Figure 3.

LSVs obtained with a Cu foam electrode in (a) pH 2, (b) pH 4.5, (c) pH 7, and (d) pH 9 buffered solutions with (red) and without (black) 20 mm HMF (scan rate: 10 mV s−1).

LSVs obtained with a Cu foam electrode in (a) pH 2, (b) pH 4.5, (c) pH 7, and (d) pH 9 buffered solutions with (red) and without (black) 20 mm HMF (scan rate: 10 mV s−1).