Sacrificial Agent‐Free Photocatalytic Oxygen Evolution from Water Splitting Over Ag 3 PO 4 /MXene Hybrids

To explore an efficient electron extraction cocatalyst remains an ongoing task to address the rapid recombination and low transfer rate of electron–hole pairs in photocatalytic water splitting. Herein, it is demonstrated that 2D MXene (Ti3C2) with high electron conductivity can act as an effective electron transfer and transport medium after being hybridized with Ag3PO4, a well-documented photocatalyst for oxygen evolution. The obtained Ag3PO4/MXene photocatalysts exhibit a significantly high photocatalytic water oxidation activity under visible light illumination. The optimized hybrid shows a remarkable oxygen-evolving concentration (35.8 μmol L−1), which is 2.6 times higher than that of pure Ag3PO4 nanoparticles. Unprecedentedly, the Ag3PO4/MXene hybrid exhibits a further improved oxygen evolution rate without using the electron sacrificial agent, implying that Mxene nanosheets may act as an electron “pool” that in situ consumes the photogenerated electrons. Other characterizations reveal that the hydrophilic functional groups on the surface of MXene favor the interaction of the photocatalyst with water and in the meantime inhibit the self-corrosion of Ag3PO4 under illumination.