Synthesis and performance of chitosan-coated flower-like CuBi2O4/BiOBr photoanode in photocatalytic fuel cell

Photocatalytic fuel cell (PFC) is a new device that can efficiently degrade organic pollutants and recover their energy. This paper used solvothermal method to prepare a flower-like copper bismuth oxide/bismuth oxy bromide/Chitosan/Titanium (CuBi 2 O 4 /BiOBr/CS/Ti) photoanode. It was then assembled with a Cu cathode to produce a PFC for reducing rhodamine B (RhB) and generating power. Different analytical methods were utilized to analyze the photoanode's chemical composition, crystal structure, and electrochemical properties. CuBi 2 O 4 /BiOBr/CS/Ti had higher photocatalytic activity than single and binary composite photoanodes, which had good stability. The RhB degradation rate, maximum power density ( P max ), maximum photocurrent density ( J sc ) and the fill factor ( FF ) of the PFC were 90.98 %, 30.80 μW·cm −2 , 0.283 mA·cm −2 and 0.22, respectively. The results of transient photocurrent (i-t), electrochemical impedance spectra (EIS) and Mott-Schottky (M-S) spectra, and free-radical capture experiments indicated that the enhancement of the photocatalytic performance of the CuBi 2 O 4 /BiOBr/CS/Ti photoanode was due to the formation of the Z -scheme heterojunction between CuBi 2 O 4 and BiOBr and the electron mobility of CS. This achieved the rapid separation and transfer of electron (e − )-hole (h + ) pairs and maintained the strong oxidation of holes in the valence band (VB) of BiOBr and the strong reduction of electrons in the conduction band (CB) of CuBi 2 O 4 . This research introduces a novel approach to design and establish excellent performance photoanode of PFC system.