Currently,
atomically thin materials with high photovoltaic performance
are urgently needed for applications in solar cells. Herein, by using
first-principles calculations, we propose an excellent two-dimensional
photovoltaic material, monolayer HfTeSe4, which can be
exfoliated feasibly from its layered bulk. It behaves in the semiconductor
character with a moderate direct gap of 1.48 eV and exhibits remarkable
absorbance coefficient of ∼105 cm–1 in the visible-light region. Meanwhile, monolayer HfTeSe4 shows ultrahigh photocurrent and a long carrier recombination lifetime.
Also, strain engineering can further modulate the recombination time
of carriers. Moreover, the heterostructure between HfTeSe4 and Bi2WO6 is proposed as potential solar
cells with the solar conversion efficiency up to ∼20.8%. These
extraordinary properties combined with its experimental feasibility
makes monolayer HfTeSe4 particularly promising for photovoltaic
device applications.