Carbon cloth supporting (CrMnFeCoCu)3O4 high entropy oxide as electrocatalyst for efficient oxygen evolution reactions

High-entropy oxides (HEOs) have received more attentions for the oxygen evolution reaction (OER) due to their rich active sites and high configurational entropy. However, the difficulty of electron transfer during the catalysis process limits the application of HEOs in OER catalysis. Herein, we proposed the carbon cloth (CC) supporting (CrMnFeCoCu)3O4 HEO with spinel structure synthesized by the hydrothermal method following with the calcination. The carbon cloth used as the support of HEO could improve the conductivity and stability of the catalyst. Meanwhile, the excellent catalytic activity of HEO with the synergistic effects of multiple metal elements would be maintained. And the homo-disperse HEO nanoparticles were exposed on the surface carbon fibers, which was conducive to contact with electrolyte. Based on the above merits, the intrinsic catalytic activity of (CrMnFeCoCu)3O4/CC was enhanced, which was attributed to the self-regulating electronic structure and the fine HEO nanoparticles exposed on the surface of catalysts. And the catalytic kinetic process of (CrMnFeCoCu)3O4/CC was accelerated, mainly due to its conductivity and richer oxygen vacancies. The (CrMnFeCoCu)3O4/CC exhibited the outstanding OER performance with an ultralow overpotential (210.8 mV @10 mA·cm−2), a smaller Tafel slope value (59.4 mV·dec−1), and super long-term durability, which was competitive with other transition metal oxides based catalysts and noble metal oxides. Therefore, the excellent OER performance implied that the (CrMnFeCoCu)3O4/CC is an OER catalyst candidate for practical application.