Plasma-implanted Ti-doped hematite photoanodes with enhanced photoelectrochemical water oxidation performance

Hematite (α-Fe2O3) is recognized as a promising photoelectrode material for photoelectrochemical (PEC) water splitting, result of its abundance, non-toxicity, suitable bandgap, and photochemical stability. Nevertheless, the undesirable physical photophysical behaviors, such poor conductivity, short diffusion length, rapid charge-carrier recombination, seriously restrict PEC splitting efficiency hematite semiconductors. Herein, we fabricate nanoporous titanium (Ti)-doped α-Fe2O3 thin films by facile hydrothermal reaction, subsequently utilizing energetic plasma ion implantation with post-annealing process to significantly enhance oxidation performance hematite. On basis materials characterization electrochemical analysis, optimized Ti-doped Fe2O3, i.e., Ti-4-Fe2O3, exhibits improved photocurrents 0.55 1.07 mA cm−2 at 1.23 1.5 V versus RHE respectively under illumination 100 mW/cm2 AM G spectrum, showing approximately 1.6-fold increases compared pristine Fe2O3. We attribute this increase charge carrier transport induced Ti doping that reduces recombination light-driven carriers. The work plasma-assisted technique provides new insights into surface engineering photo-responsive semiconductors development emerging hydrogen technologies.