Figure 5.

a) Stability evaluation of the Co/BP nanohybrids showing the polarization curves before and after CV cycling. b) Constant potential electrolysis of Co/BP for OER. The black arrows in the red box indicate the fluctuation caused by the bubble released. c) Cyclic voltammograms at different scan rates of Co/BP to estimate of electrochemical active surface area (ECSA). d) Current density variation plotted against scan rate fitted to a linear regression for the estimation of the double layer capacitance (C _dl).