The standard reduction potential of the half cell reaction F2+2e−⇌2F− is 2.87 V.
The standard reduction potential of the half cell reaction Cl2+2e−⇌2Cl− is 1.36 V.
The standard reduction potential of the half cell reaction Br2+2e−⇌Br− is 1.09 V.
The standard reduction potential of the half cell reaction I2+2e−⇌2BI− is 0.54 V.