Synthetic parameters of the Cu@Co-MOFs samples.

Sample	n(Co(NO3)2·6H2O)/mM	n(Cu(NO3)2·3H2O)/mM	n(BDC)/mM	Co2+/Cu2+	(Cu2+ + Co2+)/BDC
Cu@Co-MOFs-1	2.4	9.6	12	1 : 4	1 : 1
Cu@Co-MOFs-2	4.8	7.2	12	2 : 3	1 : 1
Cu@Co-MOFs-3	6	6	12	1 : 1	1 : 1
Cu@Co-MOFs-4	7.2	4.8	12	3 : 2	1 : 1
Cu@Co-MOFs-5	9.6	2.4	12	4 : 1	1 : 1
Cu@Co-MOFs-6	6	6	18	1 : 1	2 : 3
Cu@Co-MOFs-7	6	6	18	1 : 1	3 : 2