A vanadium-based metal–organic phosphate framework material K2[(VO)2(HPO4)2(C2O4)] as a cathode for potassium-ion batteries

Abstract

Herein, we report a layered material K₂[(VO)₂(HPO₄)₂(C₂O₄)] with a large interplanar lattice spacing. Highly reversible K⁺ extraction and insertion in the layers are achieved, with a good cycling stability of up to 200 cycles (83% of retention). And the structural evolution of this material during the electrochemical processes is explored.