Cu3P nanoparticles confined in nitrogen/phosphorus dual-doped porous carbon nanosheets for efficient potassium storage

Abstract Immobilizing primary electroactive nanomaterials in porous carbon matrix is an effective approach for boosting the electrochemical performance of potassium-ion batteries (PIBs) because of the synergy among functional components. Herein, an integrated hybrid architecture composed of ultrathin Cu3P nanoparticles (~20 nm) confined in porous carbon nanosheets (Cu3P⊂NPCSs) as a new anode material for PIBs is synthesized through a rational self-designed self-templating strategy. Benefiting from the unique structural advantages including more active heterointerfacial sites, intimate and stable electrical contact, effectively relieved volume change, and rapid K+ ion migration, the Cu3P⊂NPCSs indicate excellent potassium-storage performance involving high reversible capacity, exceptional rate capability, and cycling stability. Moreover, the strong adsorption of K+ ions and fast potassium-ion reaction kinetics in Cu3P⊂NPCSs is verified by the theoretical calculation investigation. Noted, the intercalation mechanism of Cu3P to store potassium ions is, for the first time, clearly confirmed during the electrochemical process by a series of advanced characterization techniques.