Li reaction behavior of GaP nanoparticles prepared by a sodium naphthalenide reduction method

Abstract

Li reaction phenomena of GaP nanoparticles (<30 nm) prepared by a sodium naphthalenide reduction method at 390°C in an autoclave were investigated using electrochemical, in (ex) situ X-ray diffraction (XRD), and X-ray absorption spectra (XAS) measurements between 1.5 and 0 V. During the first discharge reactions, lithium intercalated Li 2GaP and irreversible Li nP 7 phases were formed. Li 2GaP was only stable above 0.36 V after which it decomposed to Li xGa and electrochemically inactive Li nP phases. Overall, the reversible capacity contribution (∼800 mAh/g) was from the reversible phase transformation between the Li xGa and Ga phases.