2D few-layer iron phosphosulfide: a self-buffer heterophase structure induced by irreversible breakage of P–S bonds for high-performance lithium/sodium storage

摘要: To pursue an anode candidate with a high capacity and favorable potential is urgent for prospective energy storage system. In this work, earth-abundant ternary metal phosphosulfide, here FePS3, which expected to combine the merits of sulfide phosphorus, explored lithium/sodium storage. order facilitate charge transfer relieve volume stress on electrode, oriented nanoengineering few-layer FePS3 nanosheets uniformly anchored into porous graphene network was carried out. Consequently, excellent lithium capacities 842.7 570 mA h g−1 were delivered after 120 cycles at 0.1 A 1000 1 g−1, respectively. Moreover, electrode showed cycle stability sodium storage, delivering reversible 256.4 300 0.05 g−1. The electrochemical performance competitive compared state-of-the-art binary sulfides phosphides. Besides nanoengineering, more interestingly, intrinsic phase evolution mechanism plays substantial role in reaction. Through characterization by ex situ XRD, FT-IR, HRTEM, EIS studies, single-phase irreversibly transformed nano-sized FexSy phosphorus heterophase structure accompanying breakage P–S bonds first cycle. view different lithiation potential, formed mixed phases can serve as inert buffer matrix each other, alleviating aggregation pulverization electrodes caused change. This study proposes synergistic pathway, combines advantages process achieve high-performance phosphosulfide.