Table 1. Typical ORR Results Obtained from GC, CNT, NP, and NS Catalysts Measured in 0.1 M KOH and 0.5 M PBS pH 7.0^a.

catalyst	solution	onset potential/mV	Tafel slope/mV/dec	jk@0.62 V	io	no. of e–n
Pt/C	KOH	962	120.9	76.72	7.55	3.885
GCE	KOH	700	78.5	0.52	4.08	1.874
CNT	KOH	800	106.2	1.01	4.39	1.884
NP	KOH	932	113.6	4.40	5.56	2.847
NS	KOH	945	106.9	6.80	5.76	2.786
Pt/C	PBS	645
GCE	PBS	316	191.9	1.99	1.15	1.12
CNT	PBS	545	168	17.14	2.31	2.20
NP	PBS	546	135.4	200	2.46	2.84
NS	PBS	553	124.3	1348	2.64	2.85

^aAll of the potentials were reported versus RHE.