Improved Carrier Separation and Recombination by Ferroelectric Polarization in the CuBiP<sub>2</sub>Se<sub>6</sub>/C<sub>2</sub>N Heterostructure: A Nonadiabatic Molecular Dynamics Study
Xingxing Jiang, Jieyao Tan, Dongyu Liu, Yexin Feng, Ke‐Qiu Chen, Run Long, Andrey S. Vasenko
Abstract
The rapid recombination of photogenerated carriers heavily restricts the photocatalytic efficiency. Here, we propose a new strategy to improve catalytic efficiency based on the ferroelectric van der Waals heterostructure (CuBiP 2 Se 6 /C 2 N). Combining density functional theory and the nonadiabatic molecular dynamics (NAMD) method, we have systematically analyzed the ground-state properties and carrier dynamics images in the CuBiP 2 Se 6 /C 2 N heterostructure. Our calculations showed that the ferroelectric polarization of CuBiP 2 Se 6 provides the internal driving force for the photogenerated carriers separation. NAMD results demonstrate that the excited-state carrier transfer and recombination processes in the CuBiP 2 Se 6 /C 2 N are consistent with a type II mechanism. Meanwhile, constructing the ferroelectric heterostructure can effectively prolong the carrier lifetime, from ∼65.98 to ∼124.54 ps. Moreover, the high quantum efficiency and tunable band edge positions mean that the CuBiP 2 Se 6 /C 2 N heterostructure is an excellent potential candidate material for photocatalytic water splitting.