Constructing bi-functional electrocatalysts with multi-active sites is significant to enhance the catalytic performances. However, it is still a large challenge to obtain high efficient catalysts for full water electrolysis. Herein, we design novel sandwich-like FeCo₂O₄@FeCo₂S₄@PPy catalysts through a facile preparation strategy. The as-fabricated samples present an excellent electrocatalytic performance with an overpotential of 98.2 mV for HER at -10 mA cm^-2, 280 mV for OER and a cell voltage of 1.63 V at 50 mA cm^-2. The outstanding performances can be contributed to in-situ electrochemical activation and synergistic effects of electrode materials. It benefits to surface/interface modulation forming active Co and Fe oxyhydroxides in electrochemical reaction process.

构建具有多活性位的双功能电催化剂对于提高催化性能具有重要意义。然而，获得用于全水电解的高效催化剂仍然是巨大的挑战。本文中，我们通过一种简便的制备策略设计了新颖的三明治状FeCo ₂ O ₄ @FeCo ₂ S ₄ @PPy催化剂。制成的样品具有出色的电催化性能，在-10 mA cm ^-2时，HER的过电势为98.2 mV，在OER时为280 mV，在50 mA cm ^-2时电池电势为1.63 V。出色的性能有助于原位电化学活化和电极材料的协同作用。它有助于在电化学反应过程中进行表面/界面调制，形成活性的Co和Fe羟基氧化物。