TiN@N-C exhibit unique 0D/2D heterostructure. Relative to the extensively studied ZIF-8-derived N-doped carbon nanoparticles, TiO2/ TiN@N-C heterostructure displayed greatly boosted electrochemical active specific surface. Benefiting from the enhanced electrochemical property of TiO2/ TiN@N-C heterostructure, remarkable signal enhancement effect was achieved in terms of the oxidation of multiple hazardous substances, including clozapine, sunset yellow and benomyl. As a result, a novel electrochemical platform was constructed, the linear detection range were 10–1000 nM, 2.5–1250 nM, 10–1000 nM while the detection limits were evaluated to be 3.5 nM, 1.2 nM, 4.5 nM for clozapine, sunset yellow and benomyl, respectively. Besides, the practicability of the newly developed electrochemical method was verified by assessing the content of clozapine, sunset yellow and benomyl in real food samples.

Interest in eco-friendly materials with high efficiencies is increasing significantly as science and technology undergo a paradigm shift toward environment-friendly and sustainable development. MXenes, a class of two-dimensional inorganic compounds, are generally defined as transition metal carbides or nitrides composed of few-atoms-thick layers with functional groups. Recently MXenes, because of their desirable electrical, thermal, and mechanical properties that emerge from conductive layered structures with tunable surface terminations, have garnered significant attention as promising candidates for energy storage applications (e.g., supercapacitors and electrode materials for Li-ion batteries), water purification, and gas sensors. In this review, we introduce MXenes and describe their properties and research trends by classifying them into two main categories: transition metal carbides and nitrides, including Ti-based MXenes, Mo-based MXenes, and Nb-based MXenes.