摘要
Developing bifunctional electrocatalysts for overall water splitting reaction is still highly desired but with large challenges. Herein, an amorphous Fe Co Ni-S electrocatalyst was developed using thioacetamide for the sulfuration of Fe Co Ni hydroxide during the hydrothermal process. The obtained catalyst exhibited an amorphous structure with hybrid bonds of metal-S bond and metal-O bonds in the catalyst system. The optimized catalyst showed a largely improved bifunctional catalytic ability to drive water splitting reaction in the alkaline electrolyte compared to the Fe Co Ni hydroxide. It required an overpotential of 280 m V and 80 m V(No-IR correction) to offer 10 m A/cm^(2)for water oxidation and reduction respectively;a low cell voltage of 1.55 V was required to reach 10 m A/cm^(2)for the water electrolysis with good stability for12 h. Moreover, this catalyst system showed high catalytic stability, catalytic kinetics, and Faraday efficiency for water splitting reactions. Considering the very low intrinsic activity of Fe Co Ni hydroxide, the efficient bifunctional catalytic ability should result from the newly formed hybrid active sites of metallic metal-S species and the high valence state of metal oxide species. This work is effective in the bifunctional catalytic ability boosting for the transition metal materials by facile sulfuration in the hydrothermal approach.
基金
supported by the National Natural Science Foundation of China (No. 21972124)
the Priority Academic Program Development of Jiangsu Higher Education Institution
the support of the Six Talent Peaks Project of Jiangsu Province (No. XCL-070–2018)。