Nanotubular Curvature-Induced Internal Electrostatic Field Realizing Chemoselective Hydrogenation

Chemoselective hydrogenation of nitroarenes to corresponding aniline derivatives is crucial for fine chemical synthesis, yet an inherent trade-off between activity and selectivity remains a critical challenge. Here, we successfully developed Pt catalysts confined in TiO₂nanotubes (TNTs) to address this challenge. Comprehensive characterizations and theoretical calculations reveal that the curvature strain of TNTs induces electron migration from the concave interior surface to the convex exterior surface, thereby self-generating an internal electrostatic field within the lumen, without the utilization of additional electric devices or considerable energy consumption. This electrostatic field forces the directional radial arrangement of high-polar molecules of 3-nitrostyrene (3-NS) inside TNTs via field–dipole interactions; that is, the strongly electronegative −NO₂group points perpendicularly toward the interior surface. The spontaneous specific adsorption configuration of 3-NS is independent of the structures of Pt sites, allowing them to maintain their hydrogenation ability without sacrificing either quantity or intrinsic activity. Consequently, the as-developed 0.5Pt/TNTs-In catalyst achieves an unprecedented turnover frequency (∼30,000 h^–1), about 3-fold higher than the previous maximum value of state-of-the-art Pt-based catalysts, along with ultrahigh specific activity (108 mmol g_cat^–1h^–1), while achieving 97% chemoselectivity at a conversion of 95% toward 3-vinylaniline under ambient reaction conditions. Our strategy applies broadly to polar molecules, pioneering a paradigm in chemoselective hydrogenation and providing an ideal approach for developing scalable and sustainable catalyst systems.