用于氢燃料电池中电催化剂载体材料的MAX相表面的密度泛函理论研究

DFT Study of MAX Phase Surfaces for Electrocatalyst Support Materials in Hydrogen Fuel Cells.

作者信息

Gertzen Jonathan, Levecque Pieter, Rampai Tokoloho, van Heerden Tracey

机构信息

HySA/Catalysis Centre of Competence, Catalysis Institute, Department of Chemical Engineering, University of Cape Town, Cape Town 7700, South Africa.

Department of Chemical Engineering, University of Cape Town, Cape Town 7700, South Africa.

出版信息

Materials (Basel). 2020 Dec 25;14(1):77. doi: 10.3390/ma14010077.

DOI:10.3390/ma14010077

PMID:33375752

原文链接:https://pmc.ncbi.nlm.nih.gov/articles/PMC7796375/

Abstract

In moving towards a greener global energy supply, hydrogen fuel cells are expected to play an increasingly significant role. New catalyst support materials are being sought with increased durability. MAX phases show promise as support materials due to their unique properties. The layered structure gives rise to various potential (001) surfaces. DFT is used to determine the most stable (001) surface terminations of TiAlC, TiAlC and TiSiC. The electrical resistivities calculated using BoltzTraP2 show good agreement with the experimental values, with resistivities of 0.460 µΩ m for TiAlC, 0.370 µΩ m for TiAlC and 0.268 µΩ m for TiSiC. Surfaces with Al or Si at the surface and the corresponding Ti surface show the lowest cleavage energy of the different (001) surfaces. MAX phases could therefore be used as electrocatalyst support materials, with TiSiC showing the greatest potential.

摘要

在迈向更绿色的全球能源供应过程中，氢燃料电池有望发挥越来越重要的作用。人们正在寻找具有更高耐久性的新型催化剂载体材料。MAX相因其独特性能有望成为载体材料。其层状结构产生了各种潜在的（001）表面。采用密度泛函理论（DFT）来确定TiAlC、TiAlC和TiSiC最稳定的（001）表面终止结构。使用BoltzTraP2计算的电阻率与实验值吻合良好，TiAlC的电阻率为0.460 μΩ·m，TiAlC的电阻率为0.370 μΩ·m，TiSiC的电阻率为0.268 μΩ·m。表面有Al或Si以及相应Ti表面的（001）表面在不同（001）表面中具有最低的解理能。因此，MAX相可用作电催化剂载体材料，其中TiSiC显示出最大潜力。