Fig. 2: Data collection and process.

a The landscape of all V_RHE data produced by experiments, including eighteen conventional and five new perovskites (totally twenty-three perovskites listed as ‘Materials index’ with sequence shown in Table 1). Each perovskite has been made four samples and each sample has been measured three times (totally twelve measurements listed as ‘No. of measurements’). For each measurement, we adopted V_RHE values at five current densities of 50 µA cm⁻², 5 mA cm⁻², 10 mA cm⁻², 15 mA cm⁻², and 20 mA cm⁻². The exact values of those data points are provided in Supplementary Data 1–5. b The flowchart of symbolic regression based on genetic programming (see more details of this flowchart and SR in Supplementary Information).