Carbon supported PtCo nanoparticles in-situ derived from ZIF-67 boosting methanol assisted water electrolysis

Efficient Pt-based catalysts for both hydrogen evolution reaction (HER) and methanol oxidation reaction (MOR) in acid media still remains a great challenge. Herein, porous cubic N-doped carbon supported PtCo alloy with high dispersion and small size was successfully synthesized derived from the zeolite imidazole frameworks (ZIFs). Benefiting from the strong support from N-doped carbon, PtCo exhibited an optimized electronic structure and improved exposed active sites of Pt species, thus leading to an excellent bi-activity toward HER and MOR in HClO 4 media. In detail, the optimum catalyst with a low-loading Pt of 3.63 wt% delivered the current density of 10 mA cm −2 at a low overpotential of 14 mV, and exhibited a superior Tafel slope of 20.22 mV dec −1 as well as a strong stability for 12 h continuous operation without obvious change toward the HER. In the meantime, this catalyst also showed a high mass activity of 1852 mA mg −1 along with a better resistance to CO poisoning toward the MOR. Moreover, the coupled electrolyzer of MOR||HER based on this bifunctional catalyst required a voltage of 1.484 V at 10 mA cm −2 , lower than the overall water splitting (0.151 V), obviously outperformed that on benchmark commercial 20 wt% Pt/C (JM) (1.662 V). This work might provide a great insight for the functionalized design of bifunctional electrocatalysts and beyond.