Highly Potassiophilic Graphdiyne Skeletons Decorated with Cu Quantum Dots Enable Dendrite-Free Potassium Metal Anodes

Employing Al foil current collector at the potassium anode side is an ideal choice to entail low-cost and high-energy potassium metal battery (PMB). Nevertheless, the poor affinity between potassium and planar Al can cause uneven K plating/stripping and hence undermined anode performance, which remains a significant challenge to be addressed. Herein, we propose a nitrogen-doped carbon@graphdiyne (NC@GDY) modified Al current collector affording potassiophilic properties that simultaneously suppresses the dendrite growth and prolongs the lifespan of K anodes. The thin and light modification layer (7 μm thick, with a mass loading of 500 μg cm-2 ) is fabricated by directly growing GDY nanosheets interspersed by Cu quantum dots on NC polyhedron templates. As a result, symmetric cell tests reveal that the K@NC@GDY-Al electrode exhibits an unprecedented cycle life of over 2400 h at a 40% depth of discharge. Even at an 80% depth of discharge, the cell can still sustain for 850 h. When paired with a potassium Prussian blue cathode, thus-assembled full cell demonstrates comparable capacity and rate performance with the state-of-the-art PMBs.