*2.1. Synthesis of the Catalyst*

The bimetallic Fe/Ni-BDC catalyst was synthesized by the solvothermal method [27–29]. Typically, a clear solution containing H2BDC (9 mmol, Sigma-Aldrich, Saint Louis, MO, USA), FeCl3·6H2O (6 mmol, Fisher Scientific, Hampton, NH, USA), and Ni(NO3)2·6H2O (1.8 mmol, Fisher Scientific, Hampton, NH, USA) in 60 mL of *N*,*N*-dimethylformamide (DMF, 99%, Xilong Chemical Co., Ltd., Guangzhou, China) was prepared and placed in a pressure device (100 mL Hydrothermal Synthesis Autoclave Reactor 304 Stainless Steel High-Pressure Digestion Tank with PTFE Lining for Rapid Digestion of Insoluble Material, Baoshishan, Shanghai, China). Then, this device was placed in an oven (Memmert UN110, Schwabach, Germany) at 100 ◦C for three days. The non-reacted components, such as the remains of the organic linker in porous holes was elimated by a distillation router with DMF solvent at 100 ◦C for a day. The orange solid was washed in DMF solvent (three times) and water (three times), followed by drying for a day at 60 ◦C. For comparison, Ni-BDC and Fe-BDC catalysts were also synthesized via the same method as for the synthesis of Fe2Ni-BDC by using Ni(NO3)2·6H2O for the synthesis of Ni-BDC and FeCl3·6H2O for the synthesis of Fe-BDC. The catalyst products obtained were an orange solid and a green solid for the Fe-BDC and Ni-BDC materials, respectively.
