Table 1. Detailed reaction mechanisms at each intermediate step of oxygen reduction path I described in Fig. 5.

Reaction step	Reaction path
0→1	Sb-OH+O2+2H2O+4e−→Sb-OH(O2)+2H2O+4e−
1→2	Sb-OH(O2)+2H2O+4e−→Sb-OH(OOH)+OH−+H2O+3e−
2→3	Sb-OH(OOH)+OH−+H2O+3e−→Sb-OH(O)+2OH−+H2O+2e−
3→4	Sb-OH(O)+2OH−+H2O+2e−→Sb-OH(OH)+3OH−+e−
4→5	Sb-OH(OH)+3OH−+e−→Sb-OH+4OH−