Fig. 2: CO₂RR performances.

a, b The linear sweep voltammetry curves (a) and potential-dependent Faradaic efficiencies for products (b) on ZnIn₂S₄ and In₂S₃. c, d Partial current density (c) and half-cell PCE (d) for CO₂-to-formate conversion on ZnIn₂S₄ and In₂S₃. e, f Comparison of formate partial current densities and FEs (e), and formate production rates (f) for various catalysts reported under KHCO₃ environments (see Supplementary Table 1 for details). g Stability test of the ZnIn₂S₄ and In₂S₃ at 300 mA cm⁻². The electrolyte was occasionally replaced by new 1 M KHCO₃ solution (red arrows) to recover the ionic concentration and conductivity of the anolyte. The error bars represent the standard deviation of three independent measurements.