One-dimensional single atom arrays on ferroelectric nanosheets for enhanced CO₂ photoreduction

Single-atom catalysts show excellent catalytic performance because of their coordination environments and electronic configurations. However, controllable regulation of single-atom permutations still faces challenges. Herein, we demonstrate that a polarization electric field regulates single atom permutations and forms periodic one-dimensional Au single-atom arrays on ferroelectric Bi₄Ti₃O₁₂ nanosheets. The Au single-atom arrays greatly lower the Gibbs free energy for CO₂ conversion via Au-O=C=O-Au dual-site adsorption compared to that for Au-O=C=O single-site adsorption on Au isolated single atoms. Additionally, the Au single-atom arrays suppress the depolarization of Bi₄Ti₃O₁₂, so it maintains a stronger driving force for separation and transfer of photogenerated charges. Thus, Bi₄Ti₃O₁₂ with Au single-atom arrays exhibit an efficient CO production rate of 34.15 µmol·g^-1·h^-1, ∼18 times higher than that of pristine Bi₄Ti₃O₁₂. More importantly, the polarization electric field proves to be a general tactic for the syntheses of one-dimensional Pt, Ag, Fe, Co and Ni single-atom arrays on the Bi₄Ti₃O₁₂ surface.