Designing efficient transfer channels in the photoanodes of photocatalytic fuel cells is an innovative approach to achieving directional charge migration and shortening transmission pathways, enhancing the oxidation reaction, thereby amplifying electrical signals to improve the sensitivity and expand the detection range for target analytes. However, the catalytic performance of g-C₃N₄ for oxygen evolution reaction remains limited due to insufficient sunlight absorption and slow charge migration.
Herein, this study employs the coupling of the covalent bonds as transfer channels by anchoring atomically dispersed W species to accelerate electron migration in g-C₃N₄, synergistically improving the water oxidation activity, thus amplifying the open circuit potential in the photocatalytic fuel cell system. The self-powered sensor demonstrated a broad detection range spanning five orders of magnitude (2.0 × 10^–2 ~ 9.2 × 10² nmol∙L^–1), a low limit of detection (7.0 pmol∙L^–1), high selectivity against common interferents. Furthermore, the platform allowed for self-powered and portable determination of copper ions using a multimeter as a signal output device, achieving a detection range of 0.25 ~ 1.3 × 10² nmol∙L^-1 and a limit of 84 pmol∙L^–1.

DOI:10.1016/j.actphy.2025.100144