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.Comment: 7 pages, 4 figure