Advancements in recycling techniques for hydrogen technologies with focus on electrolysers

The accelerated global demand for clean energy has significantly increased the deployment of hydrogen technologies, positioning electrolysers as vital to achieving net-zero ambitions. However, as key components of the green hydrogen economy, electrolysers utilise noble-metal catalysts, advanced membranes, and critical raw materials that pose unique challenges for establishing a circular economy. To address resource scarcity, elevated material costs, and environmental concerns, recycling methods such as hydrometallurgy and pyrometallurgy, along with emerging approaches such as transient electrochemical dissolution, biometallurgy, and selective recovery techniques, have been investigated. These R-technologies have varying maturity levels in scalability, efficiency, and ecological impacts, but face challenges due to the complex material composition of electrolysers, component degradation during operation, and the lack of standardised processes for efficient material separation and recovery at end-of-life. Here, we present advancements in recycling techniques for hydrogen technologies, with a distinctive focus on integrating design-for-recycling principles and exploring innovative recovery methods for electrolysers. The review critically evaluates established and emerging recycling strategies, assessing key challenges such as material degradation, system complexity, and manufacturing variability, alongside economic and environmental barriers, including high recovery costs and limited infrastructure. Gaps in scalable recovery of critical metals, especially iridium, and the role of life-cycle assessment and interdisciplinary approaches in developing efficient, low-impact recycling solutions are highlighted. Alongside advocating strategic investments in research and infrastructure, as well as regulatory policies, this review assesses actionable pathways to develop cost-effective and sustainable recycling systems. These efforts aim to drive the global shift toward resource-efficient and circular hydrogen production.