Preparation and application method of DO-CoBi-MOFs nano-catalyst applied to difunctional photocatalytic synthesis of ammonia

The invention discloses a preparation method of a DO-CoBi-MOFs nano-catalyst applied to difunctional photocatalytic synthesis of ammonia (namely compressed air and nitrate are respectively used as reactants). The preparation method comprises the following steps: S1, adding 7.2 mg of Bi (NO3) 2.3 H2O; dissolving 60mg of PVP (Polyvinyl Pyrrolidone) into 24mL of mixed solution of DMF (Dimethyl Formamide) and absolute ethyl alcohol (V: V = 3: 1); then, 4.4 mg of Co (NO3) 2.6 H2O and 0.8 mg of pyrazine are dissolved in the mixed solution; s2, dissolving 8.0 mg of TCPP and 0.01 mmol of TCPP into 8 mL of a mixed solution of DMF (Dimethyl Formamide) and ethanol; s3, then, slowly injecting the solution S2 into the solution S1 under violent stirring (500-1000r/min), and then carrying out ultrasonic treatment for 30 minutes; and finally, transferring the mixed solution into a 25mL small glass bottle, and heating at 80 DEG C for 24 hours. And S4, washing the obtained material with absolute ethyl alcohol for a plurality o