A combinatorial guide to phase formation and surface passivation of tungsten titanium oxide prepared by thermal oxidation

摘要: TiO$_2$ and WO$_3$ are two of the most important earth-abundant electronic materials with applications in countless industries. Recently alloys have been investigated leading to improvements key performance indicators for a variety ranging from photo-electrochemical water splitting electrochromic smart windows. These positive reports complexity ternary W-Ti-O phase diagram motivate comprehensive experimental screening this space. Using combinatorial thermal oxidation solid solution W$_{1-x}$Ti$_{x}$ precursors combined bulk surface analysis mapping we investigate oxide formation passivation tungsten titanium entire compositional range pure TiO$_2$. The system shows remarkable structural transition monoclinic over cubic tetragonal symmetry increasing Ti concentration. In addition, strong enrichment is observed precursor Ti-concentrations excess 55 at.%, resulting protective rutile-structured layer. Despite transitions, optical properties remain largely unaltered demonstrating an independent control multiple functional W$_{1-x}$Ti$_{x}$O$_{n}$. results study provide valuable guidelines future development W$_{1-x}$Ti$_{x}$O$_{n}$ energy applications, but also novel engineering approaches functionalization additive manufacturing Ti-based alloys.