Modeling and Optimizing Anode Catalyst Layer for Direct Ammonia Fuel Cell

Autor: Fan Dong, Zijun Hu, Ziming Wang, Daijun Yang, Bing Li, Fan Yang, Pingwen Ming, Cunman Zhang, Qiangfeng Xiao
Jazyk: angličtina
Rok vydání: 2023
Předmět:
Zdroj: Energy Nexus, Vol 9, Iss , Pp 100170- (2023)
Druh dokumentu: article
ISSN: 2772-4271
DOI: 10.1016/j.nexus.2022.100170
Popis: Great progress has been made in recent years in the development of low-temperature direct ammonia fuel cells (DAFCs), motivated by the recognition that ammonia is a carbon-free hydrogen carrier with high energy density, low production cost, and ease in liquefaction at ambient temperature. However, the sluggish kinetics of ammonia electrooxidation and especially complicated mass transport in the anode catalyst layer hinder the further development of DAFCs. In this work, a three-dimensional two-phase multicomponent DAFC model considering the effect of ammonia crossover has been developed. Maxwell-Stefan model, Darcy's law and Brinkman equation are utilized to simulate the multicomponent fluid motion and transport. The predicted polarization curve simulates all experimental results well. The model shows the rate of ammonia crossover decreases with the increase of current density. Besides, the effects of the physicochemical property of the anode catalyst layer, including porosity, thickness and PtIr loading, on cell performance are investigated. The modeling results indicate that decreasing porosity and increasing thickness can slightly improve the electrochemical performance of DAFCs at high current density. Meanwhile, higher PtIr loading can effectively reduce voltage loss before approaching the limiting current density.
Databáze: Directory of Open Access Journals