Material sustainability evaluation of electrocatalysts in early-stage research – case study on La0.6Sr0.4CoO3-δ and La0.6Ca0.4FeO3-δ in alkaline water electrolysis

Sustainable energy materials for energy storage applications are crucial for a reliable energy transition. However, evaluating material sustainability in early stages of energy materials research is a big challenge, as it is difficult to predict the final industrial process and supply chain of the investigated materials. In this work we showcase that a sustainability evaluation can already be conducted in the early stage of electrocatalyst research. We provide a case study of two highly active alkaline oxygen evolution catalysts, La 0.6 Sr 0.4 CoO 3-δ and La 0.6 Ca 0.4 FeO 3-δ , with a thin film model-catalyst approach. For the sustainability evaluation, we consider the material criticality, compare precursor prices, conduct an environmental impact analysis of the precursors based on life cycle assessment and provide a qualitative discourse for social impacts of raw material extraction. We find that La 0.6 Ca 0.4 FeO 3-δ has a reduced environmental footprint, smaller precursor supply risk and 10 times lower precursor price compared to La 0.6 Sr 0.4 CoO 3-δ . However, for both perovskites the high environmental impact and high supply risk of lanthanum is of immediate concern towards larger scale application purposes. Sustainability evaluation in the early stages of energy materials research can be a great opportunity and guidance to identify crucial bottlenecks and to develop new strategies for material selection. This can have a broad impact on later stages of research and development for the energy transition.