Understanding the link between solid/liquid interfaces and photoelectrochemical activity in novel thin-film photoanodes of preferentially oriented high-index rutile TiO2 facets – A work inspired by Michel Che’s research on surface chemistry

•High-index facet Rutile TiO2 thin films were hydrothermally grown on a FTO substrate.•Low-index facet films can be grown the same way, allowing for precise comparisons.•Interfaces of twin boundary defects enhanced water splitting.•This work was inspired by Michel Che’s research legacy of catalysis on interfaces.