Fig. 1.

CO₂RR performances of sulfur-doped indium catalysts. a Formation rates of H₂, CO and HCOO⁻ and FE of formate for In foil and S−In catalysts at −0.98 V (versus RHE) for 1 h. b Current density for S2−In catalyst over 1 h of reaction at each given potential (versus RHE). c ECSA-corrected current density and FE of formate for In foil and S2−In catalyst at each given potential for 1 h. d Plot of FE of formate versus current density for S2−In catalyst and some typical catalysts reported to date (see Supplementary Table 1 for details). Reaction conditions: CO₂-saturated 0.5 M KHCO₃ solution in H-type electrochemical cell with platinum plate as the counter electrode and saturated calomel electrode (SCE) as the reference electrode. The experiments in each case were performed at least for three times. The error bar represents the relative deviation