In situ evolution of the active phase on stainless steel mesh toward a cost-effective bifunctional electrode for energy storage and conversion.

Developing low-cost, efficient and stable electrode materials is a major challenge of energy storage and conversion. Here, we report a facile, cost-effective and scaled-up self-sacrificing strategy for transforming commercial stainless steel into highly active and ultrastable electrodes for supercapacitors and the hydrogen evolution reaction. The modified stainless steel displays superior electrochemical activity as well as excellent cycling durability.