Chromium Oxide\nNanoparticles Anchored in Hydrogel-Derived\nThree-Dimensional N‑Doped Porous Carbon Anode Materials as\nLithium-Ion Batteries

Transition metal oxides (TMOs) have been identified as\nthe most\npromising anode materials for lithium-ion batteries (LIBs). However,\nthese materials tend to undergo volumetric expansion during battery\noperation, which disrupts their internal structure and ultimately\nleads to a degradation of battery performance. Cr<sub>2</sub>O<sub>3</sub>/N-doped porous carbon (Cr<sub>2</sub>O<sub>3</sub>@NC) composites\nwere successfully synthesized through high-temperature calcination\nusing Cr<sub>2</sub>O<sub>3</sub>-containing hydrogels as precursors.\nThe results show that the carbon material not only improves the electron\ntransfer ability of Cr<sub>2</sub>O<sub>3</sub> but also effectively\nprevents its agglomeration. The Cr<sub>2</sub>O<sub>3</sub>@CN composite\nas a novel anode material for LIBs exhibits a reversible capacity\nof 936 mAh g<sup>–1</sup> after 200 cycles at a current density\nof 1 A g<sup>–1</sup>, showcasing excellent cycling and structural\nstability during cycling. Scanning electron microscopy analysis reveals\nthat the Cr<sub>2</sub>O<sub>3</sub>@NC composite remains structurally\nintact throughout cycling. The innovative approach proposed in this\nstudy provides a new direction for the advancement of electrode materials\nfor energy storage technologies.