Co8FeS8/Fe7S8@N-doped porous carbons as highly efficient and stable electrocatalysts for oxygen evolution reaction

Co8FeS8/Fe7S8@N-doped porous carbons (Co8FeS8/Fe7S8@NC) were prepared via a simple two-step pyrolysis method. Co8FeS8/Fe7S8@NC contains Co8FeS8/Fe7S8, amorphous and graphitic carbon. Existence of a large number of mesopores in the sample was conducive to the transmission of mass and electrons as well as exposure of active sites. Co8FeS8/Fe7S8@NC-0.8 needs overpotentials of 255 and 315 mV to achieve the current density of 10 mA cm(-2) and 100 mA cm(-2), respectively. The lower Tafel slope (59.5 mV dec(-1)) and good durability have also been observed in the Co8FeS8/Fe7S8@NC-0.8. The 2Cdl value of 83.7 mF cm(-2) indicate that the introduction of 0.8 g thiourea could greatly improve the exposure of electrocatalytic active sites. Therefore, this research provides a new perspective for the development of efficient and low-cost electrocatalysts with industrial application prospect.

Automated summary

Co8FeS8/Fe7S8@N-doped porous carbons were synthesized via a simple two-step pyrolysis method. The resulting material exhibited good mass and electron transmission, ample exposure of active sites, and low overpotentials. The addition of thiourea greatly improved the exposure of electrocatalytic active sites.