Boosting photocatalytic performance of CdxZn1-xS for H2 production by Mo2C MXene with large interlayer distance

Here we report a novel heterostructure with ultrahigh photocatalytic performance for H<INF>2</INF> production. The heterostructure consists of Cd<INF>x</INF>Zn<INF>1-<INF>x</INF></INF>S solid solution and two dimensional Mo<INF>2</INF>C MXene. The Mo<INF>2</INF>C MXene works as a co-catalyst, which was made from Mo<INF>2</INF>Ga<INF>2</INF>C by etching in cetyltrimethylammonium bromide (CTAB) solution at 160 degrees C for 24 h. Different from the MXene made by the general method of fluoric acid etching, the Mo<INF>2</INF>C MXene made by this method had ultra large interlayer space (lattice parameter c = 24.5 angstrom) due to the in situ intercalation of CTA+. Thereafter, the Mo<INF>2</INF>C MXene without a delamination process was used as the substrate to grow Cd<INF>0.8</INF>Zn<INF>0.2</INF>S (CZS) at room temperature, followed by heating in a hydrothermal process to achieve the phase conversion of CZS from sphalerite to wurtzite. The CZS/Mo<INF>2</INF>C photocatalyst (mass ratio of Mo<INF>2</INF>C : CZS = 0.2 : 1) achieves an ultrahigh photocatalytic H<INF>2</INF> production activity of 44.19 mmol g-1 h-1, surpassing pure CZS by a satisfying factor of approximate to 2289%. It is higher than that of other MXene-co-catalysts and other noble-metal-free CSZ-based photocatalysts reported to date.