CO2 reduction reached 76% at pH 9, 53% at pH 8, 42% at pH 10,
and 36% at pH 11. Fig. 6 shows the main products generated in
each case. The production of organic substances was small at pH
11–5.1 ppm C2H5OH and 15.4 ppm CH2O—indicating that CO2
adsorption did not occur to a great extent in this experimental
condition.