Construction of CdLa2S4/MIL-88A(Fe) heterojunctions for enhanced photocatalytic H2-evolution activity via a direct Z-scheme electron transfer

Abstract A novel Z-scheme CdLa2S4/MIL-88A(Fe) heterojunction was successfully designed and fabricated through loading CdLa2S4 on MIL-88A(Fe). The phase, morphologies, microstructures, and photoelectric characteristics of the constructed Z-scheme photocatalyst were investigated in detail. The photocatalytic activity of the obtained material under visible light was assessed via the photocatalytic H2 generation. It was shown that the CdLa2S4 nanoparticles were uniformly anchored on the MIL-88A(Fe) microrods with an intimate interface. With such a unique structure, the obtained CdLa2S4/MIL-88A(Fe) composites demonstrated excellent photocatalytic H2-evolution performance. When the content of MIL-88A(Fe) was 20 wt%, the CdLa2S4/MIL-88A(Fe) presented the maximal H2-generation rate of 7677.5 μmol·h-1·g-1 (apparent quantum yield of 10.3% at 420 nm), which was nearly 7.73 times that of pristine CdLa2S4. The high photocatalytic activity was mainly contributed to the formed Z-scheme structure which facilitated the separation of photoexcited electron-hole pairs.