The load of Pd in NH2-MIL-125 was prepared by the same procedure as that for pure NH2-MIL-125, except that 0.3 mmol Pd(PPh3)4 was added into the mixture during hydrothermal process. Triphenylphosphine was oxidized into triphenylphosphine oxide, which was mostly removed by filtration. The Pd loading of Pd-doped NH2-MIL-125 (Ti) was measured to be 2.8 wt% based on ICP-AES testing.