Alkanolamine intercalation assisted liquid phase exfoliation of titanium carbide MXene nanosheets for highly efficient photocatalytic CO2 reduction

Two-dimensional titanium carbide (Ti 3 C 2 T x ) MXene nanosheets have been widely concerned due to its abundant surface functional groups, high conductivity, excellent photoelectrochemical properties and thermal conductivity. Nevertheless, it is still a challenge for the mass production of high-quality Ti 3 C 2 T x MXene nanosheets. Herein, the bulk Ti 3 C 2 T x MXene powders were stripped into monolayer or few layer nanosheets in propylene carbonate through liquid-phase exfoliation strategy assisted via alkanolamine as intercalators. It is shown that the stripping yield is up to 59.3 %, which is the recorded value for the delamination of Ti 3 C 2 T x MXene nanosheets from bulk Ti 3 C 2 T x MXene powder, and 62.2 % of nanosheets are monolayer. The ability of hydrogen bond donor and molecular size of alkanolamine have important effects on the yield. Moreover, Ti 3 C 2 T x MXene nanosheets have been employed as catalysts in the photocatalytic CO 2 reduction. The yield of CO is 149.7 μmol g -1 h −1 , which is about five times that of bulk Ti 3 C 2 T x MXene powder. This work paves the way for the mass production of MXene nanosheets with high activity photocatalysis.