CoxPy monolayers as ideal materials for electrochemical applications.

[Display omitted] • The authors perform systematic search for high-performance and cost-effective materials toward electrochemical applications for Co-P system via advanced structural prediction. • Current results identified several stable monolayers, such as CoP, Co 2 P, and Co 3 P 2. • Especially, CoP was predicted to become as potential HER catalyst and anode material. • The paper disclosed the possible multifunctional applications for Co x P y monolayers and provided some theoretical guidance in designing electrocatalysts and anode materials from 2D transition-metal materials used in electrochemical processes. Exploring high-performance and cost-effective materials for electrochemical applications to meet eco-friendly and sustainable energy demands remain as an urgent need all the time. Large specific surface area and robust chemical activity endow two-dimensional (2D) materials with the potential as excellent candidates for electrochemical applications. Herein, we systematically study the 2D morphology for the Co-P system via advanced structural search and identify a series of stable monolayers, such as CoP, Co 2 P, and Co 3 P 2. Detailed first-principle calculations reveal that these monolayers showcase inherent metallicity which benefits boosting the electrochemical process. For hydrogen evolution reactions (HER), the activity of CoP could reach 54 meV, which is comparable to that of Pt. As anode material potassium-ion batteries, CoP exhibits a suitable open circuit voltage and high capacity to store metal ion. This work disclosed the possible multifunctional applications for Co x P y monolayers and provided some theoretical guidance in designing electrocatalysts and anode materials from 2D transition-metal materials used in electrochemical processes. [ABSTRACT FROM AUTHOR]