Table 1. Total Number of Acid Sites of the Prepared Samples.

sample	Ei (Mv)	no. of acid sites*10–20	quinoxaline (%)	xanthene (%)
Fe-MOF	165.1	2.81	66.32	41.76
Co-MOF	141.4	2.34	53.45	32.5
10%Fe:90%Co-MOF	182.2	3.12	74.50	60.00
30%Fe:70%Co-MOF	230.6	4.31	86.88	78.99
50%Fe:50%Co-MOF	291.2	5.62	94.30	87.45
70%Fe:30%Co-MOF	250.0	4.73	90.11	81.03
90%Fe:10%Co-MOF	198.4	3.44	79.15	73.26