Ligand functionalization on Zr-MOFs enables efficient visible-light-driven H2O2 evolution in pure water

Different ligand functionalized UiO-66 (UiO-66-X, X = OH, (OH)2 and NH2) were prepared and then modified by ZnIn2S4 lamellas to form ZnIn2S4/UiO-66-X heterostructures for visible-light-driven H2O2 evolution in pure water. The H2O2 yields using ZnIn2S4/UiO-66-NH2, ZnIn2S4/UiO-66-(OH)2 and ZnIn2S4/UiO-66-OH are 799, 733 and 165 μmol L−1, respectively, which are 9.5, 8.7 and 2.0 times that of ZnIn2S4/UiO-66. The high performance of ZnIn2S4/UiO-66-NH2 and ZnIn2S4/UiO-66-(OH)2 is ascribed to the benign visible-light response and Z-scheme heterostructures, and the H2O2 evolution abides by indirect O2 reduction with ˙O2− as an intermediate species. Additionally, H2O2 yields using ZnIn2S4/UiO-66-NH2 on tap water and Xuanwu Lake (Nanjing, China) water can be comparable to that on the above-deionized water. This study sheds light on the great promise of functionalized MOFs and their applications on green (photo)catalytic energy conversion.