The electrophoretic loading of porous perovskite-lanthanum cobaltite (LaCoO3) on bismuth doped g-C3N4 (Bi@g-C3N4) as a novel photoanode was designed for the efficient photoelectrocatalytic water splitting. Before loading cocatalyst, the photoelectrocatalytic oxygen evolution of g-C3N4 was investigated with various amounts of Bi. The photoconversion efficiency enhanced more than 3.7 times for 3.6% Bi doped compared with that of the pristine g-C3N4. The Mott-Schottky plots showed the amount of band bending for Bi@g-C3N4 is more than that of g-C3N4 resulting in better electron transfer at the photoelectrode/electrolyte interface. By loading LaCoO3 on Bi@g-C3N4 photoanode, the photoconversion efficiency of 2.3% at 0.28 V (vs. RHE) was obtained under visible light which is more than that of Bi@g-C3N4 (0.92% at 0.48 V vs. RHE) alone. The high photocurrent density of 0.40 mA cm -2 was observed for Bi@g-C3N4/LaCoO3 photoanode as compared with Bi@g-C3N4 (0.17 mA cm -2) at the redox potential of O2/H2O. Also, Bi@g-C3N4/LaCoO3 photoanode represents a smaller arc radius in electrochemical impedance spectroscopy Nyquist plot compared with those of g-C3N4 and Bi@g-C3N4.

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