N-configuration engineering in quinoline-linked covalent organic frameworks for selective gold recovery from E-waste leachates.

Pyrene-based COFs with comparable skeletons but distinct diazine-N arrangements were constructed. In Py-COF-Dz, adjacent N sites optimize local interactions and charge redistribution, enabling efficient gold capture with a high uptake of 3384.39 mg g-1, 30 min equilibrium, good selectivity, recyclability, and acidic CPU leachate recovery.