Targeted EtchingStrategy to Expand Low-Voltage Plateauof Pitch-Based Hard Carbon for Sodium Storage

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:Provides a novel etching-carbonization protocol to boost closed-pore capacity in hard carbon anodes for SIBs.

🏢実務担当者:Offers a scalable pathway to improve pitch-derived carbon anodes for next-generation batteries.

🏛政策担当者:Highlights progress in SIB technology supporting energy storage diversification and resource independence.

To address the lack of voltage plateau, low plateau capacity, and poor cycling stability in pitch-derived carbon anodes, a hard carbon material was synthesized via CO₂-assisted etching combined with high-temperature carbonization of preoxidized pitch. Preoxidation introduces C–O/CO groups into pitch, suppressing its pyrolysis melting and enabling uniform nanopore formation. Subsequent CO₂ etching at 800 °C selectively expands micropores while reducing oxygen content (from 14.94% to 8.05%), and final carbonization further converts open pores into closed pores. These integrated strategies endow the material with outstanding sodium storage performance, achieving an initial Coulombic efficiency of 90%, a reversible capacity of 347.6 mAh g^–1 (including a plateau capacity of 249.4 mAh g^–1), and 87.3% capacity retention after 200 cycles at 100 mA g^–1. The enhanced stability originates from the formation of a thin solid electrolyte interphase with organic–inorganic gradient structure and a triphasic mechanism involving adsorption (>0.10 V), intercalation (0.01–0.10 V), and pore filling (<0.01 V), highlighting the critical role of closed-pore engineering of pitch-derived hard carbon for high-performance sodium-ion batteries (SIBs).

• openalex https://figshare.com/articles/journal_contribution/Targeted_Etching_Strategy_to_Expand_Low-Voltage_Plateau_of_Pitch-Based_Hard_Carbon_for_Sodium_Storage/32754229first seen 2026-06-26 05:02:04