A greener route to steel

Metals production is the largest industrial source of greenhouse gases, with steel the main culprit. Traditional methods of extracting iron from its ore require a carbon-based reductant and produce large quantities of CO₂. Molten oxide electrolysis is a promising alternative, but until now it has required anode materials that are either consumable or prohibitively expensive. This paper reports the development of a new chromium-based aluminium alloy electrode that is relatively cheap and, thanks to its three-layered structure (metal oxide/mixed oxide/electrolyte), is protected from dissolution. This technology must now be scaled up and its long-term performance assessed.