Waste is the best: end-of-life lithium ion battery-derived ultra-active Ni3+-enriched β-Ni(OH)2 for the electrocatalytic oxygen evolution reaction

The recovery of Ni as Ni(DMG) 2 and subsequently as Ni 3+ -rich β-Ni(OH) 2 from spent LIBs is reported. The presence of Ni 3+ in the as-synthesized β-Ni(OH) 2 results in its exceptional electrocatalytic OER activity without any oxidative pre-treatment.