High-Yield Delamination of Hydrothermally-Etched V2CTx

Abstract

The delamination of hydrothermally etched V₂CT_x has presented challenges, with limited reports of an effective delamination process. X-ray diffraction data indicate that excess lithium and lithium salts in the reaction mixture interact with the multilayered MXene surfaces in the interlayer space, impeding intercalants that would separate the nanosheets. The removal of this salt with a dilute acid solution is the key step to enable the synthesis of a delaminated MXene with a markedly higher yield in comparison to that of traditional HF-etched (and delaminated) V₂CT_x. Because this yield is substantial, the sample can be centrifuged to produce 20 mL of a concentrated (25 mg mL^–1) sample. Due to the removal of excess water and dissolved O₂, this concentrated sample shows improved stability toward oxidation and can withstand ambient conditions over the course of a year.