Fabricating Lattice‐Confined Pt Single Atoms With High Electron‐Deficient State for Alkali Hydrogen Evolution Under Industrial‐Current Density

Abstract

Abstract The confining effect is essential to regulate the activity and stability of single‐atom catalysts (SACs), but the universal fabrication of confined SACs is still a great challenge. Here, various lattice‐confined Pt SACs supported by different carriers are constructed by a universal co‐reduction approach. Notably, Pt single atoms confined in the lattice of Ni(OH) 2 (Pt 1 /Ni(OH) 2 ) with a high electron‐deficient state exhibit excellent activity for basic hydrogen evolution reaction (HER). Specifically, Pt 1 /Ni(OH) 2 just requires 15 mV to get 10 mA cm −2 and the mass activity of Pt 1 /Ni(OH) 2 is 15 times of commercial Pt/C. Moreover, Pt 1 /Ni(OH) 2 assembled in an alkaline water electrolyzer shows 1030 h durability under the industrial current density of 800 mA cm −2 . In situ spectroscopy techniques reveal Pt─H and “free” OH radical can be directly observed for Pt 1 /Ni(OH) 2 , confirming the lattice‐confined Pt single atoms play a key role during HER. Further density functional theory uncovers the Pt 3d orbital strongly hybridizes with O 2p and Ni 3d orbitals in Ni(OH) 2 , which quickly optimizes the electronic state of the Pt site, thus largely reducing the energy barrier of the rate‐determining step to 0.16 eV for HER. Finally, this synthesis method is extended to construct other 9 lattice‐confined SACs.