Anisotropic Janus SiP2 Monolayer as a Photocatalyst for Water Splitting

Tong Yu, Cong Wang, Xu Yan, Guochun Yang, Udo Schwingenschlögl

Research output: Contribution to journalArticlepeer-review

48 Scopus citations


The design of materials meeting the rigorous requirements of photocatalytic water splitting is still a challenge. Anisotropic Janus 2D materials exhibit great potential due to outstandingly high photocatalytic efficiency. Unfortunately, these materials are scarce. By means of ab initio swarm-intelligence search calculations, we identify a SiP2 monolayer with Janus structure (i.e., out-of-plane asymmetry). The material turns out to be semiconducting with an indirect band gap of 2.39 eV enclosing the redox potentials of water. Notably, the oxygen and hydrogen evolution half reactions can happen simultaneously at the Si and P atoms, respectively, driven merely by the radiation-induced electrons and holes. The carrier mobility is found to be anisotropic and high, up to 10-4 cm2 V-1 s-1, facilitating fast transport of the photogenerated carriers. The SiP2 monolayer shows remarkably strong optical absorption in the visible-to-ultraviolet range of the solar spectrum, ensuring efficient utilization of the solar energy.
Original languageEnglish (US)
Pages (from-to)2464-2470
Number of pages7
JournalThe Journal of Physical Chemistry Letters
StatePublished - Mar 4 2021

ASJC Scopus subject areas

  • General Materials Science


Dive into the research topics of 'Anisotropic Janus SiP2 Monolayer as a Photocatalyst for Water Splitting'. Together they form a unique fingerprint.

Cite this