Fig. 4: Characterizations on the intermediates.
From: Electrocatalytic water oxidation with manganese phosphates
The ex-situ potential-dependent EPR spectra of KMnPO4 (a) and KMnPO4•H2O (b). The in-situ potential-dependent UV-vis (c, d) and in-situ Raman (e, f) spectra of KMnPO4 (c, e) and KMnPO4•H2O (d, f ) (The solution resistance is 138.7 ± 1.2 Ω). g The potential responses of the two electrocatalysts to the pH values of the electrolyte at Epa (MnIII/IV). The error bars were the standard deviations of three repeated measurements. The electrochemical responses of KMnPO4 (h) and KMnPO4•H2O (i) in electrolytes with different pH values. (The solution resistances are 145.6 ± 2.0 Ω (pH = 6.79), 138.7 ± 1.2 Ω (pH = 6.99), 136.6 ± 2.2 Ω (pH = 7.21), 135.9 ± 1.9 Ω (pH = 7.38), 133.0 ± 0.6 Ω (pH = 7.58), respectively). All standard deviations were obtained by three repeated measurements.
