Polyol-solid surface/interface transesterification strategy to construct precise anatase/rutile TiO₂ hetero-phase junctions towards enhanced photocatalytic performance

Heterophase anatase/rutile junctions (A/R-HPJs) in TiO2 hold significant promise for photocatalysis, yet precise control over phase composition remains elusive. Here, we develop a novel polyol-solid surface/interface transesterification strategy to synthesize TiO2 A/R-HPJs with tunable mass ratios for photocatalytic seawater splitting and dye degradation. Mechanistic studies reveal that glucose-Ti complexes (GTCs) govern rutile formation, enabling a linear correlation between A/R mass ratios and GTC/Ti molar ratios. Increasing glucose particle surface area via grinding enhances rutile content, evidenced by amplified slope values in this linear relationship. This approach for constructing precise A/R TiO2 HPJs demonstrates generalizability across diverse polyols, non-solubilizing solvents, and titanium precursors. Phase-dependent carrier separation efficacy is highlighted, with optimized GT15 (optimal A/R ratio) exhibiting exceptional photocatalytic H2 evolution and pollutant degradation. Our work establishes a surface/interface engineering paradigm for precise heterophase control in metal oxides, addressing a critical gap in designing functional HPJs for energy and environmental applications.