Abstract 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.

中文翻译：

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Ti3C2 MXene 桥接的 Ag/Ag3PO4 杂化物增强可见光驱动的光催化活性

摘要 作为一种新型的过渡金属碳化物和/或碳氮化物，MXene 具有二维特性、丰富的表面亲水官能团和优异的导电性，为构建 MXene 基光催化剂提供了可能。受此启发，报道了一种新兴的 Ti3C2 MXene 助催化剂桥接 Ag/Ag3PO4 以诱导高度可见光驱动的光催化活性，通过静电自组装方法合成，并在 MXene 溶液中将 Ag+ 离子部分还原为 Ag0。由此产生的混合体揭示了一个明确的混合结构，Ag/Ag3PO4 锚定在层状结构的 Ti3C2 纳米片上。得益于独特的结构特点，Ag/Ag3PO4/Ti3C2 杂化物在可见光照射下对甲基橙 (MO) 降解和 Cr(VI) 还原具有 Ti3C2 含量依赖性光催化活性。值得注意的是，含有 3 wt% Ti3C2 的 Ag/Ag3PO4/Ti3C2 杂化物在辐照 1 小时后实现了最大的 MO 降解效率和 Cr(VI) 还原效率，分别比原始 Ag3PO4 纳米颗粒提高了 1.72 倍和 1.46 倍， 分别。这种令人印象深刻的光催化活性与源自 Ag、Ag3PO4 和 Ti3C2 的协同效应有关，它们极大地增强了可见光吸收，促进了光生电子-空穴对的分离和转移。