The single-atomic-site doping of oxophilic-metal (Ru) species in FeCo-LDH leads to the active atom reconstruction at symmetry-breaking interfaces and then the excellent catalytic performance for OER/HER and overall water splitting at large current densities.

No abstract

The instability and low large-current-density efficiency for a single atomic metal species system have aroused widespread concern. Herein, the Ru single-atom system constructed on iron–cobalt layered double hydroxide (Rux SACs@FeCo-LDH) exhibits extremely low oxygen evolution reaction (OER) overpotentials of 194 and 246 mV at current densities of 10 and 1000 mA cm− 2, respectively, and high stability beyond 1000 h at 1000 mA cm− 2, far surpassing commercial RuO2. Moreover, its mass activity is ∼2 and 6 times higher than that of Ru and FeCo-LDH, respectively. Extraordinarily, it only needs 1.52 V to achieve 1000 mA cm− 2 current densities for water-splitting, and is almost unchanged after 1000 h, as the highest performance reported so far. Experimental and theoretical calculation results evidence that, partial substitution of oxophilic-Ru atoms to FeCo-LDH triggers the reconstruction at symmetry breaking interfaces, promoting O-O coupling at Ru-O active sites for OER, beneficial for suppressing multiple heteroatomic interface instability under large-current-density water-splitting. Our strategy opens up opportunities for lifting single-atom stability in industrial-scale hydrogen production from water-splitting.