Polythiourea-Decorated CuO Nanorod Films for Efficient Nitrophenol Hydrogenation with Reconstruction

The development of high-performance, noble-metal-free catalytic films for wastewater remediation is fundamentally constrained by weak interfacial affinity, slow mass transfer kinetics, and inadequate structural stability under harsh reducing conditions. In this study, we present a multiscale interfacial engineering strategy to successfully fabricate catalytic films based on one-dimensional (1D) CuO nanorods decorated with an ultrathin polythiourea (PTU) layer. Through sodium citrate-assisted anisotropic growth, a morphological transition of CuO from 2D nanosheets to 1D nanorods is precisely achieved. The results demonstrate that, owing to their high aspect ratio, the 1D nanorods can form an effective mechanical interlocking network with porous substrates, thereby overcoming the critical adhesion bottleneck associated with catalyst detachment in liquid-phase environments. The film modified with 10 mL of PTU exhibits an optimal reaction time of 18 min for the catalytic reduction of 4-nitrophenol. Two-dimensional correlation spectroscopy is employed to unambiguously elucidate the catalytic kinetic pathway at the molecular sequential level. The hybrid film maintains a conversion rate exceeding 95% over 14 consecutive batch cyclic tests. Postreaction characterization reveals a unique “adaptive in situ reconstruction” mechanism: although the 1D nanorods evolve into a 3D porous nanoparticle network, the robust PTU polymer chains act as flexible binders that firmly anchor the reconstructed active species, ensuring exceptional long-term durability. This study not only provides a scalable paradigm for designing ultrastable catalytic films but also establishes a transformative spectroscopic methodology for probing interfacial dynamic kinetics at the molecular level.