Publication: Seawater nanoarchitectonics for an eco-friendly dual-function activator-catalyst producing graphene-decorated activated biochar for applications in electrochemical energy storage
2
0
Issued Date
2025-05-01
Resource Type
ISSN
00139351
eISSN
10960953
Scopus ID
2-s2.0-85218442163
Pubmed ID
39986427
Journal Title
Environmental Research
Volume
272
Rights Holder(s)
SCOPUS
Bibliographic Citation
Environmental Research Vol.272 (2025)
Suggested Citation
Phakkhawan A., Kosolwattana S., Sakulsombat M., Pimanpang S., Klangtakai P., Amornkitbamrung V. Seawater nanoarchitectonics for an eco-friendly dual-function activator-catalyst producing graphene-decorated activated biochar for applications in electrochemical energy storage. Environmental Research Vol.272 (2025). doi:10.1016/j.envres.2025.121176 Retrieved from: https://hdl.handle.net/20.500.14740/20324
Author's Affiliation
Corresponding Author(s)
Other Contributor(s)
Abstract
Activated biochar (AB) powder derived from sawdust was prepared using 0.6 M NaCl as a dual-function activator-catalyst at temperatures ranging from 500 to 1000 °C. The AB synthesized at 900 °C (NaCl-AB-900) shows the highest specific surface area (880.05 m2 g−1). Seawater was then used as the dual activator-catalyst to explore sustainable alternatives, producing Seawater-AB-900 powder with a specific surface area similar to the NaCl-AB-900 powder (890.34 m2 g−1). In contrast, the non-activated biochar (Non-AB-900, 782.45 m2 g−1) has a smaller specific surface area than both AB powders. SEM and TEM analyses reveal that both AB powders have graphene decoration and porosity, whereas the Non-AB-900 powder only exhibits porosity. Electrodes made from NaCl-AB-900 and Seawater-AB-900 powders demonstrate higher specific capacitances (81.42 and 84.45 F g−1) compared to Non-AB-900 (64.39 F g−1) at 0.3 A g−1 in a three-electrode system using 6 M KOH. They also exhibit better rate capability (76.54% and 70.44%) than Non-AB-900 (65.24%). In a two-electrode mode, NaCl-AB-900 and Seawater-AB-900 supercapacitors outperform Non-AB-900 in capacitance (51.76 F g−1, 50.68 F g−1 vs. 25.96 F g−1 at 0.3 A g−1) and rate capability (64.50%, 65.20% vs. 27.59% at 10 A g−1). In a Zn-ion battery system, NaCl-AB-900 (137.07 mAh g−1) and Seawater-AB-900 (142.29 mAh g−1) deliver higher specific capacities than Non-AB-900 (69.03 mAh g−1) at 0.3 A g−1. Both AB electrodes show excellent cycle stability, with over 70% retention after 40000 supercapacitor cycles and 90% after 7000 battery cycles. The Seawater-AB-900-powered supercapacitors and batteries successfully lit an LED for over 2 min.