2. Comparisons between Taffit and CTA for Literature Tafel slopes.

catalyst	Taffit slope (mV/dec)	lit. slope (mV/dec)	percent relative difference (%)
CoP3	–70.0	–78 ± 2	11
FeP2	–128	–129 ± 11	0.85
NiP2 cubic	–66.9	–91 ± 4	31
NiP2 mono	–77.2	–81 ± 2	4.8
10% Pt-C	–65.5	–34 ± 2	63
Co0.5Ni0.5Se2	–57.4	–55	4.3
CoSe2	–42.8	–47	9.4

^a n = 2 was used in Taffit analysis.