Single atom catalyst, which contains isolated metal atoms singly dispersed on supports, has great potential for achieving high activity and selectivity in hetero-catalysis and electrocatalysis. However, the activity and stability of single atoms and their interaction with support still remains a mystery. Here we show a stable single atomic ruthenium catalyst anchoring on the surface of cobalt iron layered double hydroxides, which possesses a strong electronic coupling between ruthenium and layered double hydroxides. With 0.45 wt.% ruthenium loading, the catalyst exhibits outstanding activity with overpotential 198 mV at the current density of 10 mA cm−2 and a small Tafel slope of 39 mV dec−1 for oxygen evolution reaction. By using operando X-ray absorption spectroscopy, it is disclosed that the isolated single atom ruthenium was kept under the oxidation states of 4+ even at high overpotential due to synergetic electron coupling, which endow exceptional electrocatalytic activity and stability simultaneously.
展开▼
机译：单原子催化剂包含单独分散在载体上的孤立的金属原子，具有在杂化催化和电催化中实现高活性和选择性的巨大潜力。但是，单个原子的活性和稳定性以及它们与载体的相互作用仍然是个谜。在这里，我们显示了固定在钴铁层状双氢氧化物表面上的稳定单原子钌催化剂，该催化剂在钌和层状双氢氧化物之间具有强电子耦合。钌负载量为0.45 wt。％时，在电流密度10 mA cm -2 和Tafel斜率小的39 mV dec -1 时表现出出色的活性，超电势为198 mV。支持>放氧反应。通过操作X射线吸收光谱，公开了由于协同电子耦合，分离的单原子钌甚至在高过电势下也保持在4+的氧化态，这同时赋予了优异的电催化活性和稳定性。
展开▼
