Solar water splitting with nanostructured hematite: The role of annealing-temperature

In this study, we apply a two-step annealing method to fine-tune the microstructure of hematite. The influence of annealing temperature on the corresponding photoelectrochemical performance is explored. Multiple surface analyses revealed that the short time high temperature annealing treatment based on long time stabilized treatment have properly activated the PEC performance of hematite. The sample of Fe2O3-800 showed the best photo activity enhancement and the corresponding photocurrent density was about tenfold higher than that of Fe2O3-550 sample. The achieved improvement was related with crystallite size and the diffusion and incorporation of Sn atoms. Increasing with the annealing treatment temperature, the sample showed gradually reduced charge transport resistance and suppressed charge carrier recombination process.131