Fig.1. The absorption spectra of AgNPls (a) CTAB/AgNPls (lmax = 563 nm, A = 0.827);
(b) S2O3
2/CTAB/AgNPls (lmax = 522 nm, A = 0.749); (c) S2O3
2/CTAB/AgNPls + 50
ngmL1 of Cu2+ (A = 0.473); (d) S2O3
2/CTAB/AgNPls + 100 ngmL1 of Cu2+
(A = 0.284); (e) S2O3
2/CTAB/AgNPls + 200 ngmL1 of Cu2+ (A = 0.174). The experiment
was carried out at room temperature in 0.1M ammonia buffer pH 11, The
UV–vis spectrawas investigated after 5 min. (Inset: the color product of the catalytic
etching of modified CTAB/AgNPls with S2O3
2 for measurement of Cu2+).