Fig. 2: Electrochemical behaviors and electrochemical spectra of [Os] complexes.

a CV curves of 1.0 mM of przpOs and trzpOs in electrolyte of 0.1 M n-Bu4NPF6 acetonitrile solution, in N2 atmosphere, at scan rate of 0.1 V s−1 and without iR correction. The arrows indicate the scanning direction. CV curves of przpOs (b) and trzpOs (c) in N2 and CO2 saturated electrolyte with the addition of 1.0 mM TFA. d Current-time curves of przpOs and trzpOs in N2 and CO2 at −1.4 VNHE, under chopped AM 1.5 G illumination. e Gas products of przpOs and trzpOs in CO2 at −1.4 VNHE determined by GC measurements. In situ UV-vis spectro-electrochemistry of 1.0 mM przpOs (f) and trzpOs (g) in N2 and CO2 saturated electrolyte at different applied potentials. The inset figure shows the proposed catalytic cycles.