Computational Search for Two-Dimensional Photocatalysts

TL;DR

This study uses high-throughput first-principles calculations to identify promising two-dimensional heterostructures for photocatalytic water splitting, providing a comprehensive database to guide experimental design.

Contribution

It introduces a large-scale computational screening of 2D heterostructures for photocatalysis, including a detailed band alignment database for 260 monolayers.

Findings

Identified dozens of promising 2D semiconductors for water splitting.

Created a comprehensive band alignment database for 260 monolayers.

Screened thousands of heterostructures for photocatalytic potential.

Abstract

To overcome current serious energy and environmental issues, photocatalytic water splitting holds great promise because it requires only solar energy as an energy input to produce hydrogen. Two-dimensional (2D) semiconductors and heterostructures possess several inherent advantages which are more suitable for boosting solar energy than their bulk counterparts. In this work, by performing high-throughput first-principles calculations combined with a semiempirical van der Waals dispersion correction, we first provided the periodic table of band alignment type for van der Waals heterostructures when packing any two of the 260 semiconductor monolayers obtained from our 2D semiconductor database (2DSdb) (https://materialsdb.cn/2dsdb/index.html). Based on the rules of thumb for photocatalytic water splitting, we have further screened dozens of potential semiconductors and thousands of heterostructures which are promising for photocatalytic water splitting. The resulting database would provide a useful guidance for experimentalists to design suitable 2D vdWHs and photocatalysts according to desired applications.