The influence of Ti and Si doping on the structure, morphology and photo-response properties of α-Fe2O3 for efficient water splitting: experiment and first-principle calculations

Ti- and Si- doping effects on morphology, structure, optical and photo-response of α-Fe2O3
nanoscale coatings from atmospheric-pressure chemical vapour deposition (APCVD) have
been studied. Si- and Ti-doping led to larger clusters with finer grains and smaller clusters
with larger grains, respectively. Photocurrent performance was increased remarkably by
doping, especially Si. Excellent agreement was found for band gaps and optical properties
compared to hybrid-Density Functional Theory. Substitutional replacement of Fe by Si
shrinks the volume more than Ti-doping; it is conjectured that this affects hopping probability
of localised charge-carriers more and leads to enhanced photocurrent activity for Si-doping,
supported by experiment.