Ti3C2 MXene-bridged Ag/Ag3PO4 hybrids toward enhanced visible-light-driven photocatalytic activity

As a novel transition metal carbides and/or carbonitrides, MXene possess two-dimensional characteristic, abundant surface hydrophilic functional groups, and excellent electrical conductivity that bestow a possibility to building MXene-based photocatalysts. Inspired by this, an emerging Ti3C2 MXene cocatalyst bridged Ag/Ag3PO4 to induce a highly visible-light-driven photocatalytic activity, synthesized by electrostatic self-assembly method and the partial reduction of Ag+ ions to Ag-0 in MXene solution is reported. The resultant hybrids reveal a well-defined hybrid structures with Ag/Ag3PO4 anchoring on the layer structured Ti3C2 nanosheets. Benefiting from the unique structural features, the Ag/Ag3PO4 /Ti3C2 hybrids present Ti3C2 content-dependent photocatalytic activity toward the methyl orange (MO) degradation and Cr(VI) reduction under visible-light irradiation. Remarkably, the Ag/Ag3PO4 /Ti3C2 hybrid with 3 wt% Ti3C2 content achieves the greatest MO degradation efficiency and Cr(VI) reduction efficiency after irradiation for 1 h, which are increased to 1.72 and 1.46 times higher than that obtained on pristine Ag3PO4 nanoparticles, respectively. Such impressive photocatalytic activity is related to the synergeric effects derived from Ag, Ag3PO4, and Ti3C2, which greatly enhance visible light absorption, promote separation and transfer of photo-generated electron-hole pairs. This work highlights that the MXene-based photocatalysts would be desirable candidates for environmental purification of organic pollutants and heavy metal ions.