Electrochemical etching of Ti 2 AlC to Ti 2 CT x (MXene) in low-concentration hydrochloric acid solution Academic Article uri icon

abstract

  • © 2017 The Royal Society of Chemistry. In this study, we successfully demonstrate the electrochemical etching of Al from porous Ti2AlC electrodes in dilute hydrochloric acid to form a layer of Ti2CTx MXene on Ti2AlC. This is the first report on etching of the A layer from the MAX phase in a fluoride-free solution as a less hazardous method to process and handle MXenes. In addition, these MXenes possess only -Cl terminal groups, as well as the common ones, such as -O and -OH. However, electrochemical etching can also result in subsequent over-etching of parent MAX phases to carbide-derived carbon (CDC). We propose a core-shell model to explain electrochemical etching of Ti2AlC to Ti2CTx and CDC. The proposed model suggests that a careful balance in etching parameters is needed to produce MXenes while avoiding over-etching. Our electrochemical approach expands the possible range of both etching techniques and resulting MXene compositions.

altmetric score

  • 4.6

author list (cited authors)

  • Sun, W., Shah, S. A., Chen, Y., Tan, Z., Gao, H., Habib, T., Radovic, M., & Green, M. J.

citation count

  • 73

publication date

  • January 2017