Design of TiO₂@Carbon@Prussian Blue Core–Shell Nanorod Arrays for Enhanced Photoelectrochemical Performance

The thoughtful design of effective photoanodes has drawn significant attention. Here, a Z-scheme core–shell TiO2@carbon@prussian blue (TiO2@C@PB) is designed for photoelectrochemical water splitting. TiO2@C@PB composite film has a larger absorption range, and the band gap is decreased from 3.10 to 2.65 eV. Under illumination conditions, the TiO2@C@PB composite photoanode achieves a photocurrent density of 2.78 mA/cm2 at 1.23 V vs RHE, nearly 2.5 times higher than that of pure TiO2. The enhancement is ascribed to the suppressed recombination of photogenerated charges facilitated by the Z-scheme heterojunction and the excellent conductivity of carbon. This study offers an effective approach for developing highly efficient photoelectrochemical water-splitting photoanodes