Single-site Co-anchored α- In2Se3 with enhanced and polarization-dependent hydrogen and oxygen evolution activity.

Electroreduction of water into hydrogen holds promise to deal with growing environmental pollution and energy crisis, but it relies on efficient catalysts for both hydrogen/oxygen evolution reaction, that normally contain precious metal. Here, based on first principles calculations, we identify Co-anchored α-In 2 Se 3 as a bifunctional catalyst that can operate for both hydrogen/oxygen evolution reaction. The chemical activity can be largely enhanced or optimized by electrostatic potential due to the polarization, even better than traditional one containing precious metal. Both hydrogen/oxygen evolution reaction are dependent on polarization direction of α-In 2 Se 3 and could occur on different polarization domains separately of α-In 2 Se 3 , that providing a way for future design of bifunctional catalysts without precious metals based on two-dimensional ferroelectric substrate. • The effect of polarization for the HER and OER activity of Co atom supported on α-In 2 Se 3 has been investigated by DFT. • The activity of TM atom can be largely enhanced or optimized by electrostatic potential due to the polarization. • The stability of the single atom catalysts and the mechanism for enhancing catalytic reactions have been fully discussed. [ABSTRACT FROM AUTHOR]