Table 3.

Experimental design matrix and results

RUN	Experimental design
	pH	$\frac{[GO]}{[AgN{O}_3]}$	Loaded silver
1	−1	−1	3.42
2	−1	+1	4.52
3	+1	−1	1.90
4	+1	+1	3.25
5	0	−1	2.00
6	0	+1	2.51
7	−1	0	3.92
8	+1	0	4.31
9	0	0	5.27
10	0	0	5.07
11	0	0	4.97
12	0	0	5.17
13	0	0	5.00