Self-N-doped hierarchical porous carbon electrodes derived from shrimp shells for high-performance membrane capacitive deionization
Journal
Desalination
Journal Volume
618
Start Page
119508
ISSN
00119164
Date Issued
2026-01-15
Author(s)
Abstract
Biochar-derived carbon materials have attracted considerable attention as sustainable and cost-effective electrode candidates for membrane capacitive deionization (MCDI). In this study, a self‑nitrogen-doped hierarchical porous carbon electrode was successfully synthesized from nitrogen-rich shrimp shell, featuring optimal nitrogen functionalities (pyridinic-N and quaternary-N) and a hierarchical porous structure. The distribution of nitrogen species was in-situ tuned by optimizing the activation temperature, without requiring any additional nitrogen precursors. A higher pyridinic-N content enhanced the pseudocapacitance, while an increased proportion of quaternary-N improved the electrical conductivity, thereby boosting the overall electrochemical performance. Meanwhile, the tailored hierarchical porous structure facilitated both ion transport and ion storage. The improved desalination performance in MCDI was primarily attributed to the synergistic effects of self‑nitrogen doping and hierarchical porosity. Among all samples, the electrode activated at 800 °C (SSHPC800) exhibited the highest mean desalination capacity of 10.8 mg/g and demonstrated excellent stability during repeated electrosorption/desorption cycles. This work demonstrates that in-situ nitrogen doping from shrimp shell not only eliminates the need for additional nitrogen sources but also tailors the distribution of active nitrogen species, thereby enhancing both the capacitive properties and electrosorption performance of the carbon electrodes. This strategy offers a sustainable pathway for developing high-performance MCDI electrodes for advanced electrochemical desalination.
Subjects
Electrosorption
Hierarchical porous carbon
Self-N-doped biochar
Shrimp shell
SDGs
Publisher
Elsevier B.V.
Type
journal article