In silico screening and design of coating materials for PEMFC bipolar plates

Abstract

Methods used to design coating materials for polymer electrolyte membrane fuel cells (PEMFCs) are unsystematic and time-consuming because current materials research relies on scientific intuition and trial and error experimentation. In this study, a feasible and more efficient scheme of screening and designing coating materials is established based on density function theory (DFT) utilizing the fast-growing computing capacity. The scheme consists of four steps: Elements selection by calculation of Pilling-Bedworth ratio and electrical resistivity, corrosion resistance assessment leveraging the Pourbaix diagram approach, running BoltzTrap code to calculate electrical conductivity (σ/τ) and interface binding strength evaluation by calculation of separation work. According to the calculation results, TiCo and TiCo3 are proposed to be the two most promising candidates because of relatively better properties required by harsh working environment of PEMFC. The high-throughput screening strategy established in this study makes the ideal of rapidly evaluating hundreds of thousands of possible coating materials candidates into reality and helps to indicate the direction of further synthesis efforts.