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

Highlights: • An emerging Ti₃C₂ MXene cocatalyst bridged Ag/Ag₃PO₄ hybrids were synthesized. • The hybrids exhibited superior visible-light-driven photocatalytic activity. • Ti₃C₂ MXene promoted separation and transfer of photogenerated electron-hole pairs. • The synergistic effect of Ag, Ag₃PO₄, and Ti₃C₂ contributed to the high 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 Ag⁰ 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.