Biomaterials possess abundant micro and macrospores in their microstructures, which can be functionalized as higher ion-transport channels. Herein we report calcined crab shell (CCS) forming nanocomposites with La0.6Sr0.4CO0.2Fe0.8O3 (LSCF) perovskite as functional electrolytes for low temperature solid oxide fuel cells (LTSOFCs). The single CCS electrolyte fuel cell achieved open circuit voltage (OCV) at 0.9 V and a peak power density of 70 mW cm(-2) at 550 degrees C; while the highest OCV of 1.21 V and a maximum power density of 440 mW cm(-2) were achieved for the CCS-LSCF (40 wt. % LSCF) electrolyte fuel cell. The results are attributed to the ion channel construction and interface effect built in the CCS-LSCF composite. This work may provide a new strategy to develop novel biomaterial-based materials for LTSOFCs. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.