Fig. 1: Thickness-performance relationship.
a Schematic illustration for ultrathin NiBDC fabrication. b–d TEM images and e–g AFM images (inset is the corresponding height profile measured along the dashed line) of b, e utn-NiBDC, c, f tn-NiBDC, and d, g tk-NiBDC. h Polarization curves of Ni-based MOF catalysts recorded at 1600 rpm and a scan rate of 5 mV s-1, together with the detected HO2- currents on the ring electrode (upper panel) at a fixed potential of 1.2 V vs. RHE (100% iR-corrected). The resistance values of utn-NiBDC, tn-NiBDC, tk-NiBDC, and b-NiBDC are 26.0 ± 1 Ω, 27.5 ± 1 Ω, 29.7 ± 1 Ω and 35.6 ± 1 Ω, respectively. i Corresponding calculated HO2- selectivity. j The polarization curves of utn-NiBDC before and after the stability test (100% iR-corrected). Source data for Fig. 1e–j are provided as a Source Data file.
