Improvement of Visible-Light Photocatalytic Efficiency in a Novel InSe/Zr₂CO₂ Heterostructure for Overall Water Splitting

Abstract

The unexpected visible-light absorption, low recombination of electron−hole pairs, and high carrier mobility are found in a novel two-dimensional (2D) InSe/Zr 2 CO 2 van der Waals heterostructure for overall water splitting photocatalysis. The photocatalytic mechanism has been systematically investigated using first-principles calculations for the first time. We prove that the 2D InSe/Zr 2 CO 2 heterostructure is a robust and promising visible-light photocatalyst with several distinct advantages, as follows. It has a direct band gap of 1.81 eV, which is a more favorable band gap for visible-light photocatalysis. Its type-II band alignment directly leads to a significant electron−hole separation with electrons (holes) localized in the InSe (Zr 2 CO 2 ) monolayer. The indirect band gap of the InSe (Zr 2 CO 2 ) monolayer further suppresses the electron−hole recombination in it. Naturally, the recombination of the photogenerated electrons and holes is greatly suppressed in the InSe/Zr 2 CO 2 heterostructure, which improves the solar energy utilization effectively. Moreover, a large optical absorption coefficient (10 5 cm −1 ) has been confirmed in the 2D InSe/Zr 2 CO 2 heterostructure with the electron (hole) mobility reaching up to 10 4 (10 3 ) cm 2 V −1 s −1 , which is highly beneficial and desirable for enhancing its photocatalytic efficiency.

High-throughput screening of two-dimensional materials and prediction of photocatalytic performances

“…例如, 在α-P中随着层数的增加, 带 隙不断减小, 如图4(c)所示 [7] . 此外, Mir等人 和态密度(density of states, DOS), 可以发现这种结构因 为CBM位于InSe层, 而VBM位于Zr 2 CO 2 层, 因此电子从 VBM受光激发跃迁到CBM后, 电子-空穴的复合率将明 显降低 [45] , 关于异质结结构将在3.3节中具体讨论. 事实上, 通过第一性原理计算可以预测材料的光 学性能.…”

“…相比之下, 基于Bardeen和Shockley [39] 提出的DP理论虽然也考虑长声学波声子的散射作用, 但忽略了其他一些散射, 如光学波声子散射 [40] , 因此计 算结果往往偏大. 实际上, 当长声学波声子的影响较大 而光学波声子影响较小时, 一些计算结果在数量级上 与实验值是吻合的, 如MoS 2 [44] 、InSe [45] 和TiS 3 [46] 等.…”

High‐Performance Near‐Infrared Photodetectors Based on Surface‐Doped InSe

“…[ 13 ] Moreover, InSe has a markedly high electron mobility (≈1000 cm 2 V −1 S −1 ) thanks to the small electron effective mass, and it has a low electron‐hole recombination rate, allowing high photoresponse. [ 14–16 ] However, most studies on InSe‐based photodetectors have focused on the visible wavelength regime. [ 17–21 ] A few reports show InSe photodetectors sensing IR light, [ 22–27 ] but their performance is limited.…”

Significantly Raised Visible‐Light Photocatalytic H2 Evolution on a 2D/2D ReS2/In2ZnS4 van der Waals Heterostructure

“…[ 5,10,12,13,15,23,25,29,33,34,38,42–51 ] Of particular interest are 2D/2D van der Waals heterostructures (vdWHs). This is because of wide applications in catalysis, [ 52,53 ] electronics, [ 44,45 ] sensing, [ 46,47 ] and optoelectronics. [ 48,49 ] 2D/2D vdWHs exhibit intrinsic advantages in photocatalysis applications, namely: [ 52,53 ] 1) tunable light‐absorption spectrum via combining 2D materials with diverse bandgap widths; 2) unique layer‐on‐layer interaction with ultrahigh interfacial area and intimate electronic coupling; 3) interfacial photoinduced electron–hole dissociation and migration; 4) optimized electronic structure for advanced catalytic performance, arising from intimate interlayer electronic interaction; 5) diversity for integration with a range of new 2D building blocks, such as graphyne, borocarbonitrides, antimonene and transition metal phosphorus trisulfides (MPS 3 ).…”