Temperature‐Tuned Barley‐Husk Hard Carbon for Sodium‐Ion Batteries: Linking Porosity, Turbostratic Order, and Na Storage Kinetics
Year: 2026
Type: article
Abstract: Hard carbon‐based anodes were prepared from barley husk, an abundant agricultural residue containing carbonaceous matter and naturally occurring silica, and assessed for Na‐ion storage as a function of carbonization temperature. A broad temperature series (450–1150 °C) was used to establish the evolution of bonding‐scale order, turbostratic stacking, and pore architecture, while Na half‐cell testing was performed for representative anodes carbonized at 550, 750, 950, and 1150 °C using 1 M NaPF 6 in diglyme. Characterization confirmed progressive structural consolidation with increasing temperature, accompanied by marked changes in accessible porosity. Electrochemical behaviour showed a non‐monotonic dependence on temperature, with an intermediate carbonization temperature providing the most favourable balance between reversible capacity and interfacial/transport limitations. In particular, BH‐T750 delivered the highest sustained capacity (≈230 mAh g −1 at C/5) with stable cycling and strong rate response compared with lower‐ and higher‐temperature carbons. Differential capacity and impedance analyses support a mechanism combining intermediate‐potential adsorption‐type storage with low‐potential storage in confined domains, with the relative contribution governed by the interplay between turbostratic ordering and pore accessibility. These results identify a practical processing window for sustainable Na‐ion anodes derived from barley husk.
DOI: 10.1002/aesr.70284
Authors: Alireza Fereydooni, Chenghao Yue, Yimin Chao
Institutions: University of East Anglia, Tyndall Centre
Language: English
Subfield: Electrical and Electronic Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $3,910
Funder: Leverhulme Trust
OpenAlex ID: W7163892367